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Inflammatory Bowel Disease (IBD)

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IBD is an inflammatory condition of the stomach, small intestines, or large intestines (the gastrointestinal (GI) tract).  It is sometimes called Idiopathic IDB. The Idiopathic part means that the cause of the condition is unknown.

IBD tends to be chronic in nature.  It is one of the most common conditions of the gastrointestinal tract diagnosed in pets, especially in cats. Despite its prevalence, it is one of the least understood conditions, especially regarding cause. Some pets respond well to treatment, others do not.

Some cases of IBD involve the liver and pancreas. In this case there are 3 diseases occurring, and we refer to it as Triaditis. This is more difficult to treat than IBD alone.

The usual symptoms of IBD are poor appetite, vomiting, diarrhea, and weight loss.  Cats tend more  towards vomiting, dogs tend towards diarrhea. These symptoms appear in many other diseases, so you cannot assume your pet has IBD from symptoms alone. To learn the process of how we make a diagnosis of a disease when the symptoms are the same as so many other diseases, we have a methodical and detailed approach. It is called the Diagnostic Process.

We discuss the importance of worms (internal parasites) many times in this page in regards to IBD. With the modern medications we have, including flea products that contain medication to kill worms, it behooves you to treat your pets for worms monthly. Not only might it help prevent IBD from appearing at some time in your pet’s life, it will protect you and your children. Our Internal Parasites page has the scoop on all of this.

In spite of its prevalence, many pets are diagnosed with Idiopathic IBD when they do not have it. To standardize what IBD is, the World Small Animal Veterinary Association has listed the following criteria to help make this diagnosis:

The GI symptoms must be present for at least three weeks

Diet change, worming, and medication do not give a significant reduction in symptoms

No other explanations can be found for the symptoms

Biopsies of the intestines show significant inflammation of the interior lining

The resolution of symptoms when put on mediations that modulate the immune system (immunosuppressive).

This criteria means that a pet that responds to just a diet change technically has a Food Responsive Enteropathy. If a pet responds just to antibiotics then it technically has an Antibiotic Responsive Enteropathy.

Graphic photos of surgeries are on this page

Anatomy and Physiology of the Gastrointestinal (GI) Tract

When your pet eats, food from the stomach passes into the small intestine, which is composed of three different sections called the duodenum, jejunum, and ileum.

The majority of nutrient (proteins, carbohydrates, fats) digestion occurs within the small intestines.  The inner lining of the intestines is called the mucosa, and that’s where all the action occurs when it comes to absorbing nutrients. The mucosa has a large surface area because there are microscopic folds called villa.

Ilium-NormalMucosa

This is the lining of the small intestines. The villa are microscopic, so you cannot see them without a microscope.

There are many different types of specialized cells in the lining of the mucosa. Some of these cells specialize in aiding digestion, some are for absorption of these nutrients into the bloodstream, and some are part of the immunes system and defend the body from foreign invaders.

These immune system cells are important for protection due to the constant exposure the GI tract has to outside invaders in the form of oral ingestion of food and its many contaminants. It is these cells that can overreact and cause IBD symptoms.

Surgery-SmallIntestines

These are the small intestines during a routine abdominal surgery. Notice the extensive blood supply, necessary to get those nutrients from the lining of the intestines into the bloodstream, and then off to every cell in the body- amazing!

Ilium-Ingesta

This is what the ingesta looks like as it passes through the small intestines

The pancreas secretes digestive enzymes into the small intestines as the food passes through the duodenum. These enzymes are crucial for digestion of fats, carbohydrates, and proteins. As the food continues down the small intestines the enzymes from the pancreas continue their breakdown of nutrients, which are then absorbed by the mucosa of the jejunum and ileum and make it into the bloodstream.

Pancreas-labeled

This is the pancreas, a small but mighty organ. Our surgeon is holding the duodenum (D), with the pancreas in the center (D).

Pancreas-Normal

Close up view of the architecture on the outside of the pancreas

The gall bladder secretes bile into the duodenum to help in digesting fats. When the liver is a part of IBD the bile can build up in the liver and cause a problem. This is a part of the Triaditis that complicates IBD.

The large intestine is composed of the cecum (our appendix), colon, rectum, and anus. Water, electrolytes (sodium and potassium), sugars, and vitamins are the main nutrients absorbed by the large intestine. Some vitamins are produced in the large intestine also. Nutrients that were not broken down or absorbed well enough within the small intestine are further digested in the large intestine due to microbial fermentation. The large numbers of these good bacteria that are present in the intestines are crucial to normal health.

The human cecum (appendix) has atrophied to the point that it is no longer needed. Our diet does not have the fiber of our ancestors, so this organ is not needed for normal digestion, which is why it can be removed if appendicitis occurs. As a fun anatomical comparison, the cecum of a rabbit is enormous in relation to the rest of its body. That is because it is a hind-gut fermenter, and contains large numbers of bacteria to help digest food that is high in fiber. Our rabbit GI stasis page has radiographs of the cecum along with actual pictures to give you an idea of just how large it is.

Pathophysiology

Allergens cause inflammation of the mucosa, leading to the symptoms associated with IBD. The allergens that cause this inflammation can be anything, with food (especially protein) as the main culprit.  Bacteria and parasites are also allergens that cause inflammation of the mucosa. It is the immune system that over reacts to these antigens that causes the symptoms of IBD. This immune system over reaction is why pets that truly have IBD need medication to suppress the immune system, in addition to dietary changes and antibiotics.

Intesinte-normal lumen

The size of the lumen thorough with the food passes and intestinal wall thickness of a normal small intestine

ThickenedSmallIntestine

You can easily see the smaller lumen and thickened intestinal wall in this pet with IBD

Inflammation of the pancreas is known as pancreatitis. In pancreatitis, the digestive enzymes that would normally be secreted into the duodenum to digest food are now leaking out of the pancreas into the abdomen, causing tremendous inflammation and pain to surrounding organs. Pancreatitis is a serious disease, and usually requires hospitalization, intravenous fluids, and medication. It can be hard to diagnose in cats because they usually become quiet and sit as if content, when in reality they are in pain. A clue is the fact that are not eating well.

Inflammation of the liver in some cases may be associated with IBD, permitting an infection to creep up the bile duct and into the liver. There are many different sources to this infection, ascending from the GI tract or urinary tract.

The pancreas, liver, and intestines are closely associated, and when one has a problem it causes inflammation in one of the other ones. When all three have a problem it is called Triaditis. As you can see, it all gets quite complicated.

Cause

IBD is one of those conditions where the exact cause might never be identified. The most common causes are dietary allergies, infections, and environmental stress. Stress can happen in multiple pet households, during holidays, and in extreme weather.

Dietary allergies are involved with sensitivity to protein in the diet. Sometimes, an inability to absorb nutrients, called a malabsorption syndrome, is involved. Some pets generate an excessive amount of a specific white blood cell called an eosinophil (eosinophil gastroenteritis) in the lining of the GI tract.

Other dietary causes might include artificial coloring, preservatives, and food additives. Differentiation between the above-mentioned causes is difficult, especially since many IBD cases are associated with several concurrent factors.

It is suspected that puppies with a large amount of internal parasites (worms) are setting the stage for IBD later in life. This is another good reason to have your pet checked for internal parasites at least yearly, and wormed frequently when young.

Pancreatitis is highly associated with pets that are overweight, particularly spayed female dogs. Fatty meals are important components of the clinical history for cases involving pancreatitis. As a result, we tend to see this cause of pancreatitis around the holidays when people are celebrating with turkey (and gravy) and other similar foods that their pets’ eat also.

Inflammation of the pancreas can spread to the liver  due to its proximity.  This can inflame the gall bladder, causing bile to backup into the liver. This can lead to Triaditis mentioned earlier.

Inflammation of the liver and biliary system, known as cholangiohepatitis, is most commonly associated with a bacterial infection.  In cases of Triaditis, it is unknown as to whether the liver is the first organ affected, resulting in secondary inflammation of the pancreas and gastrointestinal tract, or if it is the other way around.  It has been hypothesized that bacterial infections may be the initiating cause of cholangiohepatitis, with IBD and pancreatitis following thereafter.

Dietary Induced

Proteins and grains in the food contribute to dietary intolerance. Intolerance occurs when there is an abrupt change in the diet, resulting in an inability for the gastrointestinal tract mucosa and associated cells to adapt accordingly.  When this happens foods are often not digested or absorbed properly.

Maldigestion is a separate condition of the gastrointestinal tract that generally occurs secondary to exocrine pancreatic insufficiency. The endocrine pancreas secretes insulin to regulate the blood glucose level. The exocrine pancreas secretes the digestive enzymes needed to digest food in the intestines. If the pancreas is not secreting enzymes into the small intestines as the food passes, the nutrients will not be broken down and absorbed into the bloodstream. This leads to weight loss and diarrhea, even in a pet that is eating.

Malabsorption is secondary to numerous disease processes such as food allergies and/or intolerance, protein losing diseases of the gastrointestinal mucosal layer, intestinal parasites, antibiotic responsive disease, cancer, IBD, and immune-mediated disease. The exocrine pancreas is secreting the proper digestive enzymes in this cause. It is an inflammation of the inner lining of the intestines (the mucosa) that prevents absorption of the nutrients into the bloodstream.

Intestinal parasites (worms)

There are numerous intestinal parasites known to cause the same symptoms as IBD. They include roundworms, hookworms, whipworms (dogs only), cryptosporidia (protozoa), toxoplasma (protozoa; cats only), coccidia, and giardia.

Some intestinal parasites are known to affect humans as well (zoonotic potential). These include the larvae of roundworms causing organ involvement (visceral larval migrans), or eye involvement (ocular larval migrans), hookworms (skin involvement), giardia (gastrointestinal disorders), coccidia (gastrointestinal disorders especially in immune suppressed individuals), toxoplasma (congenital defects in babies), and cryptosporidia (gastrointestinal disorders).

A fecal examination is often one of the first steps when diagnostics are being evaluated in a pet with a gastrointestinal disease. Our intestinal parasites page has detailed information on these parasites (worms). We sometimes do  a fecal Giardia test since this parasite can be hard to detect.

Cancer – Lymphosarcoma (Lymphoma)

In cats, lymphosarcoma is the most common type of cancer known to affect the gastrointestinal tract. This is not easy to diagnose, since the changes present in IBD are very similar to those in Lymphosarcoma when the pathologist analyzes them under the microscope.

Depending on the type of lymphoma (small, medium or large cell lymphoma), tissue samples must be sent in for further diagnostics in order to definitively differentiate between early cancer and IBD. Proper treatment depends upon a proper diagnosis.

VeryThickenedSmallIntestine

These severely thickened intestines are from cancer

We have a page that shows an exploratory surgery on a cat with intestinal cancer.

Bacterial infection

Although there are no definitive infectious agents that consistently result in IBD, some organisms such as Giardia, Salmonella, Clostridium, and Campylobacter could be a cause. Some of the “good” bacteria, those that are necessary for life, can become imbalanced and cause the symptoms seen in IBD.

Medications

Any medication can disrupt the lining of the intestines. The most common one is antibiotics, since they disrupt the normal GI bacteria (referred to sometimes as flora).

Other causes

Toxicities (plants, chemicals), hyperthyroidism, FIP, FeLV, FIV .

Diagnosis

Signalment

Both dogs and cats are commonly affected by IBD, although it is much more of a problem in cats. IBD can occur at most any age due to the numerous causes of the condition; however, it is usually observed in pets over the age of two .

Triaditis is more commonly diagnosed in middle to older aged cats.  If it is associated with a food allergy, they tend to be young adults to middle aged. Males and females get IBD in equal frequencies.

Addison’s disease, which is common in Standard Poodles, can cause symptoms similar to IBD.

History

Sometimes pets are affected by IBD for many years while appearing apparently healthy in all other aspects. Typical symptoms are  lethargy, poor appetite (anorexia), weight loss, diarrhea and vomiting.

Depending on the inciting cause, the clinical signs may occur intermittently over a long period of time (i.e. dietary allergy) or abruptly and progressively (immune-mediated, infectious, dietary allergy, cancer). If Triaditis is present clinical signs may range from lethargy and decreased appetite to severe vomiting, diarrhea, abdominal pain, and icterus (jaundice) due to liver compromise).

OLYMPUS DIGITAL CAMERA

This pet has severe icterus (also known as jaundice)

Cats can have variable symptoms compared to dog. Cats that have pancreatitis might sit quietly and appear to have no problems. In reality, these cats are painful, which is why they sit like this.

Physical Exam

In both dogs and cats, palpation of the abdomen might reveal painful and thickened bowel loops. This is not a consistent sign, and just because bowel loops are thickened, does not mean there is a problem. Pain may also be associated with palpation of the pancreas or liver in cases of Triaditis.

Lymph nodes deep within the abdomen may be enlarged and palpable as well as painful. Excessive intestinal sounds (called borborygmus ) might be heard on auscultation of the abdomen. In more chronic cases, other subtle signs may be present such as a dull hair coat, mild to moderate dehydration, fever, and overall poor body condition. None of these are consistent findings, and cannot be relied upon for a diagnosis of IBD.

XRays-LymphNode

These lymph nodes, call the sub lumbar, are enlarged on this dog. They are the whitish circles within the red circle. They are due to cancer, but they cannot be palpated.

Diagnostic Tests

Complete blood count, biochemistry panel, and urinalysis, are a starting point for diagnosis. Certain blood values might suggest IBD if in combination with clinical signs. Even “normal values” are clinically diagnostic, as they help to rule out another disease that can cause the same symptoms as IBD. A pet with a perfectly normal blood panel can still have IBD.

Some pets will have a chronic anemia (low red blood cells). Sometimes the white blood cells will be elevated, in other cases the protein will be low (hypoproteinemia). There might also be a low cobalamin level.  Cholangiohepatitis (inflammation of the liver) in cats, when Triaditis is present, may be further suspected if bilirubin (hyprebilirubinemia) or liver enzymes are increased. A bile acids test helps assess the liver in these cases.

LiverTests

The blood panel is very thorough and checks many different organs and systems. This is a few of the many tests, the elevated liver tests are circled, and could be a sign of Triaditis in this case.

A resting cortisol test might also be used to eliminate Addison’s (hypoadrenocortocism) disease

Fecal examination is an important and inexpensive test to rule out internal parasites (worms). We sometimes give worm medication (called anthelmintics) to pets with a negative fecal if they have and GI symptoms. This is because a pet can have internal parasites that do not show up on a fecal exam. Our intestinal parasites page has much more information explaining this.

A fecal exam, checking for internal parasites (worms) is important in every pet with any signs of illness. In this exam, we are checking for eggs (ova) of the parasite. A special test for Giardia is also used. 

Bacterial cultures are also utilized in some cases. The bacteria we are checking for include:

Campylobacter

Salmonella

Cryptosporidium

This is what we want to see when we do a urine culture- no bacterial growth in 48 hours

Abdominal radiographs are often normal in cases of IBD, but are a necessary tool to rule out other causes of similar clinical signs. Survey abdominal radiographs are also indicated prior to ultrasound  as well.

Xray-PenniesInRectum

This dog had chronic diarrhea.  Nobody took a radiograph prior to treatment. The cause was not IBD, it was the pennies stuck in the rectum.

IBDRadiograph-thickened intestines

This cat has IBD, as evidenced in this case by the thickened small intestines at the arrow. This can also be a normal finding, and it can also be a sign of intestinal cancer. The more common intestinal cancers are lymphoma, adenocarcinoma, and mast cell tumors.

Prior to the common use of ultrasonography, barium contrast studies were performed in order to reveal disruptions of the mucosal surface along the gastrointestinal tract.  We are looking for filling defects and ulcers of the mucosa and thickening. Barium has lost some of its significance since ultrasonography tends to be much more sensitive. One very nice “side effect” of giving barium to a pet that might be vomiting is its soothing affect on the lining of the intestines (mucosa) to stop the vomiting.

TLI type tests- serum fPLI (pancreatitis), fasting serum TLI (exocrine pancreatic insufficiency), fasting serum cobalamin and folate (small intestinal function and bacterial overgrowth). These are specialized tests and take several days for the results to come back.

Endoscopy is a useful tool since we can observe the lining of the esophagus, stomach, and duodenum for ulcers, lesions, and foreign bodies, that might not show up on a radiograph. Biopsy samples can be taken, although they are not full thickness, and only take the lining of the small intestines. This can lead to an inaccurate diagnosis.

This is a report from a stomach and intestinal biopsy with the endoscope

The most accurate way to diagnose IBD is to perform an exploratory surgery and take full thickness intestinal biopsy samples. If the blood protein level is low (hypoproteinemia) care must be taken because healing can be delayed.

Samples obtained during surgery are analyzed by a pathologist to help confirm a diagnosis of IBD, and also rule in or rule out the possibility of  intestinal cancer. Sometimes  the pathologist cannot tell the difference between IBD and cancer due to the abundance of inflammatory cells. During surgery, samples of other important organs like the liver and lymph nodes can also be obtained. These samples are very informative, and are taken in many cases.

IntestineBiopsy

Surgery has the major advantage of being able to see and palpate the intestines, along with taking a complete (called full thickness) sample of the intestines. This surgeon is using a scalpel blade to take the sample.

These samples are analyzed by a histopathologist. The report might come back with several different terms describing the IBD in specific medical terms, depending on the cell type:

  • Lymphocytic-plasmacyltic (the most common one)- respond best to diet change, antibiotics, and immunosuppressive drugs.
  • Eosinophilic (2nd most common)- respond best to worming medication, diet change, and sometimes immunosuppressive drugs
  •         Neutrophilic- bacteria is a possible cause, so culture and antibiotics, with no immunosuppressive works best
  • Granulomatous- least common, suggests fungal or intra-cellular pathogen

Ultrasonography of the abdomen is an invaluable diagnostic tool. Prior to the advent of ultrasound, exploratory surgery was needed to make an accurate diagnosis, and that was only after biopsy samples were obtained. Ultrasound is dramatically less invasive and expensive compared to surgery, and the results are obtained immediately in many cases. In the case of IBD it can tell us of thickening of the intestines and gives us a suspicion that IBD is indeed present, but it cannot confirm the diagnosis.

Ultrasound is a big aid in the diagnosis of IBD in its ability to to rule out cancer and foreign bodies as a cause of vomiting. It also gives us an accurate way to biopsy internal organs like lymph nodes.

Ultrasound-Machine

Ultrasound is rapid and painless, and the only invasive part is shaving your pet’s abdomen

UltrasoundReport-IBD

This is a typical report of a pet with IBD. Note how detailed it is, and how organ size is measured. 

Ultrasound can be used to measure wall thickness of various segments of the intestinal tract, which yields supportive evidence in the face of clinical signs. However, it cannot be used to differentiate between IBD and other disease processes that result in significant inflammation of the intestinal wall (i.e. lymphoma). This is where surgery has an advantage since full thickness biopsy samples can be taken for analysis

Ultrasound-SmallIntestine

This is what the small intestines look like during ultrasound while they are being measure for size

Ultrasound-Pancreas1

This is what the pancreas looks like, also being measured

Ultrasound-MesLymphNode

All of the abdominal organs are assessed during an ultrasound. This is what an enlarged abdominal lymph node looks like.

Fine needle aspirate samples may be obtained with the guidance of ultrasonography.  Sometimes this test is diagnostic, sometimes it is not. Even though it is not a perfect test, we sometimes recommend it due to the simplicity in obtaining it.

A hypoallergenic diet trial may be issued for cases of highly suspected dietary allergies or intolerance. In such cases, some pets respond when the diet is altered and no further diagnostics are necessary. You must feed this food, and only this food, to see if this works. Sometimes results are immediate, other times it might take several months to know for sure.

This can be a risk if the diet trial is attempted before numerous other disease processes are not first ruled out, especially cancer and internal organ diseases like Feline Hyperthyroidism.  This delay in diagnosis can affect outcome. If clinical signs do not improve or resolve within the first two weeks of the diet trial, then further diagnostic work-up is indicated.

Treatment

Depending on the severity of disease at presentation, treatment must first begin with stabilizing the pet. What we do to stabilize depends on the severity and duration of symptoms.

Symptomatic

Stabilization generally includes intravenous  fluids to correct dehydration, correct electrolyte imbalance, and improve kidney function. If the protein level is low we might use a fluid called Hetastarch.

Pets that are not eating are assist fed a special diet called A/D to maintain appropriate caloric intake and to prevent further disruption of internal organ function and get the GI tract back to normal. Probiotics to help stimulate the normal bacterial flora might be beneficial.

Vomiting pets are continued on fluids to maintain normal hydration, and given a specific medication called Cerenia (maropitant) to stop the vomiting. This drug has been a tremendous help in alleviating vomiting in pets due to many different causes. We use it for IBD and also for other GI problems like parvo virus and pancreatitis without IBD. Cerenia works on the emetic (vomiting) center of the brain.

Cerenia

We use the injectable version in the hospital, and send home an oral version if needed

Diet

It must be understood that if one of our doctors recommends a dietary change to treat your pet’s IBD that the only food or treat that can be fed to your pet is this new diet. Nothing else can be used as a food source. Feeding other foods is a reason why this dietary change does not work in some cases. When multiple people feed a pet this needs to be communicated to everyone.

Dietary intervention is considered a mainstay for many gastrointestinal cases because a large proportion of cats and dogs with gastrointestinal disease are associated with food-sensitivity. We need to get these pets eating again for the intestines to return to normal function.

Dogs and cats with pancreatitis, which is painful and causes severe illness,  do well initially with a low fat diet in the early stages to get them stronger and get the intestines used to digesting food again.  I/D (Intestinal Diet) has been used by our doctors for well over 35 years, and is the gold standard for pets with GI problems. After the pet is stable we look for a long term food.

PrescriptionDiet-ID

I/D comes in many variations, and our doctors will tell you which one is appropriate for your pet’s specific problem

Hydrolyzed Protein Diet

 It is the protein component of the food that causes the problem in IBD. Hill’s has solved this problem by making a food with a hydrolyzed protein that does not cause a reaction. It is unconditionally guaranteed, and is worth using in every case because it works often, and you can get your money back if it does not work. This is a complete diet and can be fed for the rest of your pet’s life. It is very rewarding when a dog or cat with the signs of IBD improves on only food and does not need medication.

PrescriptionDiet-ZD

The best food we have found overall for dogs and cats with food allergy is called Z/D

Novel Protein Diets

Novel proteins are not manipulated protein sources (as compared to hydrolyzed proteins like Z/D), but are simply new proteins that the pet has never ingested before. Many dogs and cats immune systems have not been exposed to venison, duck, or rabbit. Due to the fact that it takes long-term exposure to a protein before the immune system will react against it, then these novel protein diets are often attempted when the protein source is suspected to be the cause of IBD. The new diet will take at least 2 weeks, and up to 4 weeks, for the symptoms to diminish or resolve.

These foods might contain:

Potato

Duck

Sweet potato

Venison

Salmon

Vitamin supplementation is a critical component of treatment for some individual pets whose IBD stems from a deficiency in cobalamin (vitamin B12), specifically in cats.  Pets that are sick enough to have a low cobalamin level are generally in need of more than just vitamin supplementation, requiring a combination of other medications and dietary alterations.

Immune Modulators

Steroids (corticosteroids) are used in many cases in order to decrease the inflammation. The most common ones include prednisolone or prednisone. Budesonide, is a weaker steroid, that is also used. If the root of IBD or Triaditis is due to an immune-mediated process, then more potent immune system suppressants than steroids are required, such as cyclosporine, chlorambucil, or azathioprine.

Cyclosporine is an immune modulation drug that can suppress the inflammation from IBD.

Chlorambucil (Leukeran) is a chemotherapy drug for treatment of resistant IBD or some forms of cancer

Antibiotics

Antibiotics should be chosen based on bacterial culture and susceptibility when possible, especially in cases of Triaditis. Antibiotics such as Flagyl (metronidazole) are very commonly used for their ability to treat patients with chronic diarrhea. Some pets respond well to this medication only (they have Antibiotic Responsive Enteropathies). Flagyl suppresses the bacteria that are involved with IBD, and also mildly decreases the immune response that is an important component of IBD. Other antibiotics include Tylosin, Amoxicillin, and Fluoroquinolones. Tylosin must be compounded.

Probiotics and Probiotics

These are commonly used to help with the trillions of beneficial bacteria in the GI tract. IBD disrupts these “good” bacteria, and even the antibiotics we use to treat IBD can disrupt the normal GI flora. Make sure there is not a chicken or beef base.

Probiotics have bacteria that are considered to be beneficial to the GI tract. Probiotics have fiber that is fermented for good bacteria.

Liver Support Medication

When the liver is involved (Triaditis) we might also use Actigall (ursodiol) or Denamarin (s-adenosyl methionine)

Denamarin

IBD can be painful, and it is important to keep the pet as comfortable as possible during an acute episode of IBD or severe case of Triaditis. Prednisone, prednisone, and Flagyl decrease inflammation, which helps minimze pain. Specific pain medications are also used.

Stem Cells

Limited studies show promising results

Fecal Transplant

A last resort that can be effective. The feces must be negative for pathogens.

Prognosis

The prognosis depends on many factors. This disease is usually not cured, unless there is a food allergy and we find the right diet for your pet. Most cases are controlled with diet and medication. IBD and it’s associated diseases tend to be a long-term problem that is usually managed successfully. You increase your chance of success by giving medication consistently and bringing your pet to us for exams and diagnostic tests to look for changes that require a change in treatment.

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Spleen Hematoma

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This page stresses the importance of routine yearly exams, and close owner observation, on our pets. Large breed dogs can be stoic, and have significant problems brewing without showing any outward signs. When serious symptoms like weight loss and lack of appetite finally show up, the disease process is usually well entrenched, and there is little we can do. We want to see these pets before it gets to that stage.

Pets are masters at hiding illnes, so it can be difficult if they are ill. It might be a good idea to read our short page on symptoms of disease to know what to watch for.

We also have a nice page on teaching you how to do an in-home exam. If you bring your pet to us one of our staff will go over this with you, and do a hands-on demonstration of how to palpate the peripheral lymph nodes. This early warning system is a great way to catch problems early in the course of disease.

History

A beautiful male labrador retriever named Colt came in for a routine Wellness Exam when he was 10 years old. During this exam Colt’s owner told Dr. Palazzolo that Colt vomited on occasion over the last month, but that otherwise he was doing fine. He is a calm dog, and just lays around a lot.

Exam

Colt’s body temperature was normal, and his weight was the same as a previous visit. A pet’s weight is a good idea of how well it is doing, and if it is maintaining its weight that is usually a good sign. In Colt’s problem, this is not the case.

During the physical Dr. P noted a very tense abdomen, so tense that he could not even palpate internal organs. After this was noted, the owner did say that Colt’s abdomen seemed to be distended. The rest of Colt’s thorough physical examination was normal.

The distended abdomen is a significant finding, and warranted a radiograph, in addition to the blood panel which is part of the Wellness Exam.

Diagnostic Tests

ColtRad

You don’t need to be a radiologist to know something is wrong with this abdomen, as evidenced by the large and round whitish structure

NormalAbdDogRad

Here is a normal abdomen for comparison. In this normal radiograph you can see individual organs, unlike the abnormal one above, that looks like it has a beach ball inside of it.

This is a serious finding, and this mass could have many causes, and involve almost any internal organ. Due to its size, shape, location, and the relative lack of symptoms, it was probably the spleen. It could be a benign tumor of the spleen called a hemangioma, a malignant tumor of the spleen called a hemangiosarcoma, or a hematoma of the spleen. A hematoma is a blood filled cavity that is benign.

Its size said it might be a hematoma, which has the best prognosis of the three. To learn much more about spleen tumors please visit our hemangiosarcoma page.

ColtCleanChest

Before we proceed any further we take a radiograph of the chest to make sure there has not been any spread of tumor to the lungs. The white object in the center is Colt’s heart, the dark areas around the heart are the lungs. This is a normal chest radiograph.

You can learn much more about how to read a radiograph if you are interested

Our radiologist, Dr. Ann Reed, performed an ultrasound of the abdomen. This ultrasound lets us know if the mass is actively bleeding, and if there has been any spread of the mass to the right atrium of the heart. If that is the case, the mass is probably a hemangiosarcoma that has already spread. This is not a good prognosis.

ColtUS

Colt’s ultrasound report showing it is probably benign, and consistent with a hemangioma or hematoma

Pre-surgical Preparation

In Colt’s case there was no abdominal bleeding, and the heart was OK. Colt’s blood panel came back normal, so we did a cross match of his blood, and readied a unit of blood for a transfusion in case we needed it during the surgery scheduled for the next day.

Agglutination Crossmatch substrate Crossmatch blood Transfusion kit
BloodCrossMatch2 BloodCrossMatch1 BloodCrossMatch3 spleen-transfusion

Before we do a blood transfusion we do several tests to minimize a transfusion reaction

We were much better prepared for surgery the next morning with all of this information. During the night prior to surgery Colt was given intravenous fluids to stabilize him and make him a better anesthetic risk, and a pain patch was put on. Having the pain medication on board before surgery increases its effectiveness. Colt is now good to go for surgery the next morning.

We have a short page that talks all about how we do surgery at the Long Beach Animal Hospital. You might want to check it out before you see Colt’s surgery.

Graphic and bloody photos of surgery to follow

Colt did great overnight.  We took away his popcorn after the Lassie movie ended (he likes classic movies), and he rested comfortably during the night, monitored by our night crew. He slept well, and dreamed of being a famous movie star like Lassie.

ColtJenn

 Here he is with Jennifer the next morning, keeping an eye on our surgical team as they prepare for his surgery.

KennedyExam

Colt gets some extra petting for being a good boy, by his surgeon, Dr. Kennedy

KennedyExam1

Even though Colt has been thoroughly checked, we always perform a physical exam just prior to inducing anesthesia. An important organ to assess is the heart. If we suspect something is wrong with the heart when we listen to it we will do a pre-anesthetic EKG (electrocardiogram).

If you like heart stuff we have a very detailed page on heart disease in animals. It’s not for the “weak of heart” (pun intended), because it goes into all sorts of anatomy and physiology. If you get through it give yourself a pat on the back, and think of applying to veterinary school!

Propofol

Colt’s anesthesia is initially given by injection. Once he is relaxed we put in a breathing tube and start prepping his abdomen for surgery.

surgery-monitor

This surgical monitor allows us to detect any impending problems, and make adjustments before problems become serious.

Rabbit-femurfx-9

Even though we use these hi-tech machines to monitor important physiologic parameters during surgery, we also use the hands-on approach to make sure we do not miss anything. In this picture our anesthetist is listening to the heart with a stethoscope.

AnesthesiaReport

During the procedure Colt’s vital information is closely monitored and recorded. Our anesthesia page has more details.

Instruments

While Colt is being readied for surgery Dr. K is getting her instruments ready. She will need many clamps to close off the blood supply to the spleen before it can be removed, which required more than one surgical pack.

draping

When Colt is prepped, and under the proper plane of anesthesia, Dr. Kennedy does her draping. This draping is an important part of the surgery, and is doing carefully.

JessicaTerri

It will take more than one pair of hands to get this spleen out, so our surgical assistant, Jessica, stands by waiting for instruction. Terri our anesthetist keeps a close tab on everything.

Incision1

The initial incision is only though the skin. Blood vessels just under the skin are clamped before we go any further.

Incision2

You can see the two clamps that are controlling bleeding in the subcutaneous (SQ) tissue just under the skin. Colt’s spleen is humungous, so it will take a long incision to get a big enough opening to remove it

Incision3

Even though the incision was made as long as possible, the opening was still not big enough to remove the spleen. Dr. K had to make a side incision in the abdomen to facilitate removal.

SpleenBloodSupply

The spleen has an extensive supply of blood vessels that are near the stomach. A large part of this surgery is identifying and ligating these vessels, and doing this without damaging the blood supply to the stomach. These blood vessels are intertwined in tissue that is covering the spleen as the body attempts to wall of this large mass. This is the most meticulous part of the surgery, and Dr. K’s experience and skill at doing this before pays off.

LargeVessel

These blood vessels are large and need to be handled carefully

ClampingVessles

It takes multiple clamps and special suture material to perform this important part of the surgery

JessicaHoldingClamps

Jessica is kept busy holding clamps while Dr. K identifies and continues to ligate the many blood vessels to the spleen

FirstRemovalAttempt

As more of these vessels are ligated Dr. K carefully attempts to get the spleen out of the abdomen. No luck the first time.

Adhesion

An adhesion from the intestines to the spleen was identified and removed. Time to try to get the spleen out again.

SecondRemovalAttempt

 We need to be very careful at this point that we do not rupture the spleen by forcing it out.

FirstRemovalAttempt

With gentle coaxing and manipulating, along with Jessica’s help holding the abdomen open, we almost have it out, but not just yet

ThirdRemovalAttempt

It was time for Dr. P to stop taking photos and assist in surgery. He has removed many spleens in his decades of surgery, and with the help of Dr. K and Jessica, was able to extricate the spleen. Now Dr. K could finish ligating blood vessels (and hopefully Jessica does not need to scratch an itch at her nose)!

JessicaHolding

Here she is doing a great job

FinalCut

The final blood vessel to the spleen is cut while Jessica holds on to the spleen

JessicaHoldingFinal

After almost 2 hours of surgery Colt is now lighter on his feet

FourteenPounds

It’s official, 14.095 pounds!

SpleenHematoma

The vertical and long structure on the left is an enlarged and normal spleen, with the hematoma of this spleen on the right

Lavage

Surgery is nowhere near done. After Dr. K looks for any significant bleeding on the blood vessels she ligated, she flushes the abdomen numerous times with warm saline.

LineaSutures

The long process of putting Colt back together now begins. The most important suture layer is an area called the linea alba. This is where the muscle bellies of the abdomen meet, and is a tendinous area that is very strong. This is where the first and most important layer of sutures is placed.

SkinSutures

After more layers of sutures are placed, and before Dr. K puts in skin staples, Colt now has a bikini scar (OK, maybe not, but once the hair grows back nobody will know his secret)

Local

In addition to the pain patch put on the night before, and the pain injection given during surgery, a long acting local anesthetic is placed at the incision. Now Colt will be comfortable when he wakes up and through the night.

LocalStaples

All of our abdominal surgeries receive therapy laser treatment on their incisions. This aids in both healing and pain control. Notice the staples in Colt’s skin incision.

FirstBandage

Now comes the bandage; the first layer is gauze and telfa pads

SecondBandage

After more pads and gauze are put over the incision, the outer layer is wrapped by Terri while Jennifer and Jessica hold up Colt. They are getting their biceps exercise for the day!

LastBandage

We did the surgery the day after Halloween, so we thought this was an appropriate colored bandage

Trophy

Our dedicated surgical team posing with their trophy. Great job!

Colt was closely monitored for several days, and his red blood cell count was checked to make sure he did not need that blood transfusion. He went home after 2 days and was back to normal in no time. Yea Colt!

HemangiomaReport

Great news on Colt’s histopathology report, confirming it is a hematoma. Colt should make a complete recovery and lead a normal, if not lighter, life.

HemangiomaHisto

Just in case you want to see what a spleen hematoma looks like under the microscope here is your chance

047A8608

Colt with his happy mom two weeks later when he came in for his staples removal

 Case Summary

If you go back to Colt’s initial history the owner stated Colt vomited on occasion over the last month. Looking at the size of this hematoma (a record for Long Beach Animal Hospital), the hematoma was probably brewing over several months. Its a wonder Colt could even eat, and was not vomiting more, with a hematoma of this size in his abdomen. If Colt had not been brought in for his Wellness Exam, this hematoma could have easily ruptured, causing Colt to go into shock. and most likely a rapid death.

 Colt’s weight was the same as a previous visit. It was only because he had such a large mass in his abdomen, and goes to show you cannot go by just one physical parameter to determine health. It also shows you need to be thorough when investigating a medical problem.

The ability to do ultrasound with our highly skilled radiologist, telling us the hematoma was not actively bleeding, allowed us to take the time to prepare Colt for surgery. This made him a much better anesthetic risk, and and allowed him to heal faster with no complications.

The ultrasound told us it was probably a hematoma, and there was no evidence of spread to the heart which would indicate a potential malignant hemagiosarcoma of the spleen. With the blood panel and chest radiographs being normal, it was realistic to proceed with surgery based on the fact that the mass was probably not a malignant cancer.

Now that you have seen a successful hematoma surgery, now might be a good time to learn about hemangiosarcoma, a malignant cancer of the spleen. In this same page you can see another hematoma surgery of a dog with an 8 pound hematoma of the spleen.

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Geriatric Medicine

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In the past, we may have accepted a declining quality of life for our aging pets as a fact of life beyond our control. Like humans, older dogs and cats are more likely to encounter health problems than younger pets. Thanks to advances in veterinary medicine, pets are living longer than ever before. A 7 year old dog or cat is equivalent to a 50 year old person.

Most humanoids are practicing preventive medicine at this age- routine physical exams, breast exams, prostate exams, blood pressure checkups, blood panels and dietary changes. Dogs and cats need similar preventive medicine at this age. Since they age approximately 7 years for every 1 year of human life, an 8 year old dog or cat is equivalent to a 56 year old person, and a 9 year old dog or cat is equivalent ot a 63 year old person. This rapid yearly increase in equivalent age emphasizes the fact that we need to pay close attention to all dogs and cats as they move beyond 7 years of life.

Just as older people experience a progressive decline in physical condition, so do senior pets. Studies indicate that 36% of senior dogs suffer from osteoarthritis, 18% show signs of Cognitive Dysfunction Syndrome, and the number one diagnosed disease of dogs in all age groups is dental disease.

Compared to humans, old age problems may progress up to 7 times faster in senior pets. Having your senior pet examined only once a year is like a senior person visiting the doctor only once every seven years. That is why, as your pet nears 7 years of age (5 years of age in Giant Breeds), preventive senior exams every 6 months can help assess your pet’s current health, provide a baseline for monitoring changes in the years ahead, and help detect health problems in the early stages, when diseases can be treated more effectively.

Senior Care is “geriatric” medicine for pets. Senior health care implies both preventive and therapeutic approaches to medicine, including nutrition, dental care, and exercise as well as therapy for diseases.

Age Chart

Relative age of Your Dog in “Human Years”
Age Dog’s size in pounds
years 0-20 21-50 51-90 90 +
5 36 37 40 42
6 40 42 45 49
7 44 47 50 56
8 48 51 55 64
9 52 56 61 71
10 56 60 66 78
11 60 65 72 86
12 64 69 77 93
13 68 74 82 101
14 72 78 88 108
15 76 83 93 115
16 80 87 99 123
17 84 92 104
18 88 96 109
19 92 101 115
20 96 105 120
= Senior
= Geriatric

 


Symptoms

Changes in behavior or appearance may be the first indication of a problem. However, these signs may not be apparent in the exam room during your veterinary visit. It is important for you to watch for subtle changes, especially in stoic older pets.

Signs of aging:

Difficulty climbing stairs

Difficulty jumping up

Increased stiffness or limping

Loss of housetraining

Increased thirst

Increased urination

Changes in activity level

Excessive panting

Circling/Repetitive movements

Confusion or disorientation

Excessive barking

Less interaction with family

Decreased responsiveness

Tremors or shaking

Skin and haircoat changes

Changes in sleeping patterns

Less enthusiastic greeting or behavior

Altered appetite

Weight change

Common Health Conditions of Senior Pets

Obesity- As their metabolism slows down it is easy to overfeed. This leads to arthritis, sugar diabetes, liver disease, and heart disease.

Dental– Inflammation of the teeth and gums may lead to pain, infection, tooth loss, bad breath, kidney and heart disease, and, as a result, decrease your pet’s life expectancy.

Hormone (endocrine)- cause a vast array of symptoms that are treatable and sometimes curable.

Cushing’s– Excess production of cortisol (cortisone) by the adrenal glands

Addison’s– The opposite of Cushing’s

Diabetes (sugar) – Excess glucose in the bloodstream due to a lack of insulin

Hyperthyroid– Excess production of thyroid hormone

Hypothyroid– Inadequate amount of thyroid production

Kidney– Failure of this organ can lead to chemical imbalances, anemia, compromised immune function, and blood clotting defects as well as altered mental capacity. Kidney disease is a leading cause of death in geriatric cats.Chronic Urinary Tract Infections can easily occur without you being aware. These are painful, and can predispose your pet to bladder stones.

Liver– Failure can lead to serious disease with chemical imbalances, anemia, compromised immune function, and blood clotting defects as well as altered mental capacity.

Heart– Pets with heart disease can experience difficulty breathing, fatigue, exercise intolerance, and lethargy.

Cancer– Can occur in many different organs. Early detection may improve the prognosis. Many treatments are available and most have few side effects.

Cognitive Dysfunction Syndrome– Similar to senility or Alzheimers in people.

Skin conditions-Hair loss, itching, and skin infections are common

Arthritis-This is painful and debilitating, and can easily sneak up on a pet without you being aware of it.

High Blood Pressure– Usually secondary to a heart problem, kidney problem, or high thyroid problem.

Inflammatory Bowe Disease (IBD)- A common problem in cats as they age.

Epilepsy– These seizures have an unknown origin, and occur in older pets.

Senior Exam

With frequent checkups, at least twice a year, we can screen for common senior diseases. By diagnosing and treating problems earlier, we may be able to slow the disease process and prevent pain and discomfort.

In addition to a complete physical examinationdiagnostic tests can help detect many diseases before your pet displays signs of a condition. Even if results are normal, the findings give you veterinarian a good baseline to identify and monitor changes in your pet’s health as the years progress.

You can do an in-home exam to help catch problems before they become entrenched.

Physical Examination We can check for physical signs of cancer, arthritis, heart and lung disease, dental disease, or cataracts.
Complete Blood Count
(CBC)
This test helps identify infections, anemia, and certain types of cancer as well as problems with bleeding and the immune system.
Serum Chemistry Profile This blood test can help identify diseases of the liver and kidney, and endocrine disorders such as Diabetes or Cushing’s.
Complete Urinalysis A urine sample can help test for kidney diseasediabetes, urinary tract infections, and bladder stones.
Fecal Exam A fecal sample can be checked for internal parasites and bacterial overgrowth.
Other Tests Depending on your pet’s overall health, we may recommend additional tests such as blood pressure measurementradiographselectrocardiography (ECG or EKG),ultrasound, thyroid (hyperthyroid or hypothyroid) or adrenal gland (Cushing’s or addison’s) testing, as well as liver, pancreas, and small intestine function tests.

Here are examples of blood panels and urine samples that caught problems early, and before they became so well entrenched we would have a difficult time treating them.

This pet is anemic

This one has kidney failure

This low Specific Gravity is a sign of a kidney problem 

Senior Nutritional Needs

Nutritional needs of pets change as they get older. Senior dogs should consume fewer calories due to decreased activity and reduced daily energy needs. This is very important because obesity increases the risk of serious diseases, arthritis, diabetes, cardiovascular disease, respiratory disease, and musculoskeletal disorders in older dogs.

Pet foods, specifically for seniors, are now available with fewer calories, limited phosphorous, more protein, balanced fatty acids, antioxidants, vitamins and minerals to meet the specific nutritional needs of senior pets. These foods have optimum amounts of nutrition, and can help in the progression of common diseases like kidney disease.

All cats that are 7 years of age and older should be on Hill’s K/D due to the significant prevalence of this problem.

Many older dogs are obese and arthritic, and the Hill’s food Metabolic and Mobility is a major help for them.

We have much more information about nutrition in animals, and why you should never take the advice of a pet store or groomer on nutrition. It is an interesting read.

 


References:

1. Survey of Veterinarians, 1998. Sponsored by The Iams Company and Pfizer Animal Health.

Developed for Long Beach animal Hospital, by Glenna M Gobar DVM, MPVM, MS, courtesy of Pfizer animal Health; Sept 2001

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VNA (Veterinary Neuronal Adjustment)

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The goal of VNA is to treat the Vertebral Subluxation Complex (VSC). This is a functional defect of a joint which causes neurologic signs, or pain, that might not show up on an X-ray. The effects of VSC can include mobility problems, muscle spasm, neurologic defects and inflammation.

Disease related to the spinal cord has traditionally been treated with a combination of surgery and medication. Through the use of VNA, we now have another treatment modality to treat the spinal cord, thus helping all the organs in the body. VNA is a noninvasive and non-painful way to dramatically minimize the effects of spinal cord dysfunction. In most cases the improvement is so significant that we can diminish the use of medications, sometimes even stopping them altogether. This page will give you a detailed explanation of the use of Veterinary Neuronal Adjustment (VNA) at the Long Beach Animal Hospital.

This treatment method used to be called VOM (Veterinary Orthopedic  Manipulation). You might encounter this name still in the literature.

We have a few videos at the end of this page to show how it is used on actual patients.

Spinal Cord Anatomy

The spinal cord is an extremely sensitive and complex part of the nervous system. In essence, it is an extension of the brain. Subtle changes in pressure on the spinal cord itself can cause significant changes in the body. The spinal cord is completely enclosed in bone for protection. To allow for movement, and to allow nerve branches to leave the spinal cord, it is flexible and has openings.

This view of a spinal cord model is an end-on view of how the spinal cord fits into the spinal canal. You can see how the spinal cord is enclosed by bone. If it swells it has no place to expand into, resulting in serious damage to the cord. This swelling can occur when VSC is present.

The above picture greatly simplifies the anatomy of this area. In reality, there are many blood vessels, nerves, muscles, and connective tissue all around the spinal cord.

This diagram shows some of the complexity that is not so apparent in the simplified picture above.

The Nerve Roots (NR) above are the same thing as the Dorsal Nerve Root in the picture below. The Spinal Cord (SC) in the picture above is the semicircular area in the top left of the picture below. When a vertebrae becomes subluxated (misaligned) it affects these nerve roots and ganglia. This leads to the disease we call Vertebral Subluxation Complex (VSC).

As the spinal cord moves from the brain down to the tail it sends out nerve branches (called nerve roots- see picture above) that go to various organs. These branches are part of the Autonomic Nervous System (ANS). The ANS is an extremely complex system of nervous connections that runs the length of the spinal cord. Nerves that branch off from these connections innvervate all the important organs in the body. The ANS performs it magic without your conscious input. Here are a few examples of the many things the ANS does:

  • Dilates your eyes when you are scared
  • Increases your heart rate when you are scared
  • Contracts your stomach and opens your pylorus to allow food to move into the intestines
  • Stimulates your pancreas to secrete digestive enzymes into the small intestines as food moves past
  • Dilates or constricts blood vessels to the internal organs. This becomes an important point when we treat diseases of internal organs like the kidneys.

In this picture you get a feel for the complexity of the ANS. As the nerve roots leave a vertebral segment they form ganglia that innervate the internal organs. This is how the VSC can affect internal organs.

To use this diagram look at the middle of the thoracic vertebrae on the left. Go to the right until you see the Celiac ganglion. A branch of this ganglion innervate the kidneys. When the vertebrae in the middle of the thoracic area have VSC they kidneys can be affected. When treated with VNA the nerves that supply the kidneys with normal blood flow become dilated. This increases blood flow to the kidneys, and helps them if they are diseased.

When the vertebrae in the picture above are misaligned only slightly there can be significant disruption to the spinal cord and the nerve roots as they leave the spinal cord. Correcting this problem is the goal of VNA.

Vertebral Anatomy

The dog has 31 vertebrae:

  • Cervical (neck)- 7
  • Thoracic (chest) – 13
  • Lumbar (lower back) – 7
  • Sacral (pelvis) – 3 (fused)

Let’s go on a tour of this anatomy by looking at overlapping radiographs:

C-1 and C-2 are called the atlas and the axis. The words atlas (holding up the world) and axis (what the world spins on) come from Greek mythology. There can be an instability in this area in large dogs that will cause neurologic problems. The cervical vertebrae are quite flexible, for obvious reasons. VSC can occur in this area.

As the cervical vertebrae become the thoracic vertebrae they go past the shoulder (S). The nerves that come off this cervical-thoracic junction at the shoulder are called the brachial plexus (you cannot see nerves on a plain radiograph). They innervate the front legs on each side. Each of the thoracic vertebrae corresponds to a rib (R) on each side of the chest.

As we continue down the thoracic vertebrae you can visualize how high their dorsal spinal processes are. Also notice how these processes start to get smaller as we get closer to the lumbar vertebrae.

Moving towards the end of the thoracic vertebrae we come to what is termed the thoracolumbar (T-L) junction. It is a very common area to have VSC disease. As we pass into the lumbar vertebrae we have now made our way into the lower back.

The 7 lumbar vertebrae eventually lead into the sacral vertebrae (S). The fused sacral vertebrae are hard to visualize because they are within the pelvis. After the sacrum we are at the tail.

This side view of a spinal cord model shows 2 vertebrae (V) with a normal disk (D) in between. One of the nerve roots (NR) can be seen coming off of the spinal cord (SC). You saw this same picture, from a different angle, at the beginning of this page.

To keep you oriented, this is the same area on a radiograph (at L1-2). The nerve root comes out of the dark structure that looks like a horse’s head. The disk, nerve root, and spinal cord do not show up normally on a radiograph. This is one of the areas on a radiograph we look for VSC, although many times VSC can be present and there are no radiographic changes. If radiographic changes do occur, they can take months to years to become apparent on a radiograph.

VNA Theory

Lets review some of the concepts we illustrated above. alterations in the biomechanical or physiological dynamics of the joints of the vertebral column (called a subluxation because the bones are partially dislocated) cause spinal nerve dysfunction as the nerve roots leave the spinal cord. This is VSC. The dysfunction can lead to mobility problems in the joint, swelling and inflammation in the joint, or spasms of the muscles immediately around the vertebrae. The nerve root that has a dysfunction causes disease in many internal organs that are innervated by a particular nerve root.

The negative forces that caused the dysfunction in the first place are from trauma and environmental toxins. Most pets have had significant trauma to their spinal canal since they were young. It comes in the form of playing with a Frisbee, jumping off or onto something, general play, and excessive running. For some pets, going down stairs might be the biggest predisposing factor to subluxation. We recommend harnesses for most dogs since collars put extra strain on the neck and might predispose to VSC.

In many cases, the changes in the vertebral column that surround the area of nerve dysfunction do not show any changes, and thus are normal on a radiograph. When radiographic changes of this nerve dysfunction are present, they occur long after the problem originated. In some cases the nerve dysfunction from the subluxation can be low-grade or intermittent, taking years to show up on a radiograph.

In VNA we counteract nerve dysfunction by “re-setting” the joint with a gentle and painless force. We are counteracting all of the negative forces that have built up on the spinal canal and its nerve roots over a period of time. The nerves in the area can begin acting normally again, which increases blood flow to internal organs, correcting many diseases. Some of the diseases that are responsive to VNA therapy include:

VNA excels at treating Feline Hyperesthesia. In this disease cats are extremely sensitive on their skin to stimulation, especially the rear quarters. Most cats will lick obsessively when scratched here, others are so sensitive they will go into a seizure.

This cat has a moderate form of hyperesthesia. Click on his picture to see a video of how sensitive he is.

Click on his picture below and watch how we treat him. Notice how relaxed he becomes when he lays down as the treatment starts. Also watch how he starts licking as the vetrostim moves down his back

The nature of this technique allows us to detect disease states before clinical symptoms appear, allowing us to initiate treatment before your pet exhibits clinical signs of disease. This means that we now have at our disposal a tool to determine if your pet is starting to get a disease before the disease becomes well entrenched. This approach is far superior to allowing a disease to become entrenched, and thus is not as easily treated. When treated at this early stage the disease process can be minimized, and sometimes even eliminated. In a sense, VNA is a form of preventive medicine.

The arrow points to vertebral changes that occur secondary to nerve dysfunction. In this radiograph the body is trying to stabilize a subluxated vertebrae by laying down extra bone. Unfortunately, these changes on the radiograph become apparent many months to years after the initial incident that caused the nerve dysfunction. With VNA we now have a diagnostic and treatment capability to prevent these severe boney changes from establishing themselves.

Equipment

Activator (spinal accelerometer)

This devices fires a very fast and concise force to the subluxated vertebrae. It takes at most 4 milliseconds to administer this force. The fast speed of the accelerometer, combined with its small mass, allows us to administer a concise force only to the problem area. Since there is no pain involved, anesthesia is not needed.

This is the manual activator.

The activator is pain-free. This brief movie shows us using it on our hands. Turn up the volume so you can hear the sound it makes.

Activator Movie

The movie shows it in actual use along the lower back of a dog

Using Activator on a Dog

In most pets we use an electric activator because it is much faster, easier on the hands, and has adjustable power settings.

Technique

The first thing we do is try to determine where in the spinal canal nerve dysfunction is occurring. There are several ways to make this determination.

Routine Diagnostic Tests

Every pet that is presented for a problem should have routine tests performed after its examination. These tests usually include a blood panel with thyroid test, a urinalysis, a fecal sample for internal parasites, and radiographs of the spine. You can learn much more about these tests by going to our Diagnostic Tests page.

Not every pet with a disease has a vertebral subluxation causing nerve dysfunction. There can be foreign bodies, infections, and even tumors causing problems.

The white area on this radiograph is a tumor, verifying the importance of taking a radiograph before initiating treatment. This tumor is not treated with VNA.

Neurologic Reflexes

There are several reflexes to help us pinpoint areas of subluxation causing nerve dysfunction:

Panniculus

Animals have a muscle under the skin (the cutaneous trunci muscle) that allows them to flinch their skin, unlike humanoids. This is a great advantage to them when they want to rid their haircoat of pesky insects, but have no hands to scratch with. When the dorsal or lateral process of the bones of the vertebrae from T-3 to L-6 have a dysfunction, the skin in the lower to mid back will flinch, indicating a problem. Sometimes the problem is so apparent that just pushing gently on the spine in this area will cause the skin to flinch. In many cases though, we need to gently stimulate the area with the activator to elicit this response.

This gives you an idea of the relative position of the activator when we test for this response.

To initiate this response we place the activator over the dorsal spinous processes of the vertebrae and look for the response as we set off the activator. We start at the vertebrae of the neck and work all the way back to the pelvic bones, noting areas where there is muscle or skin movement. This movement is also called a “read”. A positive read indicates an area of subluxation. These reads will change when we actually treat the area, which is an indication that we are affecting a cure.

Medications, particularly anti-arthritic medications will make it difficult to interpret reads. If your pet can be taken off these medications without any serious effects it will help make the reads more accurate.

Ear and Facial Reflexes

In the C-2 to T-10 area there is a reflex in animals that shows up as an ear twitch. Sometimes a pet will look like it has this reflex when it is really only reacting to the slight clicking sound of the activator.

Postural Reflexes

When an animal stands it maintains tone to the extensor muscles of the legs. A spinal segment that has a problem will temporarily shut down the signal to these extensor muscles when stimulated, causing a momentary change in posture. This change can be very subtle, and might range from a yawn to a twitch, stumble, collapse, or sign of pain. Sometimes the only indication of this response is a subtle change in posture that is felt by the person holding the pet.

Once we have determined if there is a subluxation, and where it is most likely to be by analyzing our diagnostic tests and checking for reflexes, we initiate treatment. The activator is also used to treat, making the same pass as the initial one where we determined likely areas of subluxation. We pass the activator at least 2 times in most cases, and look for changes in the reads.

We put the activator directly over the dorsal vertebral process you saw in the picture above. There is a significant amount of muscle and tendon (and sometimes fat in obese pets!) surrounding the dorsal vertebral process. On heavy coated pets there is even more to go through to transmit the energy directly to the process.

One of the effects of the vertebral subluxation is muscle spasms in the muscles along the back. If we stimulate this area we can relieve the muscle spasm, causing a return to normal posture and relief of pain and discomfort. Stimulating the muscles over the vertebrae also stimulates nerve centers (called ganglia-remember the pictures above?) that reside along the vertebrae.

The instrument we use to stimulate the muscles and ganglia along the vertebrae is called the VetroStim. Most pets love it because it feels like a massage!

You can see the relative position of the VetroStim when positioned to stimulate muscle around the ganglia

This close-up shows how we position it over the muscle, and not the dorsal process of the vertebrae

In this movie you can see the activator and VetroStim in action. We start at the neck and rapidly move to the lumbar vertebrae. Turn up the volume to hear the sound the machine makes.

Activator and VetroStim use on a Beagle

Pets that have internal problems like urinary incontinence and inflammatory bowel disease are treated at their Somato-Visceral points.

These areas are located near the angle of the jaw on either side.

Several of our clients were so satisfied with their pets outcomes that they starred in a little movie……

We do VNA on a wide variety of animals, including this is Iggie that was not moving its rear legs properly

We have even used it in an egg bound bird to help pass a stuck egg.

Complications

VNA does not work well if your pet has underlying problems. They need to be corrected to get the full advantage of VNA treatment. Three common problems that need correcting are:

Nutrition- your pet needs to be on a food certified by the Association of American Feed Control Officials (AAFCO).

Hypothyroidism can interfere with treatment. If your dog has this problem it needs to be supplemented with thyroid hormone. In many cases treating this problem with VNA can affect a cure down the road.

Hyperthyroidism also poses a problem, and needs to be treated if present. VNA therapy might also affect a cure for this problem.

Treatment Timetable

In most pets we treat at day 1, day 3, day 7, then twice per week,  and then every 1-4 weeks depending on response. At that point we treat monthly for 3 months.

For the typical dog it takes a total of 5-6 adjustments to make a cure, for the cat it takes 4-5. Some pets respond well initially, and seem to be symptom free after only several treatments. These pets are not cured yet, and should be treated until there are no more reads. Our goal is to affect a cure, and then treat only once every 3-6 months to maintain the cure. The Feline Hyperesthesia Syndrome can take up to one year to cure in some cases.

Every pet is an individual, so your exact treatment timetable might be modified by one of our doctors as treatment progresses. It is important not to let your pet jump into the car or from the front seat to back seat on the way home from our office. This can cause an adjustment to fall out of place.

 

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Intestine Tumor in a Cat

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Tumors are common in cats, especially as they get older. This page describes how we treated an intestinal tumor in an 11 year old cat named Ruby. The format in this page will be different than our other disease pages. In this one we will present it as a case study, and show the diagnostic process that allowed us to make this diagnosis.

We will follow the parameters of the diagnostic process in this case, the same process we use in every diagnosis me make. If you are not familiar with this process click here  for a quick review, then come back to this page and continue the case study. You need to have an understanding of the diagnostic process in order to appreciate the thought process involved in making Ruby’s diagnosis.

This page has graphic surgical pictures.

Signalment

Our patient is an 11 year old spayed female domestic short haired cat named Ruby.

Interpretation of signalment:

Domestic short haired cats have no breed predilection, so this information does not narrow down the list of possible diseases at this point. Since Ruby is spayed there is negligible chance of a reproductive problem like pregnancy or an infected uterus, called a pyometra.

Her age is very important because it brings to mind some of the following diseases:

History

Ruby has been lethargic and not eating for 2 days. She seems painful when picked up and has been vomiting a yellow fluid. Other important parameters like bowel movements, breathing, and urination are normal.

Interpretation of history:

This information is helpful because now we start getting a feel for the extent of Ruby’s problem. It is unusual in that she is vomiting and has not eaten in 2 days, yet her bowel movements and urination are normal. A pet that has these symptoms is almost always dehydrated and would not be having normal bowel movements and urination. This discrepancy in the history is not uncommon in many cases.

Because of the new information we obtained in Ruby’s history, we need to add infection, intestinal foreign body, abscess, liver diseaseFeLVFIVFIPkidney diseasehyperthyroidism, and even poisoning to her potential disease list.

Physical Exam

  • Temperature- 104.3 degrees F
  • Weight 12.75 #
  • Eyes- normal
  • Ears- normal
  • Oral Cavity- normal
  • External Lymph Nodes- normal
  • 8-10% dehydrated
  • Heart- normal
  • Lungs- normal
  • Abdomen- 4 cm x 4 cm mass palpable in the mid abdomen
  • Muscles and Bones- normal
  • Skin- normal
  • Interpretation of exam findings:Our exam findings give us important information. Ruby has a fever (normal cats are usually less than 103 degrees F). She is dehydrated, as was expected from her history. We make a determination of her state of hydration by looking at the color of her gums, checking if her eyes appear sunken, and noting how elastic her skin is when we pull it up and let it go. The fact that she has a mass in her abdomen is one of our most important findings so far.Based on the information we have at this point we can now generate a list of Ruby’s problems:
    • anorexia (not eating)
    • Lethargy
    • Emesis (vomiting)
    • Pyrexia (fever)
    • Dehydration
    • Abdominal mass

Differential Diagnosis

This is one of the most important parts of our diagnostic process. It is a list of the most likely diseases that are causing Ruby’s problem. Based on this list we will perform specific diagnostic tests to narrow the list down to the most likely disease processes occurring. We will also institute treatment based on her problem list and the differential diagnosis. We always initiate symptomatic treatment before our test reports return. This decreases our patients’ discomfort as soon as possible, and allows us to treat the problem earlier which is always an advantage in healing.

  • Infection
  • Intestinal tumor
  • Lymph node cancer
  • Feline viral disease
  • Kidney Disease
  • Liver Disease
  • Splenic disease
  • Pancreatic disease
  • Intestinal inflammation/abscess
  • Intestinal foreign body
  • Stomach disease
  • Constipation
  • Intussusception- A disease where the intestines literally telescope into each other. This obstructs the flow of food through the intestines, and can lead to death of a section of the intestine.

Diagnostic Tests

By running diagnostic tests we rule in or rule out the diseases in our differential diagnosis list above. In Ruby’s case we initially ran a blood panel and took an x-ray.

Blood Panel

The blood panel revealed an elevation in her white blood cells. Tests of the liver, kidney, pancreas, red blood cells, protein, and viruses were all normal.

X-Ray

radiograph was taken of Ruby’s abdomen. The stomach, kidneys, large intestines, and bladder all appeared normal. The liver was slightly enlarged (called hepatomegaly). There was a large soft tissue mass effect in the center of the abdomen.

Here is a normal cat abdomen radiograph- compare it to Ruby’s below. The normal organs are identified:

L- Liver
S- Stomach
K- Kidney
LI- Large intestine
SP- Spleen
SI- Small intestine
BL- Urinary bladder
The white arrow points to sutures from a spay surgery

Here is Ruby’s radiograph. The large white section in the lower center is the problem area. This is where the small intestines (SI) are in the above radiograph. Can you see the liver, stomach, and kidneys?

A tiny needle was inserted into the mass in her abdomen and some cells were removed for analysis by a pathologist. This test is called an aspirate, and the analysis of these cells is called cytology.

Interpretation of diagnostic tests

The normal blood panel, except for the elevated white blood cell count, minimizes the chance of liver, kidney, and feline viral diseases. The x-ray eliminates constipation as a cause to Ruby’s problems. The report from the cells taken from the abdomen indicates there is infected or dying tissue in the abdomen. This is a serious finding and necessitates immediate action.

Based on these test we can now refine our differential diagnosis:

  • Ruptured intestines
  • Intestinal abscess
  • Intestinal cancer
  • Intestinal foreign body
  • Lymph node cancer
  • Pancreatitis
  • Spleen mass
  • Intussusception
  • Liver mass
  • Kidney mass
  • Lymph node mass

A determination had to be made as to the appropriate course of action for Ruby’s condition. This is based on her age, cost, convalescence, and prognosis. These important points are discussed with Ruby’s owner prior to any further treatment. The main decision for her owner at this point is to perform ultrasound versus surgery. Each has its advantages and disadvantages:

Ultrasound advantages

No anesthesia is required and Ruby does not have to undergo the trauma of surgery in her abdomen. Ultrasound is very accurate, the results of the ultrasound are immediate, and biopsies can be obtained accurately. With the ultrasound an expert can literally visualize the internal structures of an organ and make a determination on whether or not it looks healthy.

Here is a typical ultrasound picture on a different case. It is looking at the liver and gall bladder. By looking at the liver closely an experienced doctor can determine if the cells in the liver are abnormal. If they are abnormal the ultrasound is used to guide a special biopsy needle right to the problem area.

Our ultrasound doctor is giving us a demonstration of how the biopsy is obtained.

Only a small amount of tissue is obtained with this method. When analyzed microscopically by a pathologist a significant amount of information can be obtained.

Ultrasound disadvantages

Surgery might be inevitable, so why delay. No treatment can be given with ultrasound, it is for diagnostic purposes only. Delaying prolongs the time it takes to ultimately correct Ruby’s problem and adds additional costs to the bill if we do proceed with a laparotomy.

Exploratory surgery advantages

An exploratory surgery in Ruby’s abdomen is called a laparotomy. It has the advantage of giving us an immediate diagnosis and gives us an opportunity to treat the condition (if the problem is not too far gone). Also, the surgeon can literally see the internal organs in their natural color instead of grey images on an ultrasound screen.

Exploratory surgery disadvantages

It is a an invasive procedure that has risks, including the anesthetic risk. Even though the surgeon can palpate internal organs, he can not look at their internal architecture like the ultrasound does. Also, there is  post operative discomfort and convalescence when a surgery is performed. With modern anesthetics and pain medication we can do almost any surgery in an older pet and not have any problems.

In Ruby’s case a decision was made to perform a laparotomy. We were fairly certain of our diagnosis and the need for surgery, so why prolong the inevitable.

Treatment

Treatment was initiated as soon as Ruby was admitted to the hospital This treatment consisted of intravenous fluids to correct her dehydration and lethargy. She was also given intravenous antibiotics and fed a special food. Her temperature was also closely monitored. Here is a picture of part of her medical record on the day of surgery:

Status BAR means she was bright, alert, and responsive Weight- 12 # 11 ozTemperature- 103 degrees F Appetite- NPO means “nothing per os”. This is a Latin abbreviation for no food given in anticipation of surgery. Urine- NormalBowel movement- noneOur nurses noted that she had vomited during the night and she was scheduled for a laparotomy surgery sometime today. Her treatment consisted of lactated ringers solution. She was given 250 milliliters intravenously every 12 hours. Baytril, her antibiotic, was given at 1.3 milliliters intravenously every 12 hours.

Surgery

The following area contains graphic pictures of an actual surgical procedure performed at the hospital.

Ruby was anesthetized and brought into surgery when she was anesthetically stable. A 7 inch incision was made in her abdomen and her internal organs were assessed.

We suspected Ruby’s problem was with her intestines, so we immediately assessed them. The diseased area was found and brought out through the incision in her abdomen. Not only were the small intestines swollen and discolored, there was a ruptured area of infection and dead tissue. The oval mass in the picture below is a tumor in the small intestines. There is an opening in the center where it is dead and has ruptured into the abdomen.

This section had to be removed without damaging the rest of the intestines. This is a delicate procedure because the intestines have a tremendous blood supply that can easily be injured during surgery. Special clamps (seen in the picture above) are used to separate the diseased tissue from the normal intestines. Once they are in place the blood supply to the diseased part of the intestine is cut off.

In this picture the larger black arrow on the top points to the diseased intestine, while the smaller 4 arrows in the center point to metal clips that have cut off the blood supply to the disease intestine.

After cutting its blood supply the diseased tissue is removed by cutting between the 2 clamps. The clamp on the right (arrow) is on the diseased portion of the small intestine. The clamp on the left (arrow) is a very gentle clamp that keeps any intestinal fluid from spilling out of the cut end of the normal intestine. We are using the scalpel blade to make the actual cut between the 2 hemostats.

The opening of one end of the normal intestines is now visible towards the right immediately after it has been cut. The center of this opening is lined with pink tissue called the mucosa, the white area around it is called the submucosa. The submucosa is thicker than normal, indicating that there might be additional disease in this section and further intestine might need to be removed.

The tedious process of suturing the cut ends of the intestines (called an anastamosis) begins. These sutures are critical if there is to be healing and to prevent leakage of intestinal contents into the abdomen when this pet eats. The first suture is shown being placed as the process is begun.

Part way through the suturing you can see the intestines coming together nicely. The bleeding is a good sign because it is a general indication of healthy small intestine.

When all of the sutures are placed a small amount of sterile saline solution is injected into the anastamosis site to check for leakage.

This is a good overall view of the anastamosted section of intestine (see arrow). You can see how this section of small intestine is more inflamed than the normal section below it.

With the intestinal problem corrected we explore the rest of the abdomen for any other problems. Nature works in complex ways, and just because we found a problem in one area does not mean all the other abdominal organs (including more intestine) are disease free. This picture shows a normal spleen in the top left along with normal intestines on the bottom.

The diseased tissue had ruptured which means there is an infection in the abdomen (this is called peritonitis). To alleviate this infection we flush the abdomen with copious amounts of warm saline solution. This picture shows our suction apparatus removing some of the fluid that was flushed into the abdomen.

Here is Ruby just after surgery. She is a little groggy from the ordeal, but her pain medication has been administered so she is comfortable. She will be monitored closely and given some broth 12 hours after surgery. Within 24 hours after surgery she will be nibbling soft food.

Final Diagnosis

Ruby had a tumor in her small intestine called a Mast Cell Tumor. Compared to most abdominal tumors we diagnose it is a relatively rare form of tumor, and it is seen only in the cat. There is the possibility that it might spread to intestinal lymph nodes or even liver later in its course. It is difficult to say what will happen in the long term, so her prognosis is guarded.

In addition to the surgery we put Ruby on medication to minimize side effects from the tumor. Mast cell tumors have the potential to release a compound called histamine. This can cause a type of allergic reaction and even cause ulcers in the stomach lining. Ruby is on medication to counteract this problem.

Ruby returned to have her stitches removed 2 weeks after the surgery.

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Cushing’s (Hyperadrenocorticism)

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Cushing’s Disease (also known as hyperadrenocorticism- Cushing’s is easier to pronounce, so stick with that word) results when the adrenal glands secrete an excess amount of cortisone. It is the most common endocrinopathy (hormone disease) encountered in older dogs. This disease is the exact opposite of another endocrine problem in dogs called Addison’s disease (hypoadrenocorticism).

This detailed page will emphasize Cushing’s disease in dogs, with an explanation of how it differs from cats at the end. This is a complex hormonal disease that does not lend itself to a simple explanation or an easy diagnosis. Some pets have the symptoms, yet the tests are negative. Other pets have positive test results, but minimal symptoms that do not warrant treatment. Pace yourself-you might want to go to the bathroom before attempting this page!

We have a summary page on Cushing’s if the explanation on this page is too detailed for your needs.

This page contains graphic photos.


Several medical terms and abbreviations relate directly to Cushing’s:

cortisol– cortisone produced by the adrenal glands atrophy– decreased size of an organ
exogenous cortisone– supplemental cortisone hypertrophy– increased size of an organ
HAC – hyperadrenocorticism polyuria– excess urinating
CRH– corticotropin releasing hormone polydipsia– excess drinking
polyphagia– excess appetite PU/PD– polyuria and polydipsia
glucocorticoids– mostly cortisol, and a small amount of cortisone mineralcorticoid-hormone that affects sodium and potassium
hypoglycemia– low blood glucose level iatrogenic– caused by something a person does as opposed to happening naturally.
adrenalectomy– surgery to remove the adrenal gland. ACTH– adrenocorticotrophic hormone
hepatomegaly– enlarged liver adrenomegaly– enlarged adrenal gland
anabolic steroid– testosterone and its equivalent PD– pituitary dependent
catabolic steroid– cortisol and its equivalent AT– adrenal tumor

Anatomy

The adrenal glands are small paired glands buried in fat in the front of each kidney. Even though they are small, the cortisol they secrete, along with their other functions, have great significance to normal physiology. These guys are small but mighty, as you are about to learn!

The arrows point to the paired adrenal glands in front of each kidney. The extensive blood supply to the kidneys and adrenal glands is apparent. In the diagram they are easy to see. They are not so easy to see during ultrasound or exploratory surgery because normally they are small and buried in fat. They do not show up on an X-ray unless they are calcified.

Adrenal-Normal

A normal adrenal gland of a dog buried in fat just above the kidney. The white structure is the tiny adrenal gland, the dark structure below it is called the Phrenicoabdominal vein. It is a large vein for such a tiny organ, a testament to the importance of the adrenal gland.

Cushings-FerretAdrenal2

This is a normal ferret right adrenal gland, just under a lobe of the liver, which is pulled forward by the surgeon’s fingers

Cushings-FerretAdrenal1

This is a normal ferret left adrenal gland (just above the hemostat) buried in fat. The left kidney is the structure to the right.

Cushings-FerretAdrenal3

This is a picture of an enlarged left adrenal gland (arrow) that is buried in fat near the kidney (K). I is from a ferret that has adrenal gland tumor, so the gland is inflamed and easy to visualize. This is not necessarily the case in dog and cats with adrenal gland tumors.

The internal architecture of the adrenal gland is made up of several distinct zones.

  • Cortex

    The cortex (outer shell) of the adrenal gland is made up of 3 anatomical parts:

    • Zona Glomerulosa

      This is the outer layer of the adrenal gland. This section secretes the mineralcorticoid aldosterone. Aldosterone is vital to proper sodium and potassium regulation. Aldosterone has a role in maintaining blood pressure.

    • Zona Fasciculata

      This is the next layer as you go inward, and produces the glucocorticoid cortisol. The cells in this area are the ones that cause Cushing’s.

    • Zona Reticularis

      As we continue inward we come across this section that secretes the sex hormones known as androgens (male sex hormones), estrogen (female sex hormones), and sex steroids. These are usually secreted in such small amounts as to be of no major significance in healthy animals.

  • Medulla

    This consists of the very center of the adrenal gland. It secretes hormones called catecholamines. The two important ones are epinephrine (adrenaline) and norepinephrine.

Physiology

These tiny organs have a profound influence on many internal organs. The hormones they secrete work in unison with other internal organs, particularly the liver, and have an enormous effect on physiology. These hormones interact with many other hormones that have the opposite effect, usually in some type of feedback mechanism that is monitored by the brain. This interaction is complex, so only a summary of adrenal hormone physiology is presented.

The adrenal glands secrete several important hormones, most of which are synthesized from cholesterol. We will explain 3 of them; cortisol, aldosterone, and epinephrine:

  • Cortisol

    Cortisol is a hormone that is essential for life. Cortisol maintains a normal blood glucose level, facilitates metabolism of fat, and supports the vascular and nervous systems. It affects the skeletal muscles, the red blood cell production system, the immune system, and the kidneys.

    It is considered a “catabolic steroid”. This means it takes amino acids from the skeletal muscles and, with help from the liver, converts them to glycogen, the storage form of glucose. These functions are the exact opposite of “anabolic steroids”, the drugs that weight lifters take to increase muscle mass. The end result of this is an increase in the level of glucose in the bloodstream. The hormone called insulin has the opposite effect on blood glucose, adding to the complexity of this system. You can learn more about insulin by going to our diabetes mellitus page.

    The level of cortisol in the bloodstream continually fluctuates as physiologic needs vary. Surgery, infection, stress, fever, and hypoglycemia (low blood sugar) will cause cortisol to increase. This continual fluctuation adds to the difficulty of diagnosing Cushing’s, because the amount of cortisol in the bloodstream is so variable.  A test taken at one moment in time might have different results if taken later.

    To control the level of cortisol the hypothalamus and pituitary gland in the brain secrete chemicals into the bloodstream called releasing factors. In the case of the adrenal glands , the hypothalamus secretes a hormone called corticotropin releasing hormone (CRH). It goes to the pituitary gland and stimulates it to release a hormone called adrenocorticotrophic hormone (ACTH). It is the amount of ACTH circulating in the blood stream that tells the adrenal glands (specifically, the cells at the zona fasciculata) how much cortisol to secrete. There is a negative feedback loop that allows the hypothalamus and pituitary gland to refine precisely how much cortisol circulates in the bloodstream. The more cortisol secreted by the adrenal glands, the less CRH and ACTH secreted. This allows the body to precisely refine the level of cortisol, and to change the level rapidly due to changing physiologic needs.

    Numerous internal organs are affected by cortisol:

    • Muscles

      Cortisol is needed for proper muscle action, yet too much can cause the muscles to atrophy (shrink). This is due to their catabolic effect. This means that they literally cause the body to break down the amino acids in the muscle fibers in order to increase the blood glucose (sugar) level. Cortisol does this in a complex mechanism that involves the liver. The end result is the muscles become smaller. When this occurs at the abdominal muscles the abdomen appears pot bellied.

    • Bone

      Bone is made up of a protein matrix and calcium, both of which are affected by cortisol. Excess cortisol affects the protein matrix, decreases calcium absorption from the intestines, and increases calcium excretion by the kidneys. Skeletal mass decreases and bones become weaker.

    • Skin

      It causes atrophy of hair follicles and sebaceous glands, which leads to alopecia (hair loss). Elastic tissue under the skin is also affected, leading to thinner skin and adding to the pendulous abdomen. The disruption in the elastic tissue of the skin can also cause calcium changes in the skin. This might lead to areas where calcium builds up in small nodules. In cats the skin changes can become severe, and are referred to as fragile skin syndrome.

    • Vascular System

      Cortisol is required for maintaining the integrity of the lining of blood vessels. An excess will lead to thinning of these walls and the potential for rupture. The end result is a hematoma. Cortisol also increases the number of circulating red blood cells and helps maintain blood pressure.

    • Central Nervous System (CNS)

      Cortisol is necessary for the normal maintenance of brain functions. It can interfere with sleep and change the mood. You might notice these effects if your dog has Cushing’s or is given supplemental cortisone for treatment of a disease.

    • Liver

      Excess cortisol will increase the workload on the liver as it converts amino acids to glycogen. Pets with Cushing’s will commonly have an enlarged liver, known as hepatomegaly. You will be shown a picture of an enlarged liver on an x-ray in the diagnosis section.

    • Kidney

      An increase of cortisol increases the blood flow (also called GFR-glomerular filtration rate) to the kidneys. This will result in an increase in the amount of water and waste products filtered by the kidneys. Our kidney disease page has more details. This is one of the reasons why dogs with Cushing’s drink and urinate excessively (PU/PD), and urinate a dilute urine.

    • Immune System

      This is one of the more profound functions of cortisol. It decreases the inflammatory process and helps minimize an over reaction of the immune system to foreign bodies or infections. Unfortunately, it also suppresses the immune system to the point that the body has a hard time mounting a proper response. The body is more susceptible to infections, especially those caused by bacteria. This is one of the reasons why we routinely prescribe antibiotics when we prescribe cortisone if we suspect any type of bacterial or fungal infection.

  • Mineralcorticoids

    Aldosterone is the principal mineralcorticoid secreted by the adrenal glands. This hormone is secreted as a response from the kidneys when fluid volume in the bloodstream is decreasing. It involves other hormones called renin and angiotensin. The end result is an increase in sodium in the bloodstream, with a corresponding increase in blood volume and blood pressure. This hormone also interacts with and affects potassium levels. To further complicate the picture, ACTH also has an affect here, just like it does with cortisol.

    This part of adrenal gland physiology is not significantly altered in Cushing’s. Addison’s disease, which is the production of too little cortisone, has a greater affect on aldosterone.

  • Epinephrine (Adrenaline)

    This compound, technically called a neurotransmitter, also has hormone-like properties. It is a very powerful chemical that effects all organ systems. It acts very rapidly, with effects remaining only for a short period of time. It is the primary reason the body has the ability to respond to an emergency. This physiologic mechanism is also known as the “flight or fight” response.

    Upon stimulation of the central nervous system (ex.-fear or pain), the adrenal medulla is stimulated to secrete epinephrine into the bloodstream. We are all familiar with what happens next. The pupils dilate, the heart rate and blood pressure increase, and the palms get sweaty. Internally, the body is increasing the blood glucose level, the breathing passages are opened up, more red blood cells are secreted into the circulation, blood is shunted away from the skin and other internal organs, and blood flow is increased to the brain and skeletal muscles. All of this has the effect of bringing the brain and skeletal muscles extra glucose and oxygen, and accounts for the extra boost of awareness and energy we all feel at this time.

Cause

Pituitary Dependent (PD)

Up to 85% of all Cushing’s cases in dogs fall into this category. The pituitary gland is invaded with a slow growing cancer called an adenoma. This causes it to secrete an excess amount of ACTH. The cells in the zona fasciculata area of the adrenal glands respond to this excess ACTH by hypertrophying (enlarging) and secreting excess cortisol. It is this excess of cortisol that is circulating in the bloodstream that causes the symptoms we see in this disease.

This pituitary gland tumor can remain slow growing and not effect the pet any more than inducing Cushing’s disease. In 10-20% of these tumors they enlarge to the point that they will cause significant neurologic symptoms. Unfortunately, some of these neurologic symptoms mimic those seen as side effects to the medication used to treat Cushing’s.

Brain tumors are best diagnosed using an MRI (magnetic resonance imaging). This boxer has a large white tumor in its brain.

Non-Pituitary Dependent (AT)

In up to 15% percent of Cushing’s there is an actual tumor of one of the adrenal glands (sometimes both are involved). The tumor enlarges and secretes excess cortisol in the bloodstream. This excess cortisol is monitored by the hypothalamus and pituitary in the negative feedback mechanism, causing them to secrete less ACTH. Less ACTH in the bloodstream will cause the other adrenal (if it does not also have a tumor) to atrophy (shrink).

The benign version of this tumor occurs 50% of the time, and is called an adenoma. These dogs usually live a normal life. There is a small chance this adenoma can progress to a macroadenoma, where the prognosis is not as good.

The malignant version, which occurs the other 50% of the time, is called an adenocarcinoma. It can invade the primary vein returning blood back to the heart (called the vena cava), and spread from the adrenal gland to the liver, lung, kidney, and lymph nodes. Dogs with adenocarcinoma usually do not live more than a year.

Ferret-AdrenalNormalRIghtVC

The white arrow points to a small and normal right adrenal gland in a ferret. A lobe of the liver has been pulled forward so you can see the adrenal gland. The dark blue structure running horizontally is the vena cava (VC)as it coarses past the liver towards the heart. The close proximity of the adrenal to the vena cava and liver shows how easily a malignant tumor here can spread into the bloodstream and lodge elsewhere in the body.

Ferret-LargeRtAdrenal6

This is a very large right adrenal tumor, almost as large (and intertwined) as the kidney below it. Notice how the vena cava (dark blue vertical structure to the right of the tumor) goes in a different direction that the pictures above. Removing it is not possible without also removing the vena cava.

 

This chest radiograph follows the vena cava (arrows) as it passes through the diaphragm and continues from the liver to the heart. Unfortunately, the heart unwittingly can now pump cancerous tissue to the rest of the body.

Adrenal tumors are a common problem in ferrets. The adrenal tumor in this case does not secrete excess cortisol, so technically the disease is not called Cushing’s. The tumor causes an excess secretion of sex hormones, causing a different set of symptoms when compared to the dog and cat.

Iatrogenic

Exogenous (external or supplemental) use of cortisone is very common in medicine. It is a highly beneficial drug used to treat a wide variety of diseases. In some cases it is used as an emergency drug to literally save a life. Cortisone is beneficial in several disease categories:

  • Inflammation
  • Immune system
  • Neoplasia (cancer)
  • Cerebral edema (brain swelling)
  • Shock

Long term use of cortisone, in oral, injectable, or even topical form, might cause an animal to have the symptoms of Cushing’s disease. It all depends on the type of cortisone used, the dose it is used at, and the duration of use. As a general rule, once the original symptoms of the disease are treated with cortisone, we recommend decreasing its use, stopping its use, or finding an alternative drug. Sometimes this is not feasible though, especially in immune system diseases. The symptoms of these diseases far outweigh the potential side effects from this exogenous use of cortisone.

The level of cortisone that results from this exogenous use will cause the adrenal glands to atrophy. The negative feedback loop tells the brain there is plenty of cortisol in the bloodstream, so the pituitary secretes less ACTH. The pet has the symptoms of Cushing’s because cortisone is being introduced into its body, not because the adrenal glands are producing it in excess amounts.

Exogenous cortisone goes by several names. They come in injectable, oral, and topical forms, and tend to be more potent than the cortisol that is naturally produced by the adrenal glands. Some of the more common ones are:

 

 

Ectopic ACTH Syndrome

This is a rare version of Cushing’s that does not fall into any of the above categories. It can be found in association with cancer in the dog.

Symptoms

Some dogs with Cushing’s disease show the classic symptoms, while other show only a few vague symptoms. The classic symptoms are:

  • Polyuria/polydipsia (PU/PD)- This is excess urinating and excess drinking of water. It is one of the first signs of the disease, and usually precedes the other symptoms by a significant period of time. Several other important diseases cause these symptoms also, notably liver disease, kidney disease pyometra, and diabetes mellitus (sugar diabetes).
  • Pot bellied abdomen to the point a dog might look pregnant. It is due to hepatomegaly and abdominal muscle weakness (the mechanism of which was described above in the physiology section).
  • Thin skin and usually symmetrical hair loss along the trunk. The hair might grow in lighter in color or lose its luster. It might not grow in well at all. Calcium deposits under the skin, called calcinosis cutis, occur on occasion. Secondary skin infections called pyoderma are common also. The skin might also be hyperpigmented.
  • Muscle wasting over the head, shoulders, thighs, and pelvis.
  • Polyphagia- excess appetite. This is often interpreted by clients as being healthy, since most people think of a sick pet as not eating well. In this case your pet is over-eating, which is consistent with Cushing’s.
  • Other occasional symptoms include:
    • Pruritis (itchy skin)- due to secondary bacterial, fungal, or parasitic infections of the skin
    • Panting- due to affects on the lungs or the respiratory center in the brain
    • Obesity
    • Anorexia (poor appetite)
    • Straining to urinate or blood in urine due to urinary tract infection or bladder stone
    • Weakness
    • Depression
    • Aggression
    • Lethargy
    • Corneal plaques
    • Irregular heat cycles in female dogs
    • Testicular atrophy in males and clitoral enlargement in females
    • Emesis (vomiting) due to pancreatitis
    • Ataxia (incoordination), blindness, circling, and seizures due to a large pituitary tumor or spread of a malignant adrenal tumor
    • Lameness due to a ruptured cruciate ligament
    • Intra-abdominal bleeding near the kidneys (retroperitoneal space) resulting in anemia, weakness, and abdominal pain

Diagnosis

thorough approach is needed for a correct diagnosis of Cushing’s. In every disease we encounter we follow the tenet’s of the diagnostic approach to ensure that we make an accurate diagnosis, and also so that we do not overlook some of the other diseases that are common in pets as they age. Nature works in complex ways, and just because you have one disease does not mean you cannot get another one to complicate the matter.

The best way to diagnose this disease is with history and physical exam. If your dog has PU/PD, polyphagia, alopecia, muscle weakness, and excessive panting, then it most likely has Cushing’s. The adrenal screening tests are used to verify the diagnosis.

Some dogs have the normal symptoms of Cushing’s, but routine blood sampling does not bear this out. In these cases we will repeat the adrenal screening tests at some time in the future or even abdominal ultrasound to look at the actual glands.

1. Signalment

Cushing’s tends to be a problem that affects older dogs, usually greater than 6 years of age, with a median age of onset at around 10 years. The disease tends to have a slow and gradual onset, so the early symptoms are easily missed.

Several canine breeds are prone to getting Cushing’s:

Females and males get it at about the same frequency.  Neutered pets might be at higher risk of Cushing’s.

2. History

Cushing’s disease is suspected in any pet that has some of the symptoms described above, particularly the skin symptoms and the PU/PD. It is important to remember that some dogs do not show any symptoms early in the course of the disease. This is another reason for yearly exams and blood and urine samples in dogs and cats 8 years of age or more.

Since dogs with this disease do not have a poor appetite usually (they have the opposite as explained in the symptoms section above), owners will delay in bringing their dog in for an exam. They assume a good appetite means their dog is doing fine. They misinterpret the excessive appetite (polyphagia) as being a good sign, when in reality its a sign of disease.

Most people wait until a dog, that is normally housebroken, is now urinating in the house. This delay can make it difficult to treat, and will frustrate some people to the point they are contemplating euthanasia.

Other historical findings include skin infections that recur after antibiotic therapy is stopped. Some dogs have a history of pruritis (itchiness) if pyoderma is present.

A history of poorly controlled diabetes mellitus might also clue us in to Cushing’s.

3. Physical Exam

Routine physical exam findings might include:

    • Pot bellied abdomen
The abdomen of this dachshund is pot bellied due to Cushing’s. It could also have been due to fluid buildup from cancer or heart disease. An enlarged liver from a disease other than Cushing’s can cause this also.
    • Enlarged lymph nodes due to secondary bacterial infections or spread of an adrenal tumor.
    • An enlarged liver (hepatomegaly) might be palpated, along with smaller muscle mass (atrophy) in general.
    • Bruising (hematoma) might be observed under the skin, or when a blood sample is obtained.
    • Skin infections and wounds that do not heal or recur after antibiotics are stopped.
This dog has hair loss with a secondary skin infection called pyoderma
  • Hair loss (alopecia) that is symmetrical, along with thin skin, poor hair coat, and calcium deposits under the skin. Many skin conditions have similar symptoms, so numerous diseases have to be kept in mind. They include hypothyroidismskin allergiessarcoptic mangedemodectic mange, andRingworm.
  • Blood pressure might be elevated. This might cause a detached retina, picked up by an ophthalmic exam.
  • Heart disease, initially noted with the stethoscope as an increased heart rate, an irregular heart rate, or a murmur.

4. Diagnostic Tests

Several tests are used as an aid in making this diagnosis. Each test has its advantages and disadvantages.

  • Skin Scraping

    Skin scrapings are usually negative in Cushing’s, although demodex is possible as a secondary problem due to the immunosupression effect of cortisol. Long term use of cortisone orally can also predispose a pet to demodex due to its immunosuppressive effects.

  • Blood Panel

    A CBC (complete blood count) and biochemistry panel should be run on every dog 8 years of age or more, especially if they have any of the symptoms of Cushing’s.

    The CBC might show an increase in the number of red blood cells (RBC’s) and/or an increase in platelets (thrombocytosis). It might also show an increased WBC (white blood cell count), called leukocytosis. When these white blood cells are broken down, there are usually more neutrophils (neutrophilia), less lymphocytes (lymphopenia), and less eosinophils (eosinopenia). These white blood cell abnormalities can also be caused by the “stress response”. It is due to excess epinephrine and cortisol secreted in response to the actual process of taking the blood sample (those people that have passed out when their blood was taken are an extreme example of this). The excess cortisol secreted by the adrenals in the stress response is temporary, and part of normal physiology. It is not caused by Cushing’s disease.

    Cholesterol, blood glucose. triglycerides, and liver enzyme tests (ALT) might be elevated in Cushing’s. If a thyroid test is run it might be low or borderline normal.

    An elevated alkaline phosphatase (Alk Phos) is a consistent finding in Cushing’s. This is an enzyme that is located in the bile production area of the liver. The excess cortisol influences this enzyme, although growing animals, fractures, obstructions of the bile ducts, liver disease, drugs, pets with diabetes mellitus, and pets with cancer can all cause an elevated Alk Phos. A significantly increased Alk Phos alerts us to keep Cushing’s in our tentative diagnosis list.

    BloodPanel-AlkPhos

    This dog has a mildly elevated liver enzyme test and am elevated Alk Phos. If the signalment, history, and physical exam do not make us suspect Cushing’s we probably will not proceed to adrenal screening tests. This dog should be examined, and the blood should be checked every 3-6 months to see if these abnormalities are increasing.

    Cushings-BloodPanelPreTrt

    This dog with Cushing’s has several problems on the blood panel that are secondary to the Cushing’s:

    Increased WBC- 23.7

    Severely increased liver enzymes- Alk Phos- 5224

    Low thyroid- <0.5

    Low urine Specific Gravity- 1.008

    Cushings-BloodPanel

    This is the blood panel on the same dog with Cushing’s two weeks after starting treatment. The WBC’s are back to normal, and the Alk Phos is much less. As time we goes on and we continue treatment we can expect these values to continue to improve.

     

  • Urinalysis

    A normal specific gravity in a dog should be at least 1.025, and there should be no or minimal protein, glucose, WBC’s, or bacteria, as a general rule. With Cushing’s, the specific gravity of the urine might be low, the protein might be elevated, and a urinary tract infection might be present because of excess glucose in the urine.

    Urinalylsis-LowSG

This urinalysis of this dog shows a low specific gravity, which is consistent with Cushing’s

  • Skin Biopsy

    This test can give us an idea that Cushing’s is the cause of a skin problem. Many of the changes that are noted microscopically when evaluating the biopsy are also seen in other diseases, so it is not specific for Cushing’s. In spite of this fact, skin biopsies give us a large amount of information in skin conditions.

Radiography

Radiography might be of value if the adrenal glands are calcified (happens in up to 50% of adrenal tumors), otherwise the adrenals do not show up on a radiograph. Hepatomegaly can be seen on the radiograph, along with problems associated with other diseases in pets this age, so a radiograph can be highly beneficial to help rule them out. Radiography might also show osteoporosis (poor bone density) and calcification of soft tissue, both of which could be due to excess cortisol.

In this lateral view (laying on its side) of the abdomen, the kidney (K) closest to the arrow is the right kidney. The arrow points to where the right adrenal gland is located, although it cannot be seen since it is not calcified. The whitish area between the K’s is normal, and is caused by the effect of the 2 kidneys as they overlap.

This is a VD (ventral-dorsal, or laying on its back) view of a dog. The left kidney (K) is labeled, and the arrow points to where the left adrenal gland is located. There is some calcification in this radiograph, but it is not at the adrenal gland. Can you see it?

The liver (L) might be enlarged (hepatomegaly), although this enlargement can be found in other diseases, especially liver cancer and diabetes mellitus

  • Ultrasound

    This test can be highly beneficial in this diagnosis. The adrenal glands can be measured, and their internal architecture (called parenchyma) can be analyzed. It is not feasible to visualize all of the distinct different zones of the adrenal gland though. Other internal organs are also checked, giving us a substantial amount of information from just one test. A common incidental finding when we do a routine ultrasound on a dog suspected of having Cushing’s is to find this pet also has IBD (Inflammatory Bowel Disease).

     

    Ultrasound-adrenal

    This is what the right adrenal gland looks like during an abdominal ultrasound

    Cushings-USReport

This is the report

Screening Tests

This is the most reliable way to confirm a diagnosis of Cushing’s disease. These tests evaluate the interactions that are occurring between the hypothalamus, the pituitary gland, and the adrenal gland. The interaction between these glands is known as the hypothalmic-pituitary-adrenal axis. The first goal is to determine if Cushing’s disease exists. The next step is to determine if it is pituitary dependent (PD) or non-pituitary dependent (an adrenal tumor- AT). You might want to go back to the Cause Section above for a review before proceeding further.

Testing this axis is not as easy as it sounds. The mammalian body is a dynamic system with thousands of chemical reactions and interactions occurring simultaneously. Also, levels of cortisol are in a continual state of flux, depending on the time of day, the season, medications, diet, and stress levels. Underlying diseases like Urinary Tract Infections can affect these screening tests, and need to be controlled first. Because of all this variability, interpreting these tests can be problematic, and it is not uncommon to repeat them in the future to look for consistent findings and monitor trends.

We prefer to perform these tests when the stress level (for example a car ride to our hospital) is not high. It might be worth it to take your dog for a short walk after you park the car to let it settle down. One of the rests requires a 8 hour hospital stay.

The normal values in animals calculated by a particular lab are called reference values. They reflect 95% of the population, statistically the same thing as the values that fall under the bell shaped curve. Not every animal falls perfectly into this range, so there is always a degree of interpretation needed in determining whether a value is abnormal or not. Eventually, it boils down to a determination of probabilities, coupled with experience in diagnosing diseases in animals.

Sometimes the test results are borderline for the disease. In these cases we use other test like ultrasounds, or we repeat the tests 1-3 month down the road.

Two important concepts of laboratory testing relate directly to Cushing’s:

Sensitivity

The sensitivity of a test refers to the ability of that test to detect diseased patients. A Cushing’s test that is 95% sensitive will diagnose Cushing’s in 95% of all dogs with Cushing’s disease. 5% of the dogs in this scenario will have Cushing’s, even though their screening test for Cushing’s says they don’t have the disease.

Specificity

The specificity of a test refers to the ability of the test to detect only diseased patients. A Cushing’s test that is 95% specific means that 95% of the time if the test is positive for Cushing’s, the animal really does have Cushing’s. This means that 5% of the time the test will say an animal has Cushing’s disease when in reality it does not.

Animals that do not have Cushing’s disease might show up positive on these tests, while others that have the disease might be negative on these tests. Many times we have to play the odds based on probabilities. Due to this limitation in testing we recommend using these tests in combination, and repeating them if they do not give clear cut answers.

These tests sometimes come back as positive for Cushing’s when in reality other diseases are affecting the cortisol level. Some of these diseases (called non adrenal illness) include liver disease, chronic kidney disease, urinary tract infection, skin diseases, and uncontrolled diabetes mellitus. Also, cortisone and anticonvulsants can give false positives.

The most common screening tests are as follows. Now might be a good time to take that bathroom break before reading about these tests.

Urine cortisol:creatine ratio

In this test the level of cortisol in the urine is measured and used as an indication of the cortisol level in the bloodstream. Creatinine is measured to adjust for different levels of urine dilution. Our kidney page has more information on creatinine.

This test is useful as a screening tool when our differential diagnosis (you know what that means because you read theDiagnostic Process page) does not put Cushing’s on the top of the list. For example, we might use it in a pet that has PU/PD, but not the other signs of Cushing’s. It works in both dogs and cats.

Urine-Cort-Creat

This one came back positive, which means this dog might have Cushing’s, and it warrants further testing to confirm. If it was negative, we would probably not do any further testing for Cushing’s, unless we felt the test was improperly obtained, or the dog had significant symptoms of Cushing’s.

This test is easy to perform because all that is needed is a urine sample. We recommend you obtain this sample at home in the morning just after your pet wakes up. Bring it to us immediately for analysis by our lab. Obtaining it at home will minimize the stress of a car ride and a visit to our hospital, both of which will normally increase the level of cortisol in the bloodstream (remember the stress response?), thus affecting this test.

A high level of cortisol in the sample is suggestive of Cushing’s. Unfortunately, up to 80% of dogs that don’t have Cushing’s will also have an increased level. This means that the specificity is low.  If the cortisol:creatinine test comes back normal, then it is unlikely that Cushing’s is present, and we do not routinely recommend the following screening tests. A cortisol:creatinine ratio test that is high means Cushing’s might be present, and needs one of the other screening tests to determine if Cushing’s is indeed present.

ACTH Stimulation

This test checks for Cushing’s and Addison’s Disease. We tend to use this screening test when we suspect Iatrogenic Cushing’s. It is also used to monitor therapy on pet that is on medication for Cushing’s and Addison’s disease.

When a dog or cat is given ACTH by an injection the adrenal glands are stimulated to produce cortisol. By measuring this cortisol with a blood sample we can determine what reserve the adrenal glands have in the production of cortisol.

ACTH

This is what we use for the ACTH stimulation test

This test is very specific for Cushing’s, so false positives are rare compared to other screening tests. It is not as sensitive as other screening tests, particularly the LDDS test.  20% of dogs that have Cushing’s will be negative on this test. For this reason it is sometimes used in combination with the LDDS test.

ACTHReport

This dog does not have Cushing’s according to this test, but it might also be a false negative if the symptoms of Cushing’s are present

This is the only test that can distinguish between iatrogenic and naturally occurring Cushing’s. It is the only test that gives reliable results for a dog that has been on cortisone recently. It does not distinguish between pituitary dependent (PD) and non-pituitary dependent (AT-adrenal tumor).

A blood sample is taken to measure the resting cortisol level before ACTH is given. Two hours after the ACTH injection is given a blood sample is taken again to measure the level of cortisol. This two hours gives the ACTH injection time to stimulate the adrenal glands to produce cortisol.

In the dog, if the second test of cortisol is much higher than the first, it is suggestive of Cushing’s 80-95% of the time. It does not necessarily tell us if it is PD or AT, because this exaggerated response will occur in 85% of PD Cushing’s, and also 50% of those with AT Cushing’s. This test is not as reliable in cats, only 51% of cats with Cushing’s will show an exaggerated response.

If there is a reduced level of cortisol on the second blood sample, then either the dog has Addison’s disease or iatrogenic Cushing’s. This reduced response also occurs in dogs that are receiving Mitotane or Ketaconazole therapy for Cushing’s.

Between 5% and 20% of dogs that have Cushing’s (either PD or AT) will not show the exaggerated response expected with this disease. If this test is normal or borderline in a dog we suspect Cushing’s in these dogs then the test should be repeated at a later date, or the LDDS test should be performed.

Low Dose Dexamethasone Suppression Test (LDDS)

This is probably the best test when the history, physical exam, and routine blood panel and urinalysis are consistent with Cushing’s. We also use it when we feel there is no chance of Iatrogenic Cushing’s. It might also help differentiate between PDH and AT, but that is better determined by the HDDS test (High Dose Dexamethasone Suppression test). It only works in dogs because cats get a significant number of false positives.

It is sensitive for Cushing’s, because 85% to 100% of the time it finds a Cushing’s disease that is present. This means it does not diagnose a pet that has Cushing’s disease up to 15% of the time.

Its specificity is low though, meaning it might come back as positive for Cushing’s between 44% and 73% of the time when the dog does not have Cushing’s. If we are not sure of the results because of this variability, we might also perform an ACTH stimulate test.

This dose of dexamethasone (which is a version of cortisone) suppresses the adrenal gland from producing cortisol in normal dogs, but not those with Cushing’s. It achieves this suppression by interfering with the negative feedback mechanism. The dexamethasone is monitored by the brain as an excess of cortisone in the bloodstream, so less ACTH is secreted, and therefore less cortisol is secreted by the adrenal gland.

In this test an injection of Dexamethasone is given and cortisol levels are measured at 4 hours and 8 hours after the injection. Like the ACTH stimulation test, a pre-injection blood sample is taken to measure the resting cortisol level.

Cushing's-LDDSTestResults

Here are the LDDS test results on a dog that we suspected of having Cushing’s. What is your diagnosis in this case? It’s the same dog that had the ultrasound above.

High Dose Dexamethasone Suppression Test

This test is not used as a routine screening test. It comes into play when a dog already has Cushing’s and you want to be certain that it is not that rare case that is an adrenal tumor.

The protocol for this test is similar to the LDDS test, except of course, a higher dose of dexamethasone is injected. A dog with an adrenal tumor does not suppress cortisol levels from the baseline sample.

Summary of Cushing’s Screening Tests

Urine cortisol:creatinine

In some dogs with Cushing’s the excess cortisol that circulates in the blood stream will spill over into the urine. If this test is positive then a dog might have Cushing’s. If it is negative, there is a good chance it does not have Cushing’s.

ACTH Stimulation

A positive on this test gives a reasonably good chance that a dog has Cushing’s. It will not catch all dogs with Cushing’s, so a dog with a negative test might still have the disease. In general, we use this test to monitor patients that are already being treated for Cushing’s or Addison’s.

LDDS

This test will catch most dogs that have the disease, and is the test of choice for Cushing’s on dogs that have symptoms.  A negative on this test means that most likely the dog does not have Cushing’s. A positive on this test indicates that a dog might have Cushing’s. It is the most popular adrenal screening test.

If a dog has symptoms that are typical of Cushing’s, but all of these tests come back negative, we recommend repeating these tests every 1-3 months to monitor.

5. Response to Therapy

One of the tenets of the diagnostic process is whether or not a treatment that is instituted actually corrects the problem. This usually applies to Cushing’s. You should note significantly less PU/PD, improved skin, and a more active pet if the treatment is successful.

Treatment

Before we discuss treatment we need to keep things in perspective. This is a chronic disease, and most dogs do not die from this disease. We tend to treat when the symptoms described previously are affecting a dog’s quality of life or are a major nuisance to a pet owner. We do not routinely treat just because the tests say your dog has Cushing’s- the symptoms of the disease need to be present also. It might be years before this dog shows signs, if any, of Cushing’s.

Dogs that have significant symptoms of Cushings’ that have been confirmed by screening tests need to be treated to prevent potentially serious diseases secondary to Cushing’s that include Diabetes Mellitus, Urinary Tract Infection (UTI), pancreatitis and High Blood Pressure (Hypertension).

Urine C & S Report

To know if there is a Urinary Tract Infection a culture of the urine must be performed. This dog is negative for a UTI

Treatment can be drawn out, and involves significant time and expense to monitor your pet after we treat it. Also, in some dogs, treatment can lead to side effects that are more serious than the symptoms of this disease. One of these side effects includes a rare death, so we do not undertake treatment of this disease lightly.

This disease tends to occur in older dogs that commonly have other problems. Some dogs die of other diseases before the symptoms of Cushing’s become a significant problem. Treating Cushing’s does not necessarily give your pet a longer life. The goal of therapy is to give your pet a better quality of life.

Underlying problems need identification and treatment. The biggest underlying, overlooked, and serious problem we commonly find in dog with Cushing’s is Dental Disease. If your dog is hypothyroid the problem needs to be corrected with supplemental soloxine. Internal organ problems like kidney disease and liver disease need treatment for a successful Cushing’s outcome. Urinary tract and skin infections need to be cleared up with the use of antibiotics, and underlying diabetes mellitus needs to be regulated with insulin.

Some dogs with large tumors of the pituitary gland might initially respond to medical therapy for pituitary dependent Cushing’s. The Cushing’s symptoms, especially neurologic, might recur as the tumor progresses.

Several different treatment modalities have been developed for Cushing’s. Some are for Pituitary Dependent Cushing’s, some are for Iatrogenic Cushing’s, and some are for adrenal tumors.

Pituitary Dependent (PD) Cushing’s:

Trilostane

This is the newest treatment for this disease, and the one we recommend in most cases. Trilostane is an inhibitor of an enzyme called 3-beta-hydroxysteroid dehydrogenase. This enzyme is involved in the production of several steroids including cortisol. Inhibiting this enzyme inhibits the production of cortisol.

Trilostane Box

It will be given daily for the rest of your dog’s life

It is usually given once per day, but in some dogs, especially those with Diabetes Mellitus, the Cushing’s symptoms might not diminish at the once daily dosing and the medication needs to be given twice per day (every 12 hours). It always needs to be given with food for proper absorption. Some dogs do not absorb this drug even when treated with food. In that case, another drug needs to be used.

When we use this drug to treat your dog’s Cushing’s we will also give you a detailed flow chart of what to look for at home and when to return for additional test and monitoring. The ACTH stimulation test is used for monitoring purposes. Do not fast your dog on the day we do this test, and give the Trilostane as you always do.

Cushing's-FlowChart

This flow chart is helpful to monitor the adequacy of adrenal suppression by Trilostane

If your dog does not respond to Trilostane, and the ACTH stimulation test indicates inadequate adrenal suppression, the dose or frequency of administration might need to be changed.

If you are using the compounded version of trilostane, and your dog is not responding, switch to the name brand of trilostane (Vetoryl from Dechra).

Mitotane (o,p’-DDD)

This drug has been used to treat this disease for 30 years, and is  know by the trade name of Lysodren. It selectively destroys the zona fasciculata and reticularis, effectively limiting the amount of cortisol that these areas of the adrenal gland can secrete. Pets that are on insulin for diabetes mellitus need to have their mitotane and insulin doses adjusted downwards. It should be administered with meals to enhance its absorption. This drug is first administered at a loading dose for 7-10 days.

Side effects are not uncommon:

  • lethargy
  • emesis (vomiting)
  • diarrhea
  • anorexia (poor appetite)
  • weakness
  • ataxia (in coordination)

Side effects are due to the cortisol level being reduced below normal levels. Even if the cortisol level does not go below normal levels, a rapid decrease in elevated cortisol levels to the normal range can still cause these symptoms.

You need to closely observe your pet when it is on mitotane for any of the above side effects. If they occur you are to immediately stop medicating and call us. We will already have given you prednisone pills to give at home if side effects are significant.

After 7-10 days of loading dose the cortisol levels are assessed with the ACTH stimulation test. Do not give your pet any supplemental cortisone on the day of testing. The pre and post cortisol levels should be normal. If they are, then we will continue to use mitotane at a weekly maintenance dose to prevent the problem from recurring again. Once your pet gets to this point it is rare to need any supplemental cortisone pills.

Two long term effects can occur while on mitotane maintenance therapy:

  1. The Mitotane can be so effective that the adrenal glands do not produce enough cortisol for normal physiology. This is called iatrogenic hypoadrenocorticism. In these dogs we stop all mitotane therapy and use supplemental prednisone. Sometimes this side effect is permanent, and your dog needs to be on supplemental prednisone the rest of its life.
  2. It is not uncommon for relapses of Cushing’s to occur within 12 months, even while on the maintenance therapy. These dogs are again given a loading dose of mitotane, then converted to maintenance dose when cortisol levels are normal.Both of these effects emphasize the need for continual monitoring of your pet. This means close observation at home and ACTH stimulation tests every 3-6 months.

This drug controls the symptoms of Cushing’s 80% of the time.

Ketaconazole

This is a drug routinely used to control fungal infections. It has a different mechanism of action than mitotane. It inhibits cortisol production in dogs and humanoids by preventing enzyme pathways from functioning properly. Ketaconazole works for PD and AT Cushing’s. It is not as common to use as the previous 2 drugs.

It needs to be given at a test dose initially to watch for anorexia or emesis. If tolerated well, a loading dose is given for 7-10 days. After an ACTH test to determine if the cortisol is in the normal range, the drug is given every 12 hours for the rest of the dogs life. This is a more expensive proposition than mitotane.

Surgery

Surgery to remove both adrenal glands can also be used. It is an involved endeavor performed at a specialized surgical hospital. Post operative complications are common, and these pets need lifetime prednisone replacement therapy. As a result, this treatment is not commonly utilized.

Radiation

Recurrence of the symptoms of PD Cushing’s after initiation of therapy might be an indication of a large pituitary tumor. MRI is recommended to identify this type of tumor. Radiation therapy is recommended to prevent further progression of symptoms. Unfortunately, there are very few specialty radiation centers that can perform this procedure.

Iatrogenic Cushing’s

This form of Cushing’s is the easiest to treat since we are not giving a medication but taking one away. In most cases the elimination of exogenous cortisone will return your pet to normal function, although this might take several months. Some of the skin changes might take longer, and may not even return completely to normal. In some cases we use a decreasing dose of supplemental prednisone for several weeks to give the adrenal glands time to resume normal production of cortisol.

Adrenal Tumor (AT)

The surgery to remove the cancerous adrenal gland is called an adrenalectomy. It is a specialized surgery that is not routinely performed. Post operative complications are common.

Because the remaining adrenal gland is atrophied the dog needs to be supplemented with prednisone until the gland returns to normal function. ACTH tests are done every few months to determine when the gland is functioning normally, which can take up to 12 months.

Adrenal tumors can also be treated with mitotane at high doses and for a long period of time. Side effects are common at this dose, and relapses can occur. These dogs will also need to be on supplemental prednisone for the rest of their lives.

Feline Cushing’s

Cushing’s in cats is rare compared to dogs. One reason is because they tend to be more resistant to higher levels of cortisol, especially if iatrogenic. Most feline Cushing’s occurs in females. It can affect the ability to control the blood sugar level in cats with diabetes mellitus concurrently.

History

Cats do not show as much PU/PD as dogs do, unless they have diabetes mellitus concurrently. Most cats are presented in a more advanced state of Cushing’s disease because the early symptom of PU/PD is not observed. They might also have hepatomegaly, weight gain, pot-bellied appearance, and muscle wasting. Sometimes the skin is easily bruised and torn. This is called the fragile skin syndrome.

This picture is from an older cat that was at the groomer to be clipped. The skin literally peeled off like wet tissue paper when the groomer attempted to clip some mats. This is a serious problem and does not lend itself to easy treatment.

Diagnosis

Cats do not routinely show any changes on a regular blood panel or urinalysis. The most consistent finding on a blood panel is hyperglycemia. An elevated alkaline phosphatase occurs in only a minority of cases. Oftentimes the elevated alkaline phosphatase is due to liver changes from unregulated diabetes mellitus.

The urine cortisol:creatine ratio test is helpful in cats, especially since it is a relatively stress free test compared to blood sampling. If the test is normal then there is much less of a chance that Cushing’s is present. It the test is elevated it might be Cushing’s, but there are also other situations that cause this elevation.

The ACTH stimulation test is used, but two blood samples need to be analyzed at 30 and 60 minutes, instead of the 1 sample at 2 hours for the dog. This is because the increase in cortisol is variable in the cat. False negatives are common. False positives occur in stressed cats or those with non adrenal illness.

The LDDS test is used but the dexamethasone that is injected needs to be given at a higher dose. This test, when used in conjunction with the ACTH stimulation test, is one of the best ways to diagnose Cushing’s in the cat.

The HDDS test to differentiate PD from AT has not been refined to the point that is of diagnostic value.

In general, results of these tests can be variable, and must be interpreted in conjunction with the history and clinical findings. In light of the fact that Cushing’s is uncommon in cats, these tests need careful interpretation.

If the above tests suggest Cushing’s then radiology can be helpful since up to 30% of feline adrenal tumors are mineralized. Other radiographic findings include hepatomegaly and obesity. Ultrasonic evidence of an enlarged adrenal gland (especially if unilateral) or changes in internal adrenal architecture is strong evidence of an adrenal tumor (AT).

Adrenal tumors occur in about 20% of feline Cushing’s. They can be malignant or benign.

Treatment

Medical therapy is generally unrewarding. Ketaconazole can be used, but the effects are variable, and side effects can occur. Mitotane might help, along with metyrapone. Metyrapone may be more helpful as a presurgical stabilization prior to surgery. Anipryl has not been used in cats.

Surgery is needed to remove one of the adrenal glands if the gland has a tumor, and both glands if the problem is PD. If both glands are removed the cat has to be on supplemental cortisone and mineralcorticoids for the rest of its life. Some cats with concurrent diabetes mellitus will no longer have the disease when their adrenal tumor is removed.

Unfortunately, cats with Cushing’s can be poor anesthetic risks due to diabetes mellitus and fragile skin. When this occurs we sometimes will use medical therapy to help control the problem and make our patient a better anesthetic risk.

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Kidney Disease (Chronic Kidney Disease) or Chronic Renal Failure

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One of the more common conditions encountered in pets, especially as they age, is kidney (renal) disease. This disease is particularly prevalent in cats, and is called chronic kidney disease (CKD). It is also known as chronic renal failure (CRF). Once a pet has CKD the changes in the kidney are irreversible, so it is important to catch this disease early to mitiage its progression.

Because of the prevalence of this probem in cats, and the fact it is incurable, all cats starting at 8 years of age should be fed a diet called Hill’s K/D Early Support. This will go a long way in helping prevent the onset of kidney disease in cats. We want to start this food long before your cat starts losing weight and before the kidney tests on the blood panel are showing a problem.

25% of the blood ejected from the heart on every heartbeat goes directly to the kidneys, a testimonial to how important the kidneys are to health. When a pet has chronic kidney disease there are many issues that need to be addressed for a successful outcome. You will learn about them in more detail later in this page. The more important ones are:

  • Protein and phosphorous regulation
  • XS protein in the urine
  • Elevated creatinine in the bloodstream
  • High blood pressure
  • Anemia
  • Dehydration and electrolyte imbalance
  • Low pH in the bloodstream
  • Stomach and intestinal ulcers
  • Body condition score

We use the IRIS (International Renal Interest Society) system of classification at the Long Beach Animal Hospital to better diagnose and treat CKD. IRIS is a group of veterinary kidney specialists throughout the world that have studied this disease extensively and have set standards for diagnosis and treatment. At the end of this page there is a link to this organization for more information on how they stage kidney disease.

The IRIS system stages kidney disease from Stage I to Stage 4. We want to catch those pets that are at Stage I so we can initiate treatment then, and have a much better outcome. If you start your cat on K/D early support you are already way ahead of the curve.

In this staging system we are closely monitoring several important parameters:

  1. Creatinine trends
  2. Protein in the urine
  3. Blood Pressure
  4. Body condition score

urinalysis-protein-cat

This cat has a normal creatine, so the kidneys seem OK on the blood panel. The urinalysis shows a protein level of 1+. This could be the sign of CKD in this cat, and should be treated early if further tests indicate it does have CKD. Just changing to a food like Hills K/D can make a big difference on a cat like this if started early in the course of the disease, and before other problems related to CKD appear. 

In addition to these parameters, the following general parameters are also checked for early signs of chronic kidney disease. These parameters are also used to monitor progression and success of treatment:

  1. Small kidneys on abdominal palpation
  2. Radiographic or ultrasound evidence of small kidneys
  3. Decreased urine specific gravity

This page describing kidney disease is very thorough with significant information on anatomy, physiology, and pathophysiology. How the kidneys regulate water consumption and urine production are controlled by complex and highly refined interactions between plasma osmolality, fluid volume in the bloodstream, the thirst center in the brain, the kidneys, the pituitary gland, and the hypothalamus. Even though this page is thorough, the physiology of the kidneys is complicated, and only a summary of how the kidneys work is prestented on this page.

We have information on treatment towards the end of this page if you want to bypass all the background information and skip right to it. We also have a summary page on kidney disease if this page is too detailed.

Pets that have kidney disease commonly have other problems that need careful attention if the kidney problem is to be treated successfully. Some of these other common problems are:

Hyperthyroidism

 Heart disease

Inflammatory Bowel Disease

 Dental disease

 Sugar diabetes (diabetes mellitus)

 High blood pressure (hypertension) – leading to blindness.

Several medical terms are used when describing kidney disease:


Renal anatomy

The kidneys are such a vital organ that 25% of the blood that enters the circulatory system from each heartbeat goes directly to the kidneys through the renal artery. With such a high metabolic rate the proper functioning of this organ is critical to health. The high metabolic rate and importance of this organ makes the kidneys susceptible to many problems.

The kidneys are located in a specific area of the abdomen called the retroperitoneum. This area is a small indentation at the top of the abdomen just underneath the spinal vertebrae. This location, in addition to being surrounded by a fat, affords added protection to this vital organ.

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The kidney is normally covered in a layer of fat

This is a kidney with surrounding fat removed. You can see the dark liver on the far left, and the renal vein as it leaves the kidney and mergers with the vena cava. The blood from the vena cava flows into the liver and then directly to the heart. This is the blood that has been filtered of impurities and is reentering the circulation. You can not see the renal artery or ureter, they are buried in the white fat at the top of the kidney.

Blood enters the renal artery and flows into the nephron where it is filtered. The blood from the renal artery that has been filtered now flows out of the renal vein where it goes back into the circulatory system. The impurities that the nephron filters out of the blood collect in the renal pelvis and eventually out into the ureter in the form of urine.

The primary functional unit of the kidney is the nephron. Each kidney has upwards of one million nephrons, so obviously they are microscopic in size. Every nephron is a self contained unit that can form urine by itself. Not all nephrons are used at the same time, which gives the kidneys the capacity to increase their workload if called upon. This reserve capacity is lost when chronic renal failure occurs. These pets (especially cats) outwardly appear normal, but have greatly reduced ability to adapt to changing physiologic needs. Being chased by a dog, not having enough water to drink, etc., can send them into a crisis, requiring immediate medical care.

This is the cut section of an actual  kidney from a cat

This is a kidney, turned partially to the right sideways to the one above, as we view it with the ultrasound. The yellow line is measuring its length.

The important anatomical components of the nephron are described below:

  • Afferent Arteriole

    This small artery is one of the many small branches that come off the renal artery as it enters the kidney. It supplies the glomerulus with blood. Eventually filtered blood returns to the renal vein.

  • Glomerulus

    This is a collection of many small blood vessels at the end of the afferent arteriole. Normal pressure of the blood in the glomerulus causes fluid to flow into a collecting area called Bowman’s capsule.

  • Bowman’s Capsule

    Fluid that collects in Bowman’s Capsule eventually flows into the tubules. It is in these tubules that waste products and excess electrolytes are filtered out of the fluid, and normal blood constituents like protein and glucose are absorbed back into the bloodstream. When a diuretic like Lasix is given it acts on these structures.

  • Collecting Ducts

    At the end of the tubules is the collecting duct, where the urine produced starts to flow out of the nephron. Other nephrons deposit urine in collecting ducts as these ducts flow into the renal pelvis. From the pelvis the urine flows into the ureter and bladder.

Renal Physiology

The kidneys have a profound affect on almost all the physiologic processes of the body. The mechanism by which the kidneys perform these functions is extremely complex, the most important of which will be summarized:

  • Fluid Regulation

    In relation to the kidneys, the brain monitors bloodstream levels of water, waste products, electrolytes, and red blood cells. The circulatory system also has receptors like the brain to monitor blood volume also. If the water level is too low, as occurs with dehydration, the brain secretes more of a hormone, called ADH (anti-diuretic hormone), into the bloodstream.

    As a result, the kidneys excrete less water into the urinary tract, retaining more fluid in the bloodstream to counteract the dehydration. The brain also increases thirst simultaneously. The end result is less urination. The urine that does get excreted is more yellow than usual due to a greater concentration of waste products being excreted in relation to the amount of water being excreted. The only thing we notice is that we urinate less and it is more yellow in color.

    As we drink water to quench our thirst and rehydrate, the body notes this change and the brain secretes less of the hormone called ADH. Now when we urinate more water is excreted by the kidneys, and our urination occurs with a dilute urine in greater quantity. So, the ability to concentrate the urine and dilute the urine is an important function of the kidneys. It is a fine tuned mechanism that is closely regulated to maintain optimum amounts of fluid in the bloodstream and organs.

    As a fun fact, it is the inhibition of ADH by alcohol’s depression effects on the brain that causes excess urination when drinking alcoholic beverages. Eventually this excess urination causes dehydration, leading to that inevitable curse called a hangover.

    The kidneys also secrete a hormone called renin. Through a complicated set of biochemical pathways this ultimately leads to an increase in salt (sodium) in the bloodstream. Sodium pulls water towards it, so more sodium means more fluid in the bloodstream. It will have an effect on blood pressure, which you will learn about later.

  • Waste Product Regulation

    The brain also monitors waste products that build up in the bloodstream. These waste products are the end product of normal metabolic processes, especially the metabolism of proteins. They are called nitrogenous waste products, and are measured by a blood parameter called blood urea nitrogen (BUN). Another waste product that is closely regulated by the brain and kidneys is called creatinine. It is the end product of the metabolism of muscle.

    The kidneys also excrete toxins and foreign substances that are introduced into the body. Almost every medication given, either orally or by injection, is eliminated to some degree by the kidneys.

    The rate at which fluid flows into the glomerulus is important. This is called the glomerular filtration rate (GFR), and is measured in ml/minute. Too small a flow and waste products are not eliminated, a problem encountered during dehydration. Too much flow and normal blood constituents like protein are excreted when they shouldn’t be.

  • Electrolyte Regulation

    Electrolytes are also of importance in relation to the kidneys. Sodium is of extreme importance in the normal functioning of all cells. It allows nerve impulses to occur and is critical in the regulation of water levels in the bloodstream. Through the release of a hormone called angiotensin the kidneys regulate fluids levels of sodium in the bloodstream. This has a major affect on the blood pressure. Potassium is also a critical electrolyte. Potassium levels need to be kept at a very narrow range to prevent serious consequences like heart irregularities.

  • Hormone Regulation

    The kidneys also regulate calcium and phosphorous by hormones called calcitrol and parathyroid hormone, and by regulating vitamin D. Vitamin D allows the absorption of calcium from the intestines. If the kidney disease progresses long enough the excess secretion of parathyroid hormone causes the bones to become swollen and fibrous as the body attempts to maintain a normal calcium level. This is called renal osteodystrophy.

    As the bones become more fibrous the marrow is not able to produce red blood cells as effectively. This leads to weak and thin bones, as evidenced by a swollen face and jaw as the bones of the lower jaw weaken. It can occur in other bones also. This is similar to what occurs in reptiles when they get bone disease. You can see a picture of the swollen jaw of an Iguana with bone disease. Don’t forget to come back here because we are only just getting going.

  • Acid-base Regulation

    The pH of the bloodstream, which is a measure of acidity, is another important area of kidney physiology. The kidney regulates this acidity by excreting excessive hydrogen ions and the selective secretion and reabsorption of bicarbonate.

  • Red Blood Cell Production

    The kidneys secrete a hormone called erythropoeitin into the bloodstream. This hormone circulates to the bone marrow and stimulates it to produce red blood cells. A lack of adequate levels of this hormone will cause anemia. Toxic waste products that build up in the bloodstream decrease the life span of a typical red blood cell, further exacerbating the anemia. And, as you already learned above in hormone regulation, the fibrous bones have less bone marrow. There can even be clotting problems due to a low number of platelets.

Pathophysiology of Chronic Renal Failure

Over the course of days, weeks, or months, normal nephrons get replaced with scar tissue, and become nonfunctional. In chronic kidney disease (CKD) this scar tissue is a result of excess phosphorous. When this scar tissue occurs to approximately 75% of the nephrons the kidneys no longer have the ability to respond to the needs of the body. There is no longer any reserve, and all of the remaining nephrons are working full time. These remaining nephrons swell (called hypertrophy) to adapt to this increased workload. This allows them to adapt and selectively excrete or reabsorb important nutrients.

Eventually these remaining nephrons cannot keep up, and it leads to a buildup of nitrogenous waste products (called azotemia) in the bloodstream. The body compensates by increasing thirst, which causes PU/PD, and the waste products get flushed out of the bloodstream and into the urine.

Unfortunately, flushing out the waste products in bloodstream with excess thirst also flushes out important electrolytes and protein into the urine. This causes weight loss and weakness as the kidneys continue to deteriorate. The excess urination that occurs as the body tries to rid itself of these excess waste products can also cause dehydration.

Oral ulcers occur when bacteria in the mouth convert the extra uremic waste products to ammonia. Waste products that buildup in the bloodstream also have an effect on the bacteria in the mouth and exacerbate gingival and periodontal disease. The waste products also change the pH of the bloodstream and cause ulcers in the stomach and intestines. This causes vomiting (emesis), loss of appetite (anorexia) and weight loss. Ulcers can also be found in the mouth and tongue due to the uremia.

Hormones are affected and phosphorous builds up in the bloodstream further adding to a pet’s woes. Eventually calcium is deposited in abnormal places, and can lead to problems with many skeletal and internal organ problems. Due to sodium imbalance, hypertension (high blood pressure) can develop. Hypertension occurs in a high percentage of animals with kidney disease.

As the kidneys continue to deteriorate erythropoetin is not secreted in adequate quantity and anemia results. This anemia also makes a pet weak and adds to the anorexia that is usually present.

The nervous system is affected by all of these problems. If the uremia is severe enough hypothermia and seizures can result.

Classification

  • Acute Renal Failure (ARF)

    This is a serious form of kidney disease that commonly leads to death. The kidneys have an abrupt decrease in the GFR due to a toxin or loss of adequate blood supply (called ischemia). Many different disease processes can cause ARF, including anesthesia for any surgical procedure. That is why we give intravenous fluids (IV) to almost every surgical case.

  • Chronic Renal Failure (CRF)

    This is the most common form of kidney disease we encounter, particularly in older cats. It tends to develop more slowly than ARF, so the body has time to institute corrective factors (called homeostasis) to compensate for the problem. Unfortunately, these corrective factors tend to hide early symptoms of disease. Consequently, treatment is not initiated as soon as it might be. Again, as in many diseases we encounter, this drives home the fact that pets over 8 years of age should have annual physical exams along with blood and urine samples.

    Pets in CRF that have lost their ability to compensate for their failing kidneys can be presented to us in an acute phase, similar to ARF.

Cause

The are a multitude of causes to kidney disease. Some of these cause ARF, while others cause CRF. In some cases, ARF can progress to CRF.

Toxins

Many drugs that are used on a day to day basis can be toxic to the kidneys:

  • snake and bee venom
  • antifreeze
  • pesticides
  • herbicides
  • solvents
  • heavy metals
  • cancer chemotherapeutic agents
  • aspirin and antinflammatories
  • anesthetics
  • anti parasite drugs
  • antibiotics
  • blood pressure medication

The outcome of exposure to these toxins depends on a pet’s age, other disease processes that might be present, any medication your pet is currently taking, how long there has been an exposure and at what dose, along with the specific toxin. In some cases they are treated with supportive care like intravenous (IV) fluids. Other cases are treated with specific antidotes.

Some toxins, notably antifreeze ( 95% ethylene glycol) are catastrophic to the kidneys. Antifreeze is very sweet tasting and is readily licked by both dogs and cats if it spills on the ground when car antifreeze is changed. Ethylene glycol is converted in the liver and kidney to a toxic metabolite that changes the pH of the bloodstream and destroys the kidneys by depositing calcium oxalate crystals in the renal tubules.

It is a medical emergency and requires specific and immediate measures if the kidneys are to be saved. Unfortunately, unless a pet owner actually observes their pet licking antifreeze, they don’t bring their pet in for care until it is very ill. In this situation the prognosis is grave, and death is common. If treated within a few hours of ingestion the prognosis for recovery is much better.

Antifreeze has several distinct phases:

Stage I

This occurs during the first 12 hours after ingestion. Pets will vomit, drink and urinate excessively (PU/PD), and appear intoxicated. It is at this stage that observant owners might bring their pet in for an exam.

Stage II

This stage occurs 12-24 hours after ingestion. Symptoms are vague and pets appear to recover.

Stage III

This stage appears 24-72 hours after ingestion. Pets in this stage are severely depressed, are not eating, are vomiting, and are not producing urine. When this stage appears death is imminent.

Treatment needs to be given early in the disease to be effective. Inducing vomiting and flushing the stomach out can be very helpful if performed within 1-2 hours of ingestion of antifreeze.

Intravenous fluids and diuretics are also given to maintain normal kidney function by keeping an adequate GFR. Sodium bicarbonate is given to maintain a proper pH of the bloodstream.

Antidotes are given and can be highly effective if given early enough. In cats we give them ethyl alcohol (vodka) intravenously, and literally make them drunk. The vodka prevents the liver from converting the ethylene glycol to the toxic metabolites that destroy the renal tubules. This treatment is used in dogs also.

A better antidote, that works in dogs only, is called Antizol. It is an expensive medication, but it can literally save your dogs life.

Fortunately, the antifreeze manufacturers have added a bitter taste and we do not see this disease anywhere near as commonly.

Cancer

Cancer of the kidneys can occur even at a young age, although it is usually diagnosed in older pets. Sometimes it arises from the kidneys (primary), much more often the cancer has spread to the kidneys from a different organ (secondary or metastatic). When primary cancer does occur it is often malignant. Fortunately, primary renal tumors are rare. Cancer of the kidneys occurs more in cats than in dogs. Click here to see a case study of how we diagnosed and treated kidney cancer in a dog.

Primary

  • Lymphosarcoma- Tthis is the most common renal tumor in the cat. Cats with renal lymphoma are commonly positive for the FeLV.
  • Adenocarcinoma- The next most common renal tumor in the cat
  • Transitional cell carcinoma
  • Nephroblastoma
  • Adenoma
  • Fibroma

Secondary

Poor Perfusion

Poor perfusion means inadequate flow of blood through the kidneys, which decreases the GFR. This lack of blood flow prevents the kidneys from eliminating waste products and toxins buildup in the bloodstream. This lack of perfusion is the main pathology leading to ARF.

Heart Disease – If the heart is weak it can not pump enough blood to the kidneys to keep them properly perfused.

Drugs – Some medications can cause constriction of the artery to each kidney with a resulting lack of perfusion

Dehydration – Inadequate fluid in the circulatory system will cause poor perfusion. Dehydration is the most common cause of poor perfusion.

Cysts

They can put pressure on normal kidney tissue and compromise the filtering ability of the nephron. These tend to be found in older male cats. When there are no symptoms they are sometimes found accidentally when checking for other problems. This is called an incidental finding. When symptoms are present, they can be mild and treated easily by drainage, or there might be compromise with the normal filtering ability of the kidneys.

A specific form of cyst, called Polycystic Kidney Disease (PKD), is inherited in Persian and other long haired cats. Cysts will occur in both kidneys and will lead to CRF eventually as they enlarge and decrease functional renal tissue. The best way to make this diagnosis is with ultrasound. Ultrasound should be used on the offspring of adult cats with PKD and before any symptoms appear.

Immune System Diseases

Bacteria, viruses, cancer, and diseases of internal organs can all set off a reaction where the immune system can interfere with the ability of the kidneys to filter properly. This is sometimes called glomerulonephritis. Symptoms range from mild early in the disease to all the signs associated with kidney failure. A common method of diagnosis is excess protein in the urine (proteinuria) and a lack of protein in the bloodstream (hypoalbuminemia).We use ultrasound at our hospital to help in this diagnosis.

Treatment depends on the exact cause. It might include anti-immune system drugs, aspirin, dietary change, medication to decrease blood pressure, salt reduction, IV fluids, and diuretics.

Parasites

There are 3 main parasites that invade the urinary tract and affect the kidneys:

    1. Capillaria plica

      They are threadlike worms that affect the kidneys, bladder, and urethra. Eggs of this worm that are passed in the urine are eaten by earthworms, which are then eaten by dogs to complete the cycle. In some dogs there are no symptoms, while in others there might be blood in the urine (hematuria), difficult urinating (dysuria), or urinating small amounts (pollakuria). This parasite is diagnosed by finding the egg in a urine sample. In most cases the disease goes away by itself within 4 months, although it can be treated. Prevention of recurring cases relies upon removal of surfaces that could harbor earthworms.

    2. Capillaria feliscati

      This is an uncommon parasite in our area that invades the urinary bladder of cats. Usually there are no symptoms, and the disease routinely resolves by itself within 4 months.

3. Dioctophyma renale

This parasite resides in the kidney or abdomen near the kidneys, although they have been found in the urinary bladder, urethra, ovary, uterus, and pericardium. It causes a gradual deterioration of the kidneys.Eggs from this parasite are passed through the urine and eaten by aquatic annelids. Dogs get this parasite from eating raw fish and frogs that have eaten the aquatic annelids.Sometimes there are no symptoms until there has been significant kidney destruction. They are diagnosed by finding the egg of the parasite in abdominal fluid or in the urine. Treatment involves surgical removal of the worms from the kidneys or abdomen.They are difficult to control because the eggs can live in the environment for a long time. Dogs should be prevented from eating frogs and raw fish. It is possible for humans to get this disease from eating raw fish or frogs also.

Viruses

The FeLV and FIP can affect the kidneys. These viruses are prevalent in the cat world, and cause significant problems. We do not see these diseases commonly any more, especially FeLV. This is a testament to the use of vaccines.

Bacteria

They can ascend from the lower urinary tract and cause dysfunction in the kidneys. Leptospirosis is a specific bacteria that affects the kidneys, seen almost exclusively in dogs. Dogs get it by direct contact with infected urine through their mucous membranes. It also affects the liver.

In severe cases a dog can go into shock and rapidly die from Leptospirosis. In some cases they are sick with a fever, depression, vomiting, diarrhea, and poor appetite. There might also be muscle pain, eye problems, and respiratory problems. Most cases are chronic and might not show many symptoms.

There is a vaccine to prevent this disease which is a routine part of our DHLPP vaccine. The vaccine is highly effective in preventing this disease.

Bacteria can also cause pyelonephritis, an infection of the renal pelvis. The following bacteria are implicated:

  • E. coli
  • Staph. aureus
  • Proteus mirabalis
  • Strep. spp.
  • Klebsiella pneumonia
  • Psuedomonas aeruginosa
  • Enterobacter spp.

These bacteria usually ascend from the lower urinary tract. Occasionally they enter the kidney from the bloodstream. Their presence can cause constriction of the blood supply to the kidneys and destroy normal kidney tissue when attacked by the immune system. They can eventually lead to kidney failure. It is important to culture the urine for bacteria in any pet that is diagnosed with CKD because of the damage these bacteria can do to the urinary tract.

These bacteria can cause ARF or CRF. Symptoms include fever, depression, lack of appetite, pain, PU/PD, and weight loss. In the chronic version sometimes there are no symptoms at all. They are treated with antibiotics for a minimum of 4 weeks, along with supportive care.

Amyloid

This is the deposition of fibrous protein cells in the glomerulus that interfere with the kidneys’ ability to filter. Amyloid causes the kidneys to become small and irregular. Pets with amyloidosis have typical symptoms of kidney disease.

Most dogs are middle aged or older, and it is seen in abyssinian cats and Shar Pei dogs. It is diagnosed by proteinuria, just like the immune system diseases that affect the kidney. Amyloid can be deposited slowly allowing a long life, or it can occur rapidly leading to early death. There is no specific treatment except routine supportive care of the kidneys.

Trauma

One of the more common causes of kidney trauma is when a pet is hit by a car. These injuries can be serious and easily lead to death. Radiography is helpful in making this diagnosis, although special x-rays or ultrasound might be needed to know for sure.

This is a bruised kidney from a cat that was attacked by a dog. The bruise covers over 1/3 of the kidney. This is a fatal lesion.

Symptoms

The symptoms that occur depend mainly on how long the problem has been present and the specific reason the kidney failed in the first place. Some of the more common ones you might notice at home are:

  • Excess urinating and drinking

    This is known as polyuria/polydypsia (abbreviated PU/PD). It is by far the most consistent symptom of kidney disease. PU/PD also occurs in sugar diabetes and hyperthyroidism to name a few, so the diagnostic process needs to be followed to make an accurate diagnosis of a pet with symptoms of PU/PD. If you suspect your pet of having PU/PD you should measure how much water it drinks each day and look for a changing trend.

    In ARF there might not be any urination (called anuria) at all. This is an extreme emergency. Two of the more common causes are antifreeze poisoning and male cats with urinary tract disease that have a plugged urethra.

  • Weight loss

    Weight loss occurs due to poor appetite and the loss of protein as the kidneys attempt to flush toxins out of the body.

  • Poor appetite (anorexia)

    The buildup of toxins, electrolyte imbalances, dehydration, and even anemia are the causes of a poor appetite in kidney disease. This is one of the most common reasons pet owners bring their cats to us when renal failure is the cause. Ulcers in the mouth and stomach add to this problem. Sometimes its a wonder that cats with moderate to severe kidney disease even eat at all.

  • Weakness

    Dehydration and poor appetite add to weakness. An imbalance of a specific electrolyte called potassium adds significantly to weakness. This is the reason we sometimes add supplemental potassium to the fluids we give pets with kidney disease and also why we supplement them with oral potassium.

  • Vomiting (emesis)

    The buildup of toxins is a big cause of the vomiting. Vomiting causes further dehydration and loss of potassium, further exacerbating the problem in pets with kidney disease.

  • Seizures

    If uremia is severe enough the brain can be affected by the toxins that build up.

  • Ulcers

    If the waste products are not being eliminated adequately the buildup of toxins can cause ulceration. These ulcers are prevalent in the digestive system, especially the stomach, and might necessitate medication.

    The tip of the tongue of this cat has an ulceration due to kidney disease. Oral ulcers are due to the breakdown of urea present in saliva to ammonia by bacteria found in the mouth. There are other causes of ulceration, including trauma, biting electrical cords, poisons, and viruses.

Blindness can occur due to the high blood pressure (hypertension) that develops as a consequence of CRF. We start therapy in cats when the systolic blood pressure consistently exceeds 160 mm Hg. Diastolic blood pressure is of no clinical use in the cat.

It can be difficult to get a consistent blood pressure reading in cats due to their stressful nature at our hospital. We will repeat the test numerous times, in a calm and quite environment, to make sure the readings are accurate.

The dilated pupils from this 15 year old cat with CRF are due to blindness

Checking a cat for high blood pressure (called Hypertension) is not as simple as in a human. Specialized equipment is needed.

Diagnosis

Since the symptoms of kidney disease mimic the symptoms of other diseases a thorough approach is needed to differentiate them. In every disease we encounter we follow the tenet’s of the diagnostic approach to ensure that we make an accurate diagnosis,  and also so that we do not overlook some of the other diseases that are also encountered in pets that have renal disease. Unfortunately, it is difficult to diagnose acute renal failure early in the course of disease.

Signalment

Kidney disease can occur at any age. If it occurs at a young age we tend to think more of toxins, cysts, and trauma. The most common form of kidney disease, CRF, occurs mostly in older pets.

Several feline breeds are prone to getting CRF as they age:

  • Siamese
  • Persian
  • Abyssinian
  • Burmese
  • Maine Coon
  • Russian Blue

Certain canine breeds are also prone to CRF:

History

Kidney disease is suspected in any pet that has some of the symptoms described above, especially PU/PD. The recent administration of medication, a recent bout of a disease, the changing of antifreeze, especially in the fall , and recent administration of anesthesia, are all helpful clues. Pets that have other diseases that can affect the kidneys, notably heart disease, and hyperthyroidism, alert us to the potential for kidney disease.

Physical Exam

Symptoms noted during a physical exam depend on what caused the kidney’s to fail, how long the disease process has been present and whether a pet has the acute form or chronic form of the disease.

Physical exam findings might include:

  • Pale gums due to anemia. You can check for pale games at home. Our Learning Center shows you how.
  • Dehydration
  • Small and irregular kidneys upon abdominal palpation if CRF is present
  • Large or nodular kidneys if a cyst or cancer is present
  • Underweight
  • Enlarged lymph nodes
  • Dilated or uneven pupils
  • Weakness

This older cat has kidney disease causing low potassium (hypokelemia). If the low potassium is severe enough a cat might have this neck posture.

Diagnostic Tests

Kidney disease can only be diagnosed with appropriate tests. As a general rule, we recommend screening for kidney disease by running a blood panel and a urinalysis on all pets greater than 8 years of age. We also screen for other diseases, notably liver disease, sugar diabetes, and hyperthyroidism, on this blood panel due to their prevalence in older pets.

Lymph node biopsy

Peripheral lymph nodes can be palpated in numerous locations. They can enlarge for several reasons, one of the more important ones is cancer. If they are enlarged and significant disease process is suspected then one of them is biopsied (example to follow).

Blood Panel

An important tool in the diagnosis of kidney disease is a blood panel. We look for abnormalities in several specific tests:

CBC- Complete Blood Count

This test checks the red and white blood cells. It is not uncommon for a pet with chronic kidney disease to have anemia.

The kidneys produce a hormone called erythropoeitin that stimulates the bone marrow to produce red blood cells. Anemia occurs in kidney disease due to inadequate levels of erythropoietin, shortened survival time of red blood cells in general, bleeding in the stomach or intestines, and the effects of uremic toxins on parathyroid hormone. Pets that are dehydrated might not show anemia on a blood sample until they are rehydrated.

This dog has white gums in addition to the severe dental disease that is present. The white gums are due to anemia from CRF.

Ferret-AnemiaBloodPanel

Anemia is noted in this pet by the low HGB (Hemoglobin) and low HCT (Hematocrit). This is mild, and might be correctable at this point.

This cat has a severe anemia, and needs a blood transfusion if it is too survive

BCP (Biochemistry Panel)

There are many tests on a BCP, the following are the ones that relate to kidney disease.

BUN (Blood Urea Nitrogen)

The BUN is usually elevated in pets with kidney disease. It can also elevate in dehydrated pets and in pets with an obstructed urethra causing an inability to urinate. If a urinary obstruction is the cause of an elevated BUN, called post renal uremia, the BUN levels tend to be extremely high. If dehydration is the cause of the elevated BUN, then the values do not tend to be as high. The BUN must be interpreted in conjunction with a urine test called specific gravity to know if the BUN is elevated due to kidney disease or dehydration. Liver disease and nutrition can also influence the level of BUN.

Creatinine

It is the most accurate way to diagnose kidney disease, and is more reliable than BUN, since factors like dehydration are not as influential on creatinine as they are on BUN. This test is also a good early indicator of kidney disease even when normal, if the trend in values is increasing. This again emphasizes the importance of yearly wellness exams as your pet ages. If the creatinine is going up, even if in the normal range, we might  start treating for a kidney problem much earlier in the course of the disease.

Phosphorous
In the more advanced stages of kidney disease the phosphorous levels elevate. This is not a good prognosis.

Amylase

This is an enzyme produced by the pancreas to aid in the digestion of carbohydrates. It is excreted by the kidneys, so an excess in the bloodstream could indicate kidney disease

SDMA

Serum symmetric dimethlyarginine is a new kidney marker that might aid in early diagnosis of this malady. Increases in this test occur prior to increases in serum creatinine if a normal creatinine is considered 2.4 or less.

CRF-SevereAzotemia

This is an actual blood panel from a typical pet with severe CRF. Click on it to see the details. It shows just how advanced this problem can become in cats before owners bring their pet in for treatment. We need to catch this problem long before it gets to be this severe and there is little we can do.

Urinalysis

This is also an important tool in the diagnosis of kidney disease and another early indicator of kidney disease along with creatine. Changes in several parameters could indicate kidney disease:

Specific Gravity (S.G.)

The ability of the kidneys to dilute and concentrate the urine is an important parameter to monitor. Water has a specific gravity of 1.000. A pet with kidney failure has a specific gravity of between 1.008-1.012. A specific gravity in this abnormal range is called isosthenuria. In cats with normal kidney function, the S.G. should be greater than 1.035, in dogs it should be greater than 1.025.

This number is interpreted in conjunction with the BUN to help determine if the elevation in BUN is due to dehydration or kidney disease. To complicate things further, dehydration and kidney disease can occur simultaneously. Also, as mentioned above, liver disease, a common problem in older pets, can also be an influence. To be accurate the specific gravity should be checked immediately after obtaining a urine sample.

Protein

Excess protein in the urine, called proteinuria, is a common finding in CRF. It can also occur in glomerulonephritis, pyelonephritis and amyloidosis. There is evidence to suggest that urine protein:creatinine ratio can be a predictor of survival time. Cats with a ration < 0.4 tend to live significantly longer than cats with a ratio > 0.4.

This cat as a high ratio, indicative of kidney disease

Cells

Specific types of cells, called casts, can also be an indication of kidney disease. We interpret the casts with the specific gravity.

This cat has a normal Specific Gravity, with no protein and no casts. This is normal, it does not have kidney disease based on this urinalysis, and what we want to see on this test in cats. 

Urine Culture and Sensitivity

If pyelonephritis is suspected, or bacteria are noted in the urinalysis,  the urine should be cultured to determine which bacteria if any is present. If a bacteria is grown out then the appropriate antibiotic should be used for 4-6 weeks.

This culture grew out a Staph organism. Many urine cultures grow out a bacteria called E. Coli, which most people have heard of. The “E” stands for Escherichia. 

If an organism is grown out, many different antibiotics are tested to see which one is most effective. The “S” in this sensitivity means that this Staph. bacteria is sensitive to that antibiotic. If the bacteria was resistant to that antibiotic, there would be an “R”.

Radiography

Radiography can be very helpful in the diagnosis of kidney disease. It allows us to visualize the kidneys, check for stones in the urinary system, look for calcification that might go along with kidney disease, and also look at other organs that commonly have a problem as pets age.

These kidneys have a normal size and shape. Use this for comparison purposes as you look at the other radiographs.

This is the radiograph of a cat with normal kidney’s that is laying on its right side. The right kidney (RK) usually lies forward in the abdomen compared to the left kidney (LK). The area of the 2 kidney’s that overlaps is more whitish in nature.

This is the radiographic of a cat with renal lymphosarcoma (malignant cancer). The diseased kidney is the large white circular area in the center of this view. It is pushing the large intestine down.

Here is different cat with renal lymphosarcoma. It is a different view from the one above. Both kidneys ( K ) are involved in this cat.

Ultrasound

A very valuable tool in the diagnosis of kidney disease is ultrasound. It allows us to look at the ureters and bladder, internal anatomy of the kidney, measure kidney size, and take a biopsy for an accurate diagnosis. In many cases the use of ultrasound precludes us from having to perform an exploratory surgery.

This is an ultrasound of the right kidney, which is being measured to determine its size

Excretory Urogram

This special test, also know as an IVP (intravenous pyelogram) gives us significant information about the renal system. It has to be used carefully if ARF or CRF is suspected because it can exacerbate the problem. A radiopaque dye is injected into the bloodstream and radiographs are taken of the dye as it passes through the kidneys, ureters, and bladder.

This picture shows how the dye outlines the center of each kidney, called the renal pelvis (remember the renal pelvis in the anatomy picture at the beginning of this page?).

Laparotomy

Exploratory surgery (laparotomy) is frequently used as an aid in the diagnosis and treatment of renal disease, especially cancer. We use this option when we feel that ultrasound will not be advantageous.

The arrow points to a lump on the surface of a kidney. It was caused by cancer that spread from the stomach.

A section of the lump was biopsied during surgery to determine the cause. The tremendous blood supply to the capsule that surrounds kidneys can easily be visualized. Even though this capsular blood supply is extensive, it pales in comparison to the amount of blood that flows into and out of the kidneys through the renal artery and veins.

Three sutures were placed in the kidney capsule to control the bleeding that occurred at the biopsy site

A biopsy of a lymph node (called cranial mesenteric) located in the center of the abdomen was also obtained. This helps us determine if the cancer has spread.

cancerouskidney

This is what cancer looks like inside a kidney that has been cut open. The the left side of this open kidney the cancer goes from the 7 PM to 1 AM mark.

Treatment

Acute Renal Failure

This form of renal disease needs immediate and aggressive treatment to prevent death. In some instances we will send you to a referral center that has dialysis equipment to filter the blood of waste products while your pet’s kidneys recupterate.

Cats that have a urinary obstruction need to be unblocked immediately. If not, excess potassium in the bloodstream (hyperkalemia) can cause death to to its affects on the heart.

Any drug suspected of causing the problem is stopped immediately, and underlying problems are addressed. Fluid therapy is critical, and consists of saline and dextrose solutions initially. Fluid therapy corrects fluid and electrolyte imbalances, increases the blood flow to the kidneys, and starts the process of diuresis.

Cats need to maintain their caloric input in order to minimize the metabolism of protein for their caloric needs. Metabolizing excess of amounts of protein will increase uremia, causing a further deterioration in condition.

Pets that are still not urinating after this initial fluid therapy are given Lasix or mannitol. Excess potassium (hyperkalemia) is a common finding in ARF. If mild, fluid therapy alone should correct the problem. If severe, regular insulin and sodium bicarbonate are used. Pets with ARF are sensitive to ulcers and infections, so treatment for these problems is sometimes initiated.Ethylene glycol (antifreeze) poisoning is an example of ARF.

Pets that have heart disease are sensitive to IV fluids because excess amounts can cause an overload to the lungs called pulmonary edema. These pets pose a dilemma. If we do not give them enough fluids the kidney problem will worsen. If we give enough fluids to help flush the waste products out of the bloodstream, these same fluids might cause pulmonary edema.

This radiograph is of the chest of a normal dog. The heart (H), windpipe (W), and lungs (L) are labeled. The lungs are black because they are filled with air. This is how normal lungs look on a radiograph.

This dog has pulmonary edema. The air filled lungs are no longer black, they are white from the fluid that has built up. This is a very serious condition.

Chronic Renal Failure

This is the version of kidney disease we encounter most often. The prognosis is guarded, and depends significantly on how long the disease process has been present along with your pet’s age. Pets (usually geriatric) that have other diseases  that are common at this age can make this difficult to treat if not caught early enough.

Many pets (especially cats) that are brought to our hospital have CRF that has progressed to the point where the problem has become similar to ARF. These pets need to be hospitalized and put on intravenous fluids almost continuously to get them over this acute phase. We will closely monitor their BUN and creatinine before therapy is instituted and during hospitalization, to ascertain if their kidneys are responding to fluid therapy. If the BUN and creatinine do not drop significantly after 24-48 hours of intravenous fluids then the prognosis for recovery is poor.

Many treatments have been advocated to help minimize the symptoms of CRF (also called the uremic syndrome). None of them can cure the problem, and not all of them have proven to work, so it is important that we tailor make each pet’s therapy to its individual needs. In addition, indiscriminate use of medication to treat a perceived problem can make the kidney disease worse. This applies to almost every drug, since the kidneys are so intimatley invovled in the metabolism of drugs. The medical axiom of “first do no harm” applies directy to kidney disease.

Medical management of CRF needs to address the following:

Protein and phosphorous regulation

XS protein in the urine

High blood pressure

Anemia

Dehydration and electrolyte imbalance

Low pH in the bloodstream

Stomach and intestinal ulcers

It is sometimes easy to forget some of the more common sense remedies that are available to treat diseases, especially true in kidney disease with all the web sites and advice from people who have encountered this common problem. Fresh water should be available at all times for your cat. You should fill the water bowl at least 3 times per day to help stimulate drinking. Undue stress should also be minimized at all times also.

Diet

Pets with CRF need to be fed a diet that has limited amount of high quality protein. Less protein in the diet leads to less work the kidneys have to perform by removing the nitrogenous waste products that are the end result of protein metabolism. Protein is vital to all bodily functions and can not be indiscriminately limited. As a matter of fact, if protein restriction is not implemented carefully it can make the uremic syndrome worse.

High quality protein means that it contains more essential amino acids, which are those the body cannot produce and must be obtained in the diet. The commercial food that we recommend for kidney disease is called K/D©. It is made by Hills© and is available only from a veterinarian because it is used to treat a specific disease. In addition to high quality protein it also has less phosphorous and sodium.

This food is the gold standard for CRF, and has been used successfully for decades to slow down the progression of CRF and give your pet a very good quality of life. If your older cat has arthritis, which is not uncommon, using the K/D with mobility will help for both problems.

Most cats take readily to K/D, although it can sometimes be difficult to change the diet on an older cat. Many of the cats are eating poorly and have already lost weight due to the kidney disease, so we don’t want to add to their problem by feeding a diet they won’t eat. Mixing this new food in partially with the regular diet and heating it up a little (for the canned food) in the microwave helps. adding a small amount of a tasty fluid like clam juice can make it taste better.

The use of appetite stimulants, which you will learn about below, are benificial here. It is important to keep your cat eating so that it does not lose muscle mass.

Water soluble vitamins (ex.- B-complex vitamins) are easily depleted in a pet that has PU/PD. Supplementation can be helpful.

Do not use foods that are lableled “for urinary health”. They are treating a different problem called FLUTD. These foods change the pH of the bloodstream in a way that is detrimental to the kidneys.

Phosphorous lowering medication

Pets with CRF might have an increase in their phosphorous levels as the disease progresses. This excess phosphorous can add to the anemia that is common with CRF. It will also dramatically influence calcium metabolism in the body through a hormone called parathyroid hormone. The end result will be painful calcium deposits in the bones and internal organs, including the kidneys. This will also add to the scarring and add to the progression of CKD.

As already mentioned, K/D©is restricted in phosphorous, and should be used in combination with phosphorous binding medication. The phosphorus binding medication we use, which always needs to be given with food, is called Epakatin by Vetoquinol©.

Potassium increasing medication

Pets with CRF will have a decrease in their potassium levels as the disease progresses. This does not always show up on a blood panel. Using oral supplements and adding additional potassium to fluids helps counteract this problem. Oral potassium is called Renal K+©, and it comes in a paste for easier administration.

Urine protein reducing medication

Reducing protein in the urine is believed to help slow down the progression of the disease. ACE (Angiotensin Converting Enzyme) inhibitors (ex- Enalapril) or ARB’s (Angiotensin Receptor Blockers) are used when the urine protein:creatine ratio is greater than 0.5 in the dog and greater than 0.4 in the cat. These drugs are given for 30 days and then the urine is checked to see if there is either a 50% reduction from the original test, or if the ratio is below 0.5 in the dog and 0.4 in the cat.

Anemia fighting medication- Darbopentin

One of the long term affects of CRF is anemia due to a lack of erythropoietin secretion from the kidneys. This hormone can be supplemented to help minimize anemia.

Fluids

One of the most important treatments for CRF is the administration of supplemental fluids. Whenever we tell people their pet with kidney disease needs fluids they commonly respond “its OK, he/she already drinks a lot of water”. Unfortunately, this excess drinking of water is a result of kidney disease, and not a sign that the pet is drinking adequate amounts of water. Cats in particular are not good drinkers, and need additional water to what they are already drinking.

If your pet is hospitalized we will give them intravenously (IV) because of greater effectiveness and accuracy. If your pet responds to IV fluids during its hospitalization we will initiate the use of subcutaneous (SQ.) fluids at home on a daily basis.

This area of home treatment is so important that we have devoted a complete page to its use. Please click here to learn about the proper technique, then return to this section for more treatment options.

Most cats with CRF should receive between 50 ml and 100 ml of SQ fluids at least several times per week. As the problem progresses it will become necessary to give this fluid on a daily basis. We commonly add B-complex vitamins to the fluid bag since these water soluble vitamins are excreted the more we give supplemental fluids. Feeding a food designed for kidney disease like K/D will also help minimize the depletion of water soluble vitamins.

Blood pressure medications

Hypertension is a common occurrence as the disease progresses. Any systemic blood pressure of 160 mm or more should be treated. Blood pressure lowering medications like Norvasc (calcium channel blocker) and Enalapril (ACE ihnibitor) will help counteract this problem. All cats initially diagnosed with CRF should have a blood pressure taken. It should be rechecked at least every 6 months.

Some cats might respond to ACE inhibitors to decrease the protein in their urine. Further studies are needed in this area to determine efficacy.

Anti-ulcer medication

Some cats with CRF don’t eat well because of nausea due to excess hormone secretion in the stomach. Tagamet or famotidine is used to counteract this problem. If we suspect an ulcer in the stomach due to the toxins that have built up we will use Tagamet also.

Anti-vomiting medication

Vomiting is a common problem in pets with CRF. It occurs as a result of uremic toxin buildup in the bloodstream and alterations in hormones that regulate gastric secretions. Vomiting will cause dehydration, leading to a decreased flow of blood to the kidneys (decreased GFR) and an increase in azotemia. We use a drug called Reglan  or Cerenia to alleviate vomiting symptoms.

Antibiotics

Animals weakend by kidney disease are more susceptible to infection. These pets are commonly older and have significant dental disease. Antibiotics help them fight off infections. The antibiotic dose might have to be adjusted since many of them are removed from the body by the kidneys. Pets with CKD commonly have urinary tract infections due to bacteria, so a urine culture and sensitivity is needed in these pets to see if this problem is present.

Anti vomiting medication

Pets with CKD are commonly vomiting. This is a sign of how sick they are, and it also precludes them from getting proper nutrition, which is crucial in the treatment. Putting these pets on Cerenia, a very effective anti-vomiting medication, is necessary if your pet is vomiting. There is an injectible form of this drug used in an acute case, and an oral version for long term use.

Appetite stimulant medication

Pets with CKD do not eat well for many reasons. Getting them to eat is crucial, and some of them need appetite stimulants. The most effect ones we have found are Periactin and Mirtazapine. Mirtazapine comes in a topical version if you cat is not eating well.

Probiotics

 This supplement digests non-protein nitrogen in the intestines, mininizes BUN and creatinine levels, so there is less work for a diseased kidney.

Feeding Tubes

This overlooked and effective treatment helps dramatically for cats with CKD that are not eating well, are vomiting, and are difficult to medicate orally and with SQ fluids. We have a detailed page on feeding tubes.

Miscellaneous treatments

There are other supplements and medications used in CRF that might be of some benefit, although this is unproven. As long as they do not cause the problem to worsen they might be worth trying. Anabolic steroids– They are also used in older pets for arthritis and appetite stimulation with good success. They might help counteract the affects of anemia, although this can not be relied upon. DecaDurabolin  is the one we used most frequently. Drugs like this are no longer readily available. Calcitriol– It is postulated (there is no proof) that some of the symptoms of CRF are the result of elevated levels of parathyroid hormone. This hormone helps in the regulation of calcium levels in the bloodstream. By adding low doses of the hormone calcitrol the parathyroid hormone will be suppressed, and your pet might feel better. The phosphorous level must be controlled, and the calcium level monitored closely, if one of our doctors decides to use this modality.

Kidney Transplantation

At some select veterinary universities (University of Georgia) a new kidney can be transplanted into a cat. This does not cure the problem, it is a help in controlling the problem in cats that are losing weight and are anemic in spite of medical therapy. This specialized surgery can cost upwards of $10,000. Your cat has to be kept on immunosuppressive therapy (cyclosporine and prednisone) the rest of its life, and the donor cat has to be adopted. Complications can occur, especially rejection of the new kidney.

This is Skipper with his wonderful mom in for special testing before he goes to Georgia for his kidney transplant

Skipper2

This is a picture of him during the surgery. The organs are labeled below for your understanding. 

The old, swollen, and diseased kidneys are labeled. The new kidney is circled

Skipper1

Skipper returned several months later feeling much better, and with his new brother!

Prognosis

Pets presented with renal disease, whether ARF or CRF, carry a guarded prognosis. It can be successfully controlled in most circumstances, especially if the diagnosis is made early enough. We talked about this at the beginning of this page by recommending that all cats at 8 years of age be fed Hill’s K/D Early Support.

If your pet is hospitalized with CRF we will closely monitor its blood panel, paying special attention to BUN, creatinine, and phosphorous. If the excess levels of these tests decrease dramatically during hospitalization, and your pet improves clinically, then the use of K/D food, medications and SQ fluids at home are usually advantageous.

All pets that have been diagnosed with CRF should have a blood panel, a urinalysis, blood pressure check, and physical exam performed every 3-6 months. This disease will progress, and other diseases might present themselves, so this type of monitoring is crucial for a good quality of life.

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Diabetes Mellitus (Sugar Diabetes)

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This page describing diabetes mellitus (DM) is very thorough and will require some study if you want to understand it fully. There is a different kind of diabetes, called diabetes insipidus, which is not the same disease. In general, when most people say a pet or a person has diabetes, or  if they also say sugar diabetes, they are refurring to diabetes mellitus.

Sugar diabetes, more correctly know as diabetes mellitus (DM), is a complex disease that is difficult to control, particularly in cats. Proper treatment requires a commitment on your part, usually for the life of your pet. It is well worth the effot in most cases because response to treatment is usually quite rewarding.

By definition, DM is a persistent hyperglycemia and glycosuria due to an absolute or relative insulin deficiency. By the time you are done with this page you will understand what all of this means.

You will also learn that some of the parameters of DM in animals are similar to humans, and many parameters are not, so be careful of extrapolating any experience you have between the two. DM can occur in many different species like birds and Guinea Pigs, although it is most commonly diagnosed in dogs, and especially cats.

Obesity is a big reason pets get DM. Fat is not just fat, it causes inflammation, leads to the rise of insulin resistance, which means your pet gets DM and does not respond well to insulin treatment. Most obese cats are prone to be what is called prediabetic. It all has to due with a hormone called amylin elevated in the bloodstream of overweight cats.

Other facts influence diabetes mellitus. An important one is dental disease. The infection in the mouth can make it difficult to regulate a diabetic cat. We have a detailed page on dental disease to learn more about this.

Chronic pancreatitis can also predispose your cat to getting diabetes mellitus. We have a page on this (which includes inflammatory bowel disease) to learn more about pancreatitis.

You can go far in preventing DM by keeping your pet at a normal weight, and feeding your cat a food that is higher in protein and lower in carbohydrates. Routine exams, that include blood panels and urinalyses that both monitor glucose, are important as your pet ages.

We have a summary page on DM if this page has too much information for you.

It will help if you learn these medical words because they will be used on this page:


Normal Physiology

The ability to use a food source for energy is critical to the success of any species, therefore nature has very sophisticated mechanisms to regulate this process. These mechanisms are extremely complex, and only those mechanisms that relate to diabetes mellitus will be summarized for the sake of simplicity.

In response to a decreasing blood glucose level the appetite center in the brain is stimulated and hunger ensues. A meal is then eaten, which consists of fats, carbohydrates, and proteins, in different percentages. When these fats, carbohydrates, and proteins are broken down by the digestive system and absorbed into the bloodstream, they are used by the body for various functions. The main function of the carbohydrates is eventual conversion to an energy source in the form of glucose, the primary energy source for all cells in the body. Some of this glucose is stored in the liver in the form of glycogen, which is released and converted back to glucose when cells need energy in-between meals.

Carbohydrates can be complex or simple. Complex ones are bread and pasta, simple ones are lactose (the carbohydrate in milk). When these carbohydrates are absorbed in the bloodstream through the intestines they are converted to glucose by the liver. The simple ones, like lactose, are rapidly converted and will immediately raise the blood glucose level. The more complex carbohydrates take longer to be metabolized to glucose by the liver, as a result they raise the blood glucose level more slowly. This point becomes important when treating both hyperglycemia and hypoglycemia.

Once in the bloodstream the glucose that circulates throughout the body is available for use by all cells as their primary energy source. These individual cells cannot absorb this glucose that passes by in the bloodstream unless the hormone insulin is circulating in the bloodstream at the same time. Insulin causes a chemical reaction in the cell wall that allows the glucose to enter the cell. The only cells in the body that do not need insulin to absorb glucose are specific brain cells.

Insulin originates in a group of cells called the islets of langerhams that are located in the pancreas. Insulin comes from the beta cells in the islets. It is secreted into the bloodstream in response to an increase in glucose in the bloodstream, a normal occurrence after a meal is eaten. The higher the glucose level the greater the amount of insulin secreted. Since the absorption of simple carbohydrates will cause a more rapid increase in blood glucose there will be a more rapid increase in insulin secreted. The complex carbohydrates will cause a more gradual rise in the insulin level.  This fact becomes important in feeding a diabetic patient.

The normal physiology is even more complex. Insulin also has a large effect on fat and protein metabolism. In addition, the pancreas also secretes a hormone called glucagon in response to a decreasing blood glucose level. Glucagon originates from the alpha cells in the islets, and its role is to help the liver convert glycogen back to glucose. As can be expected, glucagon will increase the blood glucose level, and counteracts the blood glucose lowering effects of insulin. Insulin and glucagon work in a negative feedback loop that allows for a very refined system to keep the blood glucose level at an optimal level for the energy requirements of each individual cell. The liver is a major part of this loop, acting as a blood glucose buffer to keep the blood glucose at optimum levels. This is a highly refined process that is fine tuned over thousands of years and works extremely well.

In general, brain cells do not need insulin to utilize glucose. A specific area of the brain, called the appetite center (in the hypothalamus), monitors the amount of glucose that circulates in the bloodstream. The lower the blood glucose level in the cells in the appetite center the greater the appetite. Unlike most of the brain cells, the ability of glucose to enter the cells of the appetite center is dependent upon insulin. In diabetes mellitus, with its lack of adequate insulin in the bloodstream, these appetite center cells don’t monitor glucose levels properly, thinking the blood glucose is low. As a result, the pet develops polyphagia to correct for this perceived problem. The additional food that is then eaten further increases the blood glucose level.

The pancreas does more than secrete insulin and glucagon into the bloodstream. It is the primary source of enzymes that are secreted into the small intestines (not bloodstream this time). These enzymes are secreted in response to the presence of food in the digestive tract, and are the primary way that many nutrients are broken down and absorbed by the intestines into the bloodstream. The way these energy sources are acted upon by the enzymes, and how they are eventually utilized by the liver, are also factors that effect the blood glucose level.

To further complicate the picture, epinephrine (adrenaline), cortisol (cortisone) and growth hormone also influence the blood glucose level.

This is a picture of the pancreas of a cat. It is adjacent to the beginning of the small intestine called the duodenum. The pancreas is the pinkish tissue directly under the cylindrical duodenum. For such a small organ it has an important job.

Now that you are an expert at normal physiology, lets learn what happens when the normal mechanisms described above go wrong. This is called pathophysiology. What causes this pathophysiology, leading to a lack of insulin production by the pancreas? It is multi-factorial, and includes:

  • Genetic predisposition
  • Infection
  • Toxins
  • Inflammation

Obesity and a lack of physical activity are predisposing factors, especially in cats.

Pathophysiology

The relative lack of insulin causes the blood glucose to go abnormally high. Normal blood glucose in a dog or cat varies from 80 to 150, but can temporarily go much higher (300-500 or more) in stressful situations. When the blood glucose is consistently high, as seen in diabetes mellitus, several negative effects occur.

Many diabetic cats will start having a rise in their blood glucose levels before the onset of symptoms, and before the beta cells in the pancreas lose their abilitly to secrete insulin. If we can catch this early, insulin secretion might possibly be restored. This emphasizes the importance of yearly exams with a blood panel and urinalysis to screen for this.

Inadequate insulin levels force the cell to perform its functions with alternative sources of energy besides glucose. This causes problems for the organ that is made up of these cells, and eventually will lead to significant disease and the complications that occur in untreated diabetes mellitus.

The cells of the body (except most brain cells) are deprived of their primary source of energy. This means they do not function at optimum efficiency. Since they are starved of glucose they need to rely on other sources of energy, namely fat and amino acids. These are not as good an energy source as glucose in the long run.

To utilize amino acids as an energy source the body needs to break down protein. A large part of this conversion occurs in the protein in muscles cells. As this conversion from protein to amino acids progresses the body loses its muscle mass and weight loss occurs.

Metabolism of fat as an energy source is a normal response when cells do not receive adequate glucose for their energy. In the short term this process is highly advantageous. Fat has twice as much calories as proteins and carbohydrates, so it is a concentrated source of energy in the short run. If the fat metabolism process goes on for a prolonged period of time it becomes detrimental, and leads to the buildup of byproducts from fat metabolism. The main byproduct is a compound called ketones.

The ketones that build up in this process change the pH of the blood, further dehydrate a pet, interfere with other metabolic processes, and cause fatty infiltration of the liver. Ketones also cause vomiting, which leads to further inappetance and additional dehydration and electrolyte imbalance. Further inappetance causes the cells to use even more fat as an energy source, causing an uncontrollable spiral, and sometimes even death. Any diabetic pet presented with ketones in its urine is a medical emergency. These pets have what are termed diabetic ketoacidosis, abbreviated as DKA.

In addition to the liver, the kidneys are another important organ in this disease. The primary role of the kidneys is to filter the blood. As the blood passes through the kidney filters essential nutrients are returned to the bloodstream and waste products are excreted through the urinary system. Glucose is one of the many molecules that is returned to the bloodstream after it has passed through the kidney filters. Once the glucose exceeds 200 mg per deciliter (this varies by species, cats tend to be higher) in the bloodstream though, the kidneys can no longer selectively return all of this glucose back into the bloodstream. This is called “exceeding the renal threshold”, and is a very important part of diabetes mellitus.

As a result, glucose spills into the urinary tract and bladder in excessive quantities. Since glucose attracts water (called the osmotic effect) it pulls fluid out of the pet and causes polyuria. To compensate for this excess urination the pet drinks more water, and now has polydypsia. It now has the symptoms we abbreviate as PU/PD. Eventually it causes dehydration when the pet can’t drink enough water to keep up with the increased urination. In addition, the excess urination pulls important electrolytes out of the bloodstream like sodium and potassium, which leads to lethargy and weakness. The loss of glucose also depletes the body of its primary energy source, so additional weight loss occurs. To further add to a diabetic pet’s woes, the excess glucose that builds up in the bladder feeds bacteria that can cause a urinary tract infection.

Why the pancreas stops secreting adequate levels of insulin is a mystery. There is a strong correlation for diabetes mellitus to occur in cats that previously had an episode of pancreatitis. This makes sense because the pancreas is the source of insulin. Yet, many cats that have diabetes mellitus had no apparent pancreatitis in the past. In some pets the immune system attacks the beta cells in the islets and deposits a compound called amyloid which, makes the beta cells unable to secrete insulin. This amyloid, which contains a protein called amylin, is thought to play a significant role in non-insulin dependent diabetes (your will learn about this soon) because amylin is toxic to the cells in the islets of langerhams.

Another factor involved in non-insulin dependent diabetes is peripheral insulin resistance. This resistance plays a significant role in obese pets, which is a major predisposing role in the development of insulin. Genetics is also involved-genetics cannot be controlled, but obesity can.

Elevated levels of thyroxine, which occurs in feline hyperthyroidism, can also be a factor in insulin resistance.

So what does all of this mean? To summarize all of this pathophysiology:

    • Peripheral insulin resistance, due to obesity and/or the protein amylin found in amyloid, causes chronic stimulation of insulin production in the pancreatic beta cells.
    • Impaired insulin secretion causes insulin and amylin to accumulate in beta cells in the pancreas.
    • The high levels of amylin in the beta cells allows amyloid to deposit, further disrupting the ability of these cells to produce and regulate insulin. As the problem progresses non-insulin dependent diabetes eventually progresses, and at some point in time, the symptoms of diabetes mellitus appear.
      The pancreas can get a tumor called an insulinoma. In this case the pancreas secretes too much insulin and the blood glucose hovers at dangerously low levels. This problem is rare in most animals except for the ferret

Classification

Most people are familiar with the classification scheme used in human medicine. Even though the disease is similar in people and pets, the human classification scheme does not always correlate with diabetes mellitus in cats. Differentiating between Type I and Type II in cats can be difficult.

  • Type I

    Has similarities to insulin dependent or juvenile onset diabetes mellitus. Most commonly occurs in middle aged cats. Insulin is needed to treat the problem. This is also known as insulin dependent diabetes mellitus (IDDM).

  • Type II

    Similar to adult onset or non-insulin dependent in humans. Obesity is a significant risk factor. Insulin is not needed in all cases. Type II cats can become Type I cats when exposed to significant stress. Fortunately, when the stress is resolved they can revert back to Type II. This is also known as non-insulin dependent diabetes mellitus (NIDDM).

    Diabetes can occur secondary to other problems. Some of these problems include hormone imbalances and reactions to medications. A medication called Ovaban, a hormone used to treat numerous cat ailments, can cause diabetes if used excessively.

Symptoms

The classic signs of a cat or dog with diabetes mellitus are PU/PD. These signs of excess drinking and urinating are subtle at the beginning stages of the disease and are easily missed. This is especially true in outdoor cats who do most of their urinating outside, and dogs that urinate outside also.

Other symptoms include weakness, an increase in appetite, occasionally a decrease in appetite, weight loss, lethargy, and rarely, vision problems due to cataracts (this problem is more common in dogs). Cats with a severe liver problem associated with this disease might have icterus (jaundice).

An affected cat might even walk abnormally on the rear legs (called plantigrade posture) due to nerve problems as a consequence of the elevated blood glucose level. It is also known as diabetic neuropathy, and tends to occur as the disease progresses. The best way to prevent it is to keep the blood glucose level as close to normal as possible.

This is what the abnormal (plantigrade) posture looks like

These are also the symptoms of other diseases commonly seen in dogs and cats, and can only be differentiated by diagnostic tests. These other diseases include, but are not limited to, hyperthyroidismkidney diseasecancerliver diseaseCushing’s disease and adverse reaction to medications.

The yellow discoloration to these gums is icterus (jaundice). It is commonly, but not always, caused by liver disease.

Symptoms in dogs typically include:

  • PU/PD
  • lethargy
  • poor appetite
  • vomiting
  • weight loss
  • diarrhea
  • cataract formation

Just like in cats, many dogs with diabetes mellitus were overweight at some time in the recent past.

Dogs with diabetes commonly have other diseases concurrently. They include:

Diagnosis

By the time a diagnosis of diabetes mellitus is made the disease process has usually been present for a significant period of time. When the disease process first started there were no obvious symptoms because of compensatory mechanisms in the body. As diabetes progresses these compensatory mechanisms lose their ability to maintain euglycemia. Eventually, symptoms of PU/PD and weight loss occur and your pet is brought in to be examined. This emphasizes the point that middle aged and older pets should have a routine blood panel and urinalysis every year once they reach 8.

This is a complex disease, and no specific set of symptoms tells us your pet has diabetes mellitus. It is important to follow the tenets of the diagnostic process closely when making a diagnosis of diabetes mellitus, especially since kidney disease and hyperthyroidism have similar symptoms. We will use the diagnostic process as an example of how we make this diagnosis:

Signalment

Typically this disease is seen in obese cats that are middle aged or older, and more commonly in males (the opposite of dogs). Orange cats seem to get DM more often than other colors, but that could be because more of them are male. There is no specific breed predilection in cats.

Dogs are typically middle aged and older, with purebred dogs showing a higher incidence. Common breeds are:

History

The classic signs of PU/PD, polyphagia, and weight loss occur in many cases, but not all. These signs depend on how well entrenched the disease process is before your pet is brought in for an examination. Sometimes the only thing an owner notices are accidents around the house in a previously housebroken cat.

A consistent finding is obesity in the recent past. This predisposes them to DM, and we sometimes call them pre-diabetic if obese enough. These obese cats need to be closely monitored for DM with fasting blood glucose tests, urinalysis, and fructosamine tests. You will learn about these tests in or diagnosis section.

Since this disease occurs in middle aged and older pets there can be other diseases occurring simultaneously. Some cats have a history of vomiting in the recent past, an indication that they might have had an episode of IBD (Inflammatory Bowel Disease) or pancreatitis. Some cats are borderline diabetics that have had a recent illness, stress, or adverse reaction to medication. There might also be blood in the urine or straining to urinate, an indication of a urinary tract infection.

Cats presented in DKA might have a history of abdominal pain and distention, vomiting, inappetance, and lethargy.

Physical Examination

The findings of the physical exam depend on how severe the diabetes is, how long it has been present, what caused it, and if there are any other disease processes occurring simultaneously.

Many cats will have lost weight, yet they still could be obese. There might be dehydration, weakness, lethargy, an enlarged liver on abdominal palpation, and an acetone (juicy fruit) smell to the breath. Hypothermia and shock could be present in advanced cases and those with DKA.

Diagnostic Tests

The primary method of diagnosis is with a fasting blood panel and a urinalysis. The blood panel will reveal hyperglycemia (at least > 200 mg/dl) while the urine sample will reveal glycosuria. Not every case of hyperglycemia means a cat has diabetes mellitus. Cats that recently ate, or those that eat canned foods that are rich in sugar, might have blood glucose levels higher than the normal range. Cats that are stressed from a car ride, on cortisone, are in heat, on phenobarbital medication or hormone medications, might also have hyperglycemia.

Cats are unique in that their stress response can cause a tremendous rise (up to 4x normal) in the blood glucose. This is a common occurrence when we take a blood sample in a cat, and needs to be taken into consideration when we analyze a blood report. This stress induced response is a normal reaction to the release of epinephrine (adrenaline). It is a transitory response and will not persist like the hyperglycemia of diabetes mellitus. These cats sometimes need to adjust to a hospital environment before we are able to determine their true blood glucose level. It is always advised to check the blood sugar in dogs and cats after an 8-12 hour fast to give an accurate representation of the blood glucose level.

Here is a blood glucose report from our lab for a cat that does not have diabetes mellitus. The blood glucose is 317.

This cat has diabetes mellitus, its blood glucose is 390

How do we differentiate them when both are well above the normal range?

Diabetes mellitus is diagnosed when there is a persistent fasting hyperglycemia along with glycosuria, that is consistent with a history of PU/PD and polyphagia.

Other blood tests are sometimes used in this disease. The two more common ones are serum fructosamine and glycosylated hemoglobin. They are used to to distinguish stress induced hyperglycemia from diabetes mellitus, and to also monitor insulin therapy. They give us an indication of what the blood glucose level has been for the preceding weeks.

Fructosamine is formed when glucose reacts with amino acids that make up serum proteins like albumin, which is made by the liver. When the blood glucose is high, fructosamine also increases. Increased levels of fructosamine help confirm a diagnosis of diabetes mellitus, give us an idea of the presence of a persistent hyperglycemia, and help us monitor response to treatment.

Glycated hemoglobin (HbA1c), a tool to diagnose, monitor, and treat diabetes mellitus in people, is just start to get clinical application to dogs and cats with DM. This hemoglobin A1c test gives us a greater timespan to monitor glucose levels, up to 70 days in cats and 110 days in dogs, as opposed to fructosamine which monitors glucose levels for several weeks.  The A1c test is is not affected by daily blood glucose fluctuations, exercise, diet, or the amount of insulin in the bloodstream. As this test is tested for consistency and become standardized and cost effective we will implement its use as another aid to monitor and treat or diabetic patients.

In addition to glucose in the urine and ketones, the urinalysis might indicate that a urinary tract infection is present. This is detected by a change in the pH of the urine, excess white or red blood cells, and bacteria. Even if these are not present a urinary tract infection can still be present. This is why we recommend a urine culture and sensitivity looking for bacteria.

This is a urinalysis from a cat that has diabetes mellitus. Its glucose is 4+. Fortunately, it is negative for ketones, there are no white or red blood cells present, and there are no bacteria visible either.

This cat does not have ketonuria or an infection.

Treatment

The goal of treatment is to resolve the symptoms of poor appetite, lethargy, and PU/PD without inducing hypoglycemia. Dogs tend to be easier to regulate than cats, although preventing cataracts from forming is difficult in the dog.

Some cases of diabetes mellitus in cats are not straightforward. An obese cat can have NIDDM in its normal, unstressed home environment. These cats are secreting insulin but in low levels. As long as they are in a stress-free environment they are able to maintain euglycemia. If they encounter a stressful situation, get sick, or are put on certain medications, their blood glucose will increase. If it goes beyond the renal threshold for glucose, PU/PD will ensue.

These cats are then brought to a veterinarian because of the PU/PD and diagnosed as having diabetes mellitus. They are put on insulin therapy and the problem improves. The problem occurs when these cats are returned to their normal environment and the problem that started the increased blood glucose in the first place (stress, illness, drugs) is now gone. In some of these cases these cats will now become hypoglycemic because they are being given insulin injections when they do not need them. Identifying these cats that have converted from insulin-requiring to non-insuin requiring NIDDM is difficult. This is one of the numerous reasons why diabetic cats should be brought to our hospital every 1- 3 months for a urinalysis and blood glucose curve.

If we start a cat on insulin injections, it’s weight is or becomes normal, and it responds well to insulin injections (especially glargine), we might have a cat in remission, which is our ultimate goal.  In these cases we start lowering the insulin dose slowly, over several weeks to see if it still maintains a normal blood glucose.

Hypoglycemia, blood sugar that is too low, is your primary emergency problem. Symptoms to watch for include:

  • Walking abnormally, like your pet is drunk
  • Running into walls or circling
  • Staring into space
  • Shaking

All diabetic animals, especially cats, need to be closely monitored because urine and blood glucose levels are in a constant state of flux. Because of this you need to be in touch with your pet’s habits and observant of any changes. You also need to have Karo syrup available at all times for dogs and cats in case their blood sugar becomes low and they have problems. If you have no Karo syrup make up some sugar water and rub it on the gums.

Diet

Recent evidence suggests that feeding a high protein diet will help cats with diabetes mellitus.  This higher protein diet mimics what a cat’s physiology has been used to for millenniums. It leads to less release of hormones that affect blood glucose levels. Some cats on high protein diets will need little if any insulin injections. Some cats that are on insulin injections to control their diabetes can actually go off insulin when put on a higher protein diet. The food we recommend is Hill’s M/D.

Dietary therapy might be all that is needed for the obese cat with NIDDM. A cat that is underweight from diabetes mellitus should not be put on a high fiber diet. Since this disease is prevalent in older cats this change in diet might be met with resistance. In these cases mix the higher fiber food with its regular diet to get some advantage of the higher diet. Do not feed foods that contain excess sugar like semi-moist canned foods.

Dogs tend to do well with Hills W/D. The most important thing to remember is consistency. Your dog and cat should be fed the food they like to eat, in the same amount, at the same time every day.

Oral Hypoglycemics

The goal of oral hypoglycemic medication is to minimize glucose absorption by the intestines and to also minimize the conversion of glycogen to glucose by the liver. They also help increase insulin secretion from the pancreas. Oral hypoglycemics need to be used early in the disease before the beta cells are exhausted. Since so many pets are brought to us well past that stage, they do not work as well as in humans.

They are used in cats that are not underweight, have negligible ketones in the urine, no indication of pancreatitis or no history of being on medication that could cause hyperglycemia. In conjunction with diet, oral hypoglycemics can sometimes help us differentiate NIDDM form IDDM. Cats with NIDDM will have significantly lower blood glucose levels when checked several days after initiating this protocol.

Some cats will vomit and might even develop hepatitis from oral hypoglycemics. Giving the medication with food helps minimize vomiting.

The main one used is Glipizide. Due to variable response and potential side effects it is not used often.

Insulin

The thought of giving injections to your pet, especially a cat, can cause panic in some people. Keep in mind it is easier to give insulin injections with the tiny needle that is used, than it is to give a cat a pill. Once we show you how easy it is you will become an expert in no time. If you make it a positive endeavor, feeding around the same time, then a small treat, or a brushing or petting session just after the injection, it will be a positive experience for both of you.

There are many types  of insulin that have been traditionally used to treat IDDM in our hospital over the decades. Unfortunately, the manufacture, Eli Lilly, has discontinued the production of many of its insulin products.


Regular

FastActing- Peaks in 2-4 hours Lasts 5-8 hours


NPH

IntermediateActing- Peaks in 8-12 hours Lasts 18-26 hours


Ultralente

ProlongedActing- Peaks in 16-24 hours Lasts 24-36 hours


This chart gives you a relative idea of their peaks and duration of action. It is important to remember that every dog and cat will react differently and will not necessarily have this same graph.

Regular insulin is used initially to treat a cat or dog if it has DKA. Once the ketoacidotic state has been reduced we use the intermediate or prolonged lasting insulin. Your veterinarian will let you know which one might be most appropriate in your situation. Sometimes we need to try more than one type of insulin. What is just as important as the type of insulin used is the familiarity a doctor has with a specific protocol.

Most pets will need insulin given every 12 hours. This should coincide with a meal. You should decide ahead of time what insulin and feeding schedule works for you and your lifestyle because consistency is of utmost importance. The same thing goes for exercise since this affects insulin. Take your dog for the same type of walk at around the same time every day when possible to increase your chance of a good response to insulin injections.

For many years the insulin used to treat cats was derived from a beef-pork combination (90% beef and 10% pork) that was used in human diabetes mellitus. The pharmaceutical companies are now relying more on human recombinant (genetically engineered) insulin.

The goal of insulin therapy is to mimic naturally secreted insulin from the pancreas as closely as possible. This can be quite difficult in any species, let alone the cat. The dose of insulin and the type of insulin that is effective will vary from cat to cat and dog to dog. Once a proper dose is initially determined at some point in time in the future this dose will probably change.

Initially, insulin is dosed conservatively in order to see an individual dog and cat’s response and to minimize any chance of hypoglycemia. After your pet has been on this initial low dose we like to do a blood glucose curve to assess where we are, then make adjustments in dose accordingly.

An ideal blood glucose level for a diabetic cat is 65-220 mg/dl. Every cat is different, and we have diabetic cats with numbers lower than this, and numbers higher than this, that are doing fine. Your feedback on how your cat is doing and eating, and also how much it is drinking and urinating, is very important.

There are many different types of insulin used. We will go over the ones most commonly used:

  • Glargine and Detemir- Ultra long acting

    Glargine, a human insulin has been successfully used in many cats. If used early in the course of the disease it is even possible to get a remission of the disease.  Those cats that do go into remission need to be monitored and kept at an ideal body weight or they might have a recurrence of diabetes mellitus.

    Glargine is more expensive than the other insulin’s used. This added expense might be worth it if your cats diabetes problem is actually cured of the problem. One of our doctors will discuss this with you and see if it is appropriate in your situation.

    Glargine has been show to be effective in some cats, although its long term efficacy has not been proven yet in a large number of cats. The same holds true for Detemir. More studies with a large number of diabetic cats over a long period of time are needed.

  • PZI (Protamine Zinc Insulin)- Long acting

    This is one of the more commonly used insulins in cats. It is usually given every 12 hours. We start with a dose of 1-3 units, and adjust as needed.

  • Vetsulin (Lente)- Intermediate acting

    This insulin is approved for use in dogs and cats, and is one of the more common ones used, especially in dogs. Its use in cats is increasing due to good results. It is made from purified porcine insulin which has the same amino acids as canine insulin. Because of this there should be more effective regulation of blood glucose with less risk of anti-insulin antibodies. It is an intermediate acting insulin, and in some dogs once daily dosing is adequate. Cats usually need to be given their injections twice each day.

  • NPH (Neutral Protamine Hadedorn)- Intermediate acting

    This has been the mainstay for treating diabetic dogs over many decades. It is still used, although we have been using Vetsulin much more frequently. It is not used in cats.

Ketoacidotic Diabetes Mellitus

Pets presented with DKA need immediate medical attention. They need regular insulin due to its ability to rapidly lower the blood glucose level. They also need fluids and electrolytes to correct dehydration, electrolyte imbalance, and acidosis (a change in the pH of the bloodstream). If this therapy is initiated too aggressively it might cause more harm than good. Our goal is to return your cat to a relatively stable state within the first 1-2 days after initiating this therapy.

Regulation

Diabetic pets need to be slowly  regulated (the correct dose of insulin needed). Many pets will take 4-8 weeks to find the proper level of insulin Most cats have well entrenched pathology that is not conducive to rapid change. The dose has to be given in small amounts initially to prevent hypoglycemia. It takes several days for a cat to respond to a change in dose. This initial regulation only gives us a starting point for your pet’s insulin dose since there will be numerous mitigating factors that will affect insulin levels when your cat returns home.

Initially we will use a low dose and have you administer the insulin at home at this dose for the next 7 days. After 7 days we will perform a glucose curve in our hospital over 10 hours.  The blood glucose curve will give us an idea of how it is reacting to the type and amount of insulin we are using. Every pet is different, so this trending is needed to understand specifically how your pet will react. This curve will give us an accurate picture of just how high and how low the blood glucose is. This will then allow us to further refine the dose of insulin. We will do this glucose curve every 7 days, refining the dose each time, until we have achieved are desired level.

Any other problem your pet has, especially UTI’s (urinary tract infections) needs to be corrected for insulin injections to lower the blood glucose properly.

Our goal is to get the blood sugar level down to somewhere between 100-250 mg/dl. Some pets are regulated fine even if the blood glucose peaks at greater than 250 mg/dl. It is much better to have a pet that has a slightly high blood glucose level than to try and refine the dose so closely that hypoglycemia is risked.

To monitor your pets blood glucose we take frequent samples. To prevent the constant irritation from obtaining this blood sample we put a catheter into one of your cat’s veins. This eliminates discomfort and also minimizes the stress response.

This cat has jugular catheter — to learn more about catheters click here

 

The first step in the process of running a blood glucose test in our hospital involves taking blood from your pet and putting it on a special strip.

This cat’s blood glucose reading is 63 mg/dl. It is hypoglycemic at this point.

The typical pet eventually needs anywhere from 2-10 units given from once to twice daily. Of course this dose depends on the weight of your pet, the type of insulin used, its diet, its exercise level, and its individual response.

Even though these blood glucose checks are critical, your input as to how well your pet is eating, acting, and how much it is drinking and urinating, are just as important. If your pet is doing well in all these parameters then the blood glucose is being regulated.

Insulin Injections

It is imperative that you administer the precise amount of insulin required since small changes can have dramatic effects. Be consistent and give the insulin the same time and at the same location every day. If your pet is on twice daily insulin injections give each morning and evening dose at the same time every day. Always feed your pet in the morning prior to giving the insulin. If it does not eat its food skip the morning dose of insulin. If it eats only half of its food, give it only half of its insulin dose. Giving a normal dose of insulin to a pet that is not eating greatly increases the risk of hypoglycemia. You must always err on the side of hyperglycemia instead of hypoglycemia.

Most cats eat small bites of their food throughout the day. This might or might not work in a diabetic cat because of the manner in which the insulin that is administered peaks. If it does not work, feed your cat twice each day, feeding part of its daily meal when you give the insulin in the morning. Make sure it has access to this same food when the insulin level is peaking later in the day.

A record should be kept of your pet’s food intake to note any changes. The same thing holds for its water consumption. Marking this on a calendar weekly will give you important trends and give you a good idea if you are on the proper dose of insulin.

The actual administration of insulin is very straightforward. As a matter of fact, it is easier to give insulin injections at home than it is to give SQ (subcutaneous) fluids to cats that have chronic renal failure, a common feline problem. This is because an insulin injection takes 1 second to give, whereas fluids take 5-10 minutes. The technique used to give insulin injections or SQ fluids is the same- click here to view an actual demonstration of the administration of SQ fluids. When you are finished learning the proper technique return here to finish.

You will never be forced into doing something that makes you feel uncomfortable. While your cat is in the hospital with us you can observe how we give the insulin injections. One of our nurses will demonstrate its proper administration when we release your pet from the hospital. You can return to our hospital for assistance in giving the insulin at any time.

In order to simplify the process we will give you an insulin syringe that has been designed to be used with the specific type of insulin your pet requires. You will be giving insulin in a measurement called “units”, and not in ml (milliliters) or cc (cubic centimeters) as is commonly used in most syringes.

 

The use of injections is very simple. If we are using U-40 insulin, then we use a U-40 syringe. If we prescribe 2 units of insulin, draw up the insulin to the 2 mark on the syringe and give the injection. That’s all there is- no calculations are needed on your part.

Some cats require such a low dose of insulin that we have to dilute it for proper administration. A special diluent is needed for this, and diluted insulin should not be used longer than 2 months. A special syringe is sometimes used for dilute insulin.

This is what a U-100 syringe looks like. The needle is very small and sharp so your pet will not feel it during its injection.

Insulin should be kept refrigerated at all times to preserve its freshness. When you purchase it at the pharmacy bring an ice pack with you. Prior to use it should be gently warmed in your hands.  Storing the insulin bottle on its side in the refrigerator will help in mixing.

Gently roll it (never shake it vigorously because excess bubbles will form) between your hands for 1-2 minutes to bring it to the proper temperature for administration.

Make sure you are in a relatively calm location when you give the injection. Hold the insulin bottle upside down and draw out slightly more than the number of units your cat requires. Tap the syringe a few times to remove any air bubbles-this aids in accuracy (a few tiny bubbles are OK). Push the plunger in the syringe slightly forward until you have the exact number of units you need to administer is in the syringe. Put the cap back on the syringe and put the insulin bottle back in the refrigerator. Do not reuse the syringe.

We will show you exactly how to do this in person, and give the first few injections for you until you get your confidence. In this picture you can see we have drawn 6 units into the syringe.

Give the injection in the scruff of the neck just as you would when giving SQ fluids described above. Your pet should not feel anything because the needle is so tiny and sharp. The whole process, from warming the insulin to giving the injections, should only take a couple of minutes. As you get confidence it is recommended to rotate your injection sites. We can shave a section of hair to make this whole process easier.

Improper administration of insulin is one of the most common causes for improper regulation. Please do not hesitate to contact us at any time for assistance in this vital procedure. Unless unavailable, only one person per household should be delegated to giving insulin.

Home Monitoring

The best way to monitor your pets blood glucose at home is to perform the blood glucose yourself. Ears and pads are areas in which a small prick will give sufficient amount of blood to run an in home blood glucose. In some cats this method of obtaining a blood glucose level is preferable to running a glucose curve in the hospital. This is because the stress of the car ride and the obtaining of blood several times while in the hospital can mislead us as to your cats actual blood glucose level.

Some of our clients use a home glucose kit to check their cats. It is easy to do once we show you, and gives a more accurate assessment of blood glucose levels at home than does the glucose in the urine. You only need a few drops of blood for the glucometer.

To use the glucometer you need to find an ear vein. You can see this one running horizontally under our nurses finger.

It is very simple to prick the ear with this machine and get your sample

 After you place a drop of the blood in the green tip the machine will give you a blood glucose reading in a few seconds

Most people prefer to monitor the glucose in their pet’s urine because it is simpler. Monitoring of the glucose in your pets urine will give you at best a rough idea of its blood glucose level. There are significant limitations to home monitoring using urine glucose as a criteria. We do not recommend it.

Urine glucose measurements do not necessarily correlate with blood glucose measurements, the more important of the two. Also, if the blood glucose level is below the renal threshold a negative glucose in the urine cannot differentiate between euglycemia and hypoglycemia. If you note a significant amount of glycosuria consistently for several days your pet needs a blood glucose curve.

One of the ways the urine dipstick can be particularly helpful is in monitoring ketones. Occasional trace ketones is no cause for alarm. Consistent ketonuria in a cat that is not feeling well requires immediate veterinary care.

To help in the urine monitoring process your cat’s normal litter can be replaced with special litter that will not absorb urine. You can also use regular paper, newspaper, or even plastic wrap in the bottom of the cage. There is even a special litter that reacts with the glucose in the urine.

One of the more common urine dipstick kits is the Keto-Diastix. In addition to monitoring glucose it also monitors for ketones.

This is the chart on the Keto-Diastix bottle. The box to the far left is negative, which is the goal. The next box to the right is 100 mg/dl. Its OK to have this urine glucose value on occasion.

On the same bottle there is a chart to monitor for ketones in the urine. Your goal is to have negative with an occasional trace.

What is just as important as urine glucose is your subjective interpretation of how your pet is doing. If the original symptoms are greatly reduced then you are probably giving an accurate dose.

Determining the daily dose of insulin required at home is not an easy task. We have learned over the years that blood glucose determinations are variable, and that in many cases it is your perception at how well you pet is eating, how active it is, and how its drinking and urinating has decreased that is more important.

A more accurate blood test is the fructosamine level, which gives us an average of your pets blood glucose levels of the last 2-3 weeks, and is much less variable than individual blood glucose determinations. The fructosamine test is obtained at our hospital, and should be performed every 3 months after initial regulation.

Do not make any changes in insulin dose unless you talk with one of our doctors. Do not make daily changes in insulin doses either, wait 3 days to determine if the new dose is having any effect.

Warning signs that necessitate an exam and blood glucose curve in the hospital:

  • Lethargy or significant increase or decrease in appetite
  • Significant increase in drinking or urinating
  • (100 mg/dl) or more glycosuria for > 2 days
  • Significant ketones in urine for > 2 days

Long Term Care

It must be understood that in most cases insulin administration does not cure diabetes mellitus, it only controls it.  As you learned above in the physiology section, the body has very sophisticated and refined mechanisms to keep the blood glucose at optimum levels. This can not be replicated easily by giving insulin. The exception to this is the occasional cat diagnosed early in the disease process and is not overweight.  Glargine seems to be the best insulin to increase the chance of remission .

To minimize problems we should monitor your pets’s blood glucose level in the hospital and perform a urinalysis every 3 months. Since cats can exhibit an exaggerated stress response causing a profound hyperglycemia, a glucose curve is necessary to ensure accuracy. Every 6 months we should also perform a complete blood panel to look for changes in other organs caused by the diabetes. A urinalysis at the same time is needed to monitor for a UTI (urinary tract infection).

A further reason to run a complete blood panel every 6 months is to monitor routine age related changes like hyperthyroidism and kidney disease. Diabetes can also predispose your pet to high blood pressure (hypertension).

This long term monitoring is important for another reason. In almost every diabetic pet insulin requirements change, necessitating the need for close monitoring and communication with us. If your pet goes into heat (another reason to spay females and even neuter males) its insulin requirements might change. In some diabetic cats the problem goes away and they no longer have a need for insulin. Giving insulin to these cats can cause hypoglycemia, which if it is severe enough, can lead to seizures.

Complications of Diabetes

  • Hypoglycemia

    One of the more alarming, yet relatively rare side effects to insulin administration, is hypoglycemia. You should be ever vigilant about its appearance and always be ready to treat it at home. Close observation of your pets appetite will go a long way towards preventing this problem.

    Symptoms include shaking, a starry eyed appearance, lethargy, shaking, greatly enlarged pupils, muscle tremors and even seizures. If the problem is serious and persists long enough, coma and even death can occur from depression of the respiratory system. Some pets don’t show any obvious symptoms except subtle behavior changes like sleeping more than usual. Since cats sleep most of the time anyway this can easily be missed.

    In most cases the cause is an overdose of insulin. A common scenario involves a pet that eats significantly less than its normal amount for the day. Hypoglycemia can result if the dose of insulin is not adjusted to take this into account. If your pet is not eating well and you are unsure of its appetite, either give less insulin that day or do not give any at all. A blood glucose test in the hospital will let us know for sure.

    Other causes of hypoglycemia include improper insulin administration resulting in an accidental overdose, along with cats that spontaneously recover from their diabetes and no longer need insulin. This is why close monitoring of the blood sugar level is important, either at home or at our office.

    If the symptoms of hypoglycemia are mild, feed your pet some of its normal food. For many pets this will suffice. If the problem is severe use Karo syrup, a simple carbohydrate. It is readily available at the supermarket and should be kept on hand at all times. Give it in small amounts or rub it on the gums. Pancake syrup, honey, sugar water or any fluid that has high amounts of sugar can be used also. These high carbohydrate remedies only last a short time so you might have to keep on repeating one of them. Also, it is a good idea to have a source of simple carbohydrates in your car or other important locations when traveling or even just going for a walk. It pays to be prepared.

    In the rare case that your pet has a seizure or seems comatose from hypoglycemia, it is imperative that you do not put anything into its mouth, including your fingers.  These pets need to be seen by a veterinarian immediately.

  • Liver Disease

    Cats with diabetes are forced into using an energy source that will eventually cause a fatty infiltration of liver cells. As a result the liver will not function at optimum capacity, a potentially serious problem since the liver is such a vital organ. The liver enzyme test on the blood panel will alert us to this complication. When the diabetes is treated this problem might resolve. Radiography might reveal an enlarged liver (hepatomegaly) due to the fatty infiltration.

    This liver is larger than normal-it is extending towards the right far beyond the margin of the ribs. The 4 white arrows on the bottom outline the lower edge of the wedge shaped and enlarged liver.

    One of the most important disease syndromes associated with a fatty liver is called hepatic lipidosis. It occurs in overweight cats that are exposed to a stress that causes them to stop eating. This lack of appetite can become so severe that a feeding tube needs to be put in.

    Keeping the blood glucose level as close to euglycemia as possible will help minimize this complication. Again, the need for periodic blood glucose monitoring along with a routine blood panel every 3-6 months become obvious.

  • Somogyi Effect (Insulin Induced Hyperglycemia)

    Overdosing the morning dose of insulin can cause hypoglycemia. If the hypoglycemia becomes severe enough (< 60 mg/dl) the body will go through complex compensatory mechanisms to raise the blood glucose level. These mechanisms involve the liver, glucagon and epinephrine. If these mechanisms are unable to raise the blood glucose rapidly enough then the symptoms of hypoglycemia described above might occur.

    When these mechanisms are able to correct the hypoglycemia they can cause the blood glucose level to go quite high later in the day and persist through the night. If the urine glucose is measured just before the morning dose the next day there will be significant glycosuria due to the previous afternoon and evenings hyperglycemia. This will cause many people to increase the insulin amount in the morning dose. This overdosing will again cause hypoglycemia some time during the day, and the cycle will repeat itself.

    This problem is diagnosed by a blood glucose curve in the hospital. A cat with the Somogyi effect will have a blood glucose level that is abnormally low some time during the day. This emphasizes the need for a blood glucose curve to monitor your pet’s problem because only one blood glucose test during the day might miss the hypoglycemia episode that is causing this problem in the first place.

    Insulin antagonism

    Pets that are not regulated in spite of higher than normal insulin doses might have this problem. This problem can mimic improper storage, handling, and administration of insulin.

    There can be many causes to insulin antagonism. Hormones, cortisone, the Somogyi effect, adrenal gland disease, infection, chronic pancreatitis, kidney disease, cancer, anti-insulin antibodies, and even ineffective insulin all could be involved. Cats that get Feline Acromegaly, an excess of growth hormone, can also get insulin resistance.

  • Infections

    Diabetic pets are prone to infections, especially of the urinary tract. These infections makes them more prone to DKA and insulin antagonism. Good dental hygiene is critical also since many pets with diabetes have dental disease. Chronic dental disease can make regulation almost impossible.

  • Cataracts

    Almost all dogs with diabetes mellitus will eventually develop cataracts. The earlier the diagnosis is made the greater chance your dog’s blood glucose can be regulated to stave this off. One of our doctors might refer you to a veterinary ophthalmologist because there can be inflammation associated with this called uveitis. The cataract needs to be removed in this case to prevent pain and further complications. Your dog has to be properly regulated regarding insulin levels before the ophthalmologist can do this surgery.

Boarding a Pet with Diabetes

It is always preferable to keep your diabetic pet in its normal environment. When this is not feasible special precautions need to be taken if your pet is boarded. Cats that board away from home are at an increased risk of becoming unregulated as to their correct insulin amount. They will frequently have a diminished appetite, increasing their chance of hypoglycemia if their insulin dose is not adjusted. Your cat should be boarded only at a facility that is adept at treating this disease and can run a blood glucose curve in case of a problem. One of the more common reasons we board pets at our hospital is because they need this type of medical monitoring for their problem.

A fructosamine test should be performed just prior to boarding for us to get an accurate idea of your pets average blood glucose level.

You should bring your food and your insulin to the boarding facility. A feeding schedule with amounts of food and water consumed and at what times should be provided. Also include a timetable when insulin is given and at what amount.

Since diabetic pets should be monitored with a blood glucose curve periodically this is an ideal time to run this test. Many cats will adapt to their new environment in a short time, which should make their individual blood glucose tests more reliable. When your return to pick up your pet we will review this curve with you and adjust doses as needed.

Summary

It is obvious that this is a complex disease that requires diligence on your part for proper control. Since every pet is different, your doctor will make a custom plan that will work for you and your pet, and will not necessarily follow any pre-established protocol. Be prepared for constantly changing insulin requirements and potential complications. The more consistent you are with feeding the same food, in the same amount, at the same time(s) every day, will add to a successful outcome.

The majority of diabetic pets on insulin therapy have a significantly increased quality of life. This usually makes the time time and monetary commitment necessary for proper regulation well worth the effort.

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Allergic Dermatitis

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Allergies are a common cause of skin conditions in dogs and cats, along with other species. This type of allergy goes by several names; the most common are atopy, allergic skin disease, or allergic inhalant dermatitis (AID).

The main difference between us and pets is that allergies in pets tend to cause skin conditions, as opposed to the  runny eyes, runny noses, and sneezing we encounter in people. Symptoms typically include scratching and itching, although many other skin conditions can cause itching. Medically, this itching is called pruritus.

Allergies can be hard to control and are chronic in nature. This causes significant frustration for pet owners and discomfort for pets. A correct diagnosis, along with proper therapy instituted early in the course of the disease, will minimize this frustration. Many pet stores and groomers will give advice on a “food” to feed to cure your pet’s skin condition. It is irresponsible for them to be giving any advice of this nature due to the numerous causes of skin conditions, let alone the complexity of this disease, and also the fact they have not examined your pet and do not have any important physical information about your pet. We have a short page on Nutrition Advice that addresses this issue of people giving medical advice when they have no business doing so.

This page summarizes and generalizes the complex problem know as allergic skin disease. It is detailed, and will take a few minutes of your undivided attention to help in understanding this problem.

In the beginning of this page we will give you the background of their causes and how we diagnosis them. We will take about treatment towards the end.

Pathophysiology of Allergies

When the immune system encounters an allergen that has the potential to cause disease (ex. parvo virus) it produces antibodies called IgG (immunoglobulin G, previously known as gammaglobulin) and IgM (immunoglobulin M). For the first 7-14 days of infection the virus spreads throughout the body because not enough antibodies are produced to stop them. Within 7-14 days enough antibodies are made to neutralize the virus, and the pet eventually recovers from the disease, all other things being equal.

As time goes on, the now sensitized immune system is ready to produce large amounts of antibodies rapidly the next time it encounters this virus. The rapid antibody response neutralizes the virus immediately, instead of taking the 7-14 days that occurs the first time it encountered the virus. This is called the anamnestic response, and is why a pet that recovers from parvo virus does not get the disease again.

A different scenario presents itself when the immune system encounters an allergen that is not necessarily pathogenic (ex.- a pollen particle). A different part of the immune system kicks into high gear when these non pathogenic allergens invade the body.

When a pollen particle enters the body for the first time (through the skin or respiratory passage) it stimulates the body to produce antibodies also, this time they are called IgE (immunoglobulin E). This IgE antibody attaches to the allergen in order to neutralize it, just like IgG would do to a parvo virus. This process, called sensitization, occurs in the first season a pet encounters a specific allergen in its area. Without this sensitization there is no allergy. This type of allergy is the most common type, and is called atopy or atopic dermatitis.

The next time a pet encounters these pollen particles (usually the next allergy season), the immune system produces large amounts of IgE antibodies rapidly because it has been sensitized to them from the previous season. Again, this is similar to what happens when the immune system makes IgG and IgM antibodies against parvo virus.

IgE, with attached allergens, circulates throughout the bloodstream to a type of cell called the mast cell. Mast cells contain many chemicals that can cause inflammation, the most important of which, in relation to allergies, is called histamine. When an IgE antibody (even IgG can be involved) with an attached allergen encounters a mast cell under the skin, it alters the membrane of the cell, and histamine leaks into the surrounding tissue. Histamine causes inflammation, noted as redness (erythema) and itching (pruritus) on the skin surface. The reaction that is seen on the skin surface is called a wheal or a hive. This causes your pet to lick, scratch, or bite at this area which now itches.

It is the mast cell, that releases histamine when it encounters an IgE antibody with a pollen particle attached, that is a major component of allergies. This is what occurs in atopy and is suspected to occur in food allergy. In flea allergies, it is an allergic reaction to the flea saliva that causes the immune system reaction.

Other immune mediators are impliacated in atopy. They include cytokines, neuropeptides, peptides, proteases, and leukotrienes. They can affect nerve fibers to the skin, causing itchiness.

As if that is not enough, there are other immune mediators called Interleukin 31 (IL-31) that are involved. It’s an understatement to say that the immune system is very complicated. Add the ever present skin bacteria to this equation and it is easy to see how this can become a frustrating problem.

Food allergies have a slightly different pathophysiolgy then atopy in some cases. In food allergies, the offending allergen (usually a protein) is absorbed through the lining of the small intestines and proceeds right into the bloodstream.  This causes a different immune system reaction. If the intestines are inflamed from some other disease process, for example IBD (inflammatory bowel disease) in cats, the normal barrier lining the intestines is compromised and more allergens can enter the bloodstream.

Types

There are 3 main types of allergies in relation to skin conditions. It is possible for a pet to have a combination of all 3 allergy types:

Flea Allergy Dermatitis (FAD)

This is a very common cause of skin allergies, even if you do not see a flea on your pet. When a flea bites a dog or cat it is looking for a meal of blood in which to nourish itself. In order to suck this blood it inserts an anticoagulant into its saliva to prevent the blood from clotting while it sucks it through its small proboscis. It is the allergens in this saliva that cause an allergic reaction to occur.With the advent of new treatments that are convenient and very effective, this problem, while still important, has diminished in importance. The products we recommend are oral Nexgard, Comfortis or Trifexis in dogs and topical Revolution in cats. In addition to excellent flea control these products also prevent heartworms and internal parasites like Roundworms. Revolution in cats even controls mites. Our staff has detailed information to give you on these products along with others to help you make the right decision for your circumstances.Since we live in a flea infested area we recommend using these monthly flea products year round. They have the added advantage of worming your pet every month for Roundworms, Hookworms, and Whipworms.Fleas are a common cause of skin allergies in cats.

Atopy or Allergic Inhaled Dermatitis

Another common cause of skin allergy is atopy. It is a genetically determined predisposition to produce IgE antibodies when exposed to an allergen. Re-exposure to this same allergen in the future causes allergic skin disease (you learned the mechanism above). Depending on the study, it is estimated that between 3% and 15% of dogs have atopy.Common allergens that cause this reaction are ragweed, pollen, house dust, house dust mites, mold, animal dander, feathers inside the house. Outside its grasses, trees, and shrubs. The allergens can be inhaled, pass through the pads of the feet, and even possibly ingested. Since these compounds are in abundance everywhere, it is apparent that preventing exposure in the first place is difficult.If fleas are not a factor, atopy accounts for up to 90% of the allergies that cause allergic dermatitis.  A certain number of pets with atopy also have a food allergy concurrently, which compounds the diagnosis and treatment.

Food Allergy

The least common cause of skin allergies is food allergy, although pets stores and groomers are under the impression that this is the sole and most important cause of skin allergy, which is why they give amateur advice on what to feed. They are in the business of selling food, which is why they only see food as a solution to atopy, when it is the least common cause.  Our page on Nutrition Advice has much more information on this topic.

It is important to distinguish food intolerance from an actual food allergy. They are not the same, but many people giving amateur advice on this problem do not understand the difference.

In the vast majority of cases, food allergies are caused by an allergic reaction to proteins in food. The size of the protein particle is important. They have a molecular weight of between 18 and 70 kilidaltons (kD). In laymens terms, they are very, very tiny.

Heredity is a major predisposing factor in people, and probably so in animals.

Some of the more common food allergens in dogs and cats are:

horse meat eggs
beef fish
pork corn
lamb soy
chicken wheat
dairy products rawhide chews and dog biscuits/treats

In dogs, beef, dairy products, and wheat tend to cause most of the problems, with chicken, lamb, and soy following. In cats, beef, dairy products, and fish account for most of the food allergies. Premium dogs foods can contain these products, so just because you are feeding a higher quality or more expensive food doesn’t mean that food will not cause a food allergy.

Many pet stores are there to sell food, so they will tell you a certain type or brand of food will cure your pet’s skin (and other) conditions. The employees of these stores have no business giving their advice unless they are licensed nutritionists for animals, or are licensed veterinarians,  and have discussed with you the following points that are so important in making a diagnosis of any disease, including allergic dermatitis:

      • Your pet’s predisposition to certain diseases, including allergies
      • Your lifestyle and your pet’s lifestyle
      • The specific history of your pet’s skin condition- time of year, where they are itching, etc.
      • Results of a thorough physical exam checking all organs besides skin
      • Routine blood panel to assess the status of your pets internal organs along with protein levels, blood glucose, electrolytes, red blood cells, and white blood cells.
      • Your pet’s vaccine status
      • Diagnostic tests to eliminate internal (hormonal etc.) and external (mites for example) causes of skin conditions.
      • The efficacy of prior treatments
      • The effects a change in diet will have on other organs besides the skin

Most of the symptoms of food allergy involve inflammation and scratching of skin or ears, but might also include vomiting or diarrhea. These gastrointestinal symptoms tend to occur more in cats.

In those pets that truly have food allergy, a high percentage also have atopy at the same time. Cats might have more food allergies than dogs, although fleas are a common cause of skin allergy in cats.

Symptoms

The most consistent symptom in pets with allergic skin disease is excessive itching. The medical term for this is pruritus. High strung dogs might itch more than placid dogs. Chewing, biting, or licking, or rubbing the skin can all be manifestations of pruritus.

Dogs can chew so incessantly that they wear down their incisor teeth to the gumline

In dogs some of the more common areas for pruritus to occur are the face, feet, and armpit areas. As the problem progresses the whole body might be involved. Some pets will scratch excessively but not show any problems with their skin.

If your pet has an allergy to fleas you might find tiny blood spots where it has layed down. These are the result of flea dirt that has fallen off your pet and become wet. Since flea dirt is made up mostly of blood that the flea has sucked out of your pet and has passed through its digestive tract, they appear as small blood spots on the floor or table tops when wet.

Other symptoms can include:

The slight redness (erythema) to the face of this dog

The dark, stained areas on this poodle’s foot are due to excessive licking. The color change is due to the chronic saliva on the hair, and the changes it causes on the hair coat.

This dog’s skin is oily from chronic rubbing. This loss of hair is called alopecia.

This Golden Retriever has significant redness (erythema) on its ear flaps. Chronic ear inflammation or infections can be a sign of atopy or a food allergy.

The above pictures were all caused by atopy. They could have been caused by other diseases though, so you cannot make a diagnosis of a skin condition just by looking at them.

Cats get skin allergies also, although not as frequent as in dogs. They might exhibit the same or different symptoms. Different symptoms include tiny bumps throughout the body, ulcers on the lips, excoriation of the neck, and even patches of missing hair (alopecia) without any skin lesions. Ear problems related to allergies are rare in cats compared to dogs. Cats get a problem called psychogenic alopecia that can be similar in appearance to atopy.

It can be difficult to tell pruritus from normal feline grooming. Vomiting hair balls, hair in feces, and hair in your cat’s mouth when you brush its teeth (you are doing this aren’t you?) are all clues.

This cat has an allergy that caused it to irritate the skin above its eye by rubbing its face

This is a severe version of an ulcer on the lips. It is called the Eosinophilic Granuloma Complex, and sometimes known as rodent ulcer.

Diagnosis

Since the symptoms of allergic skin disease mimic those of other skin diseases, a thorough approach is needed to differentiate them. In every disease we encounter we follow the tenets of the “diagnostic process” to ensure that we make an accurate diagnosis, and that we do not overlook some of the diseases that are also encountered in conjunction with skin diseases.

It is too easy to jump to the conclusion as to what is causing your pet’s pruritus. Here is a list of  possible causes of scratching and itching in pets in random order:

  • Atopy
  • Drug reaction
  • Flea allergy dermatitis
  • Food allergy
  • Lice
  • Autoimmune disease
  • Pyoderma
  • Contact Dermatitis
  • Viral infection
  • Fungal infection (Malassezia)
  • Mites
  • Seborrhea

Signalment

Typically, atopy occurs in mature dogs between 1- 3 years of age, although it can occur earlier (Shar pei’s can get it as early as 3 months). The condition rarely starts in dogs over 6 years of age. Most dogs get their first exposure to an allergen and develop sensitization in their first exposure to a pollen season.

Symptoms usually occur during their second season of exposure to the pollen allergen when the immune system has its exaggerated response to the allergen and produces high levels of IgE. Dogs that are highly allergic can show signs of atopy during their first season of exposure to pollen allergens. It depends on how long the pollen season lasts and how rapidly their body produces the IgE antibodies.Several canine breeds are prone to getting atopy. They include, but are not limited to:

Terriers Beagle
Retrievers Setters
Lhasa apso Miniature schnauzer
Shih Tzu Pug
Cocker spaniel Boxer
Dalmatian Shar Pei

History

Atopy, in it’s initial stage, tends to be a seasonal problem. This can be a help in differentiating it from food allergy, which would be a non-seasonal problem. Atopy tends to be a progressive disease with worse symptoms each allergy season. Many dogs will be more affected during a specific season. As time goes on dogs can have allergies year round. It is not a contagious disease, so other dogs, cats, and people in the same household do not usually have symptoms (unless of course it is another dog that is highly prone to allergies).

The progeny of atopic dogs are more prone to developing atopy than other dogs. Careful breeding therefore can help minimize the occurrence of this problem. Pets that have been treated with cortisone in the past, and did not improve, give us a clue that something else besides an allergic disease is involved. Food allergies in dogs and cats can start at any time in a pet’s life, even those on the same diet for a long period of time. Non-seasonal allergies bring food allergies to mind, along with vomiting or diarrhea, although these are not consistent findings. The skin lesions in food allergy are indistinguishable from atopy, but have a propensity to show only inflammation of the ears.

Feeding dog and cat foods that contain ingredients that pets are routinely allergic to might also clue us in to a food allergy. This includes the premium foods and those that contain lamb. Flea allergies are suspected whenever we are presented with a pet that has a skin condition, especially towards the back end,  and is not on routine flea control. This is true even for pets that never go outside. Other pets in the household that are itching might also indicate fleas in the environment. Flea allergies routinely cause hair loss at the lower back area (called the dorsal-lumbar area), which is not typical of atopy and food allergy.

Physical Exam

The physical exam of a dog with a skin condition is the same as any other sick pet. We examine the whole body for clues as to the cause of the skin condition. The distribution of the skin lesions gives us a clue as to the cause, but is not consistent in all skin conditions. Some of the more common exam findings are:

Pyoderma

This dog has licked so much it has maimed itself, and now has pyoderma, which is a skin infection, typically a Staph (usually staphylococcus pseudointermedius) infection

Conjunctivitis

This is an inflammation of the eyes. The green discharge in the corner of the eye is from fluorescein stain that was checking for a scratch on the cornea.

Lichenification and hyperpigmentation

Chronic licking and scratching can cause thickening and dark pigmentation of the skin. The white arrow points to mild hair loss, hyperpigmentation, and lichenification in a Yorkie.

Acute Moist Dermatitis

Commonly know as a hot spot, it is an area of skin that has been maimed from intense pruritus. Pyoderma is also present, and the skin is very painful. Hot spots occur rapidly and can encompass a large section of skin in a short time. Affected areas usually include the rump and the side of the face. Other common causes of hot spots include anal gland problems, ectoparasites like mange, grooming, and deep skin infections. Golden and Labrador retrievers, St. Bernards, Collies, and German shepherds are more prone than other breeds.

The serum that is exuded from the inflamed skin matts the hair and causes the problem to progress under the hair coat without anyone realizing how serious it is. These pets can be so painful that we need to sedate them prior to clipping the hair and cleaning the wound.

Hot spots can progress and cause serious skin conditions. What looks like a minor skin wound with matted hair can actually be a serious and painful infection.

Once the hair is shaved away the seriousness of the problem is apparent

Otitis externa

This is an infection of the outer ear canal. Sometimes this is the only symptom of allergy, especially food allergies. This ear is so severely infected that it is difficult to ascertain the normal anatomy. The ear canal is completely occluded, necessitating surgery to correct it. This dog is painful.

Pododermatitis

Infection of the feet can occur from chronic licking

Acral Lick Dermatitis

These are commonly known as lick granulomas. There are many causes, allergies being a primary one. Other causes include arthritis, skin tumors, inflamed nerves, fungal infections, ectoparasites, and psychological factors like boredom and stress. Once the licking starts the problem is difficult to control. In some cases we have found that the use of the laser has been a significant help. The most effective treatment is the use of antibiotics for many months.

This small lick granuloma is on the front leg of a Golden Retriever

Fleas or flea dirt

Flea dirt is literally droppings from the flea after is has bitten a pet and the blood has passed through the flea’s digestive tract. It looks like pepper, and is easily visualized on a pet with a white hair coat.

This is an example of lots of flea dirt

Flea eggs are small white particles, similar in size to flea dirt, that fleas lay in a pet’s hair coat. They eventually drop off and contaminate the environment. A pet can have fleas, yet show no evidence of fleas, flea dirt, or flea eggs.

Flea allergy dermatitis typically does not cause hair loss around the face, eyes, and ears like in atopy, although this is not a hard and fast rule.

Diagnostic Tests

Diagnostic tests are important even if we strongly suspect an allergy. In some situations other skin diseases can occur simultaneously with the allergy. It is impossible to make a diagnosis in any skin condition just by looking at it. This is because there are many diseases that affect the skin, yet the skin has only a limited number of ways to exhibit signs of disease.For food allergies we want to completely remove the offending protein and see if the problem (skin disease or GI signs) completely resolves. At that point we again feed the offending protein and see if the problem recurs. This is called a trial elimination diet, and is the only way to confirm a diagnosis of food allergy.The diagnosis of food allergy is not complete until we cause the allergy again by feeding the original food. This is because there are many allergens in the environment that can cause pruritus after the food allergy is controlled. Also, it is easy to assume the food allergy is under control when your pet is on medication simultaneously.

Skin Scraping

It is important to do a skin scraping in many cases of allergy because the lesions of atopy commonly mimic those of other diseases. Ectoparasites like demodex or scabies can cause skin lesions and itching.

Fungal Tests

Ringworm can mimic allergy symptoms. Lesions from Ringworm tend not to be as pruritic as allergies.

Malassezia, another fungus, is commonly associated as a secondary problem when the skin is infected. Even though it is a normal part of an animals hair coat, it will add to the itching if other conditions are present. Common areas for Malassezia include the ears, lips, muzzle, between the toes, and the anal area. Indications that Malassezia is present include pruritus, erythema, and greasy skin with an offensive odor. These symptoms can occur with other diseases besides Malassezia.

Malassezia is diagnosed by the above symptoms and by looking for the organism under the microscope after swabbing the skin and placing the discharge on a microscope slide. Many pets respond to shampooing with specific antifungal shampoos twice weekly. These topicals will only work when the underlying allergy and its associated skin infection are under control. In some cases we use oral antifungal medications to control the problem.

Thyroid Test

Hypothyroidism can cause skin conditions, although dogs with only hypothyroidism are not terribly pruritic.

Fecal Exam

Hypersensitivity to internal parasites can cause symptoms similar to atopy. This is not a common situation.

Skin Biopsy

In some cases it is difficult to make a diagnosis. When we are presented with this situation we will biopsy several small pieces of infected skin and have them analyzed by a veterinarian that specializes in tissue analysis of the skin.

Here is a typical report from one of them. All of the big words mean that in this skin biopsy an allergy is most likely, but autoimmune disease cannot be ruled out for sure.


Allergy Testing

Allergy tests are performed in cases where we already have a diagnosis of allergy. The main purpose of allergy testing is to find exactly what your pet is allergic to, and also to set up a protocol for allergy injections. If giving allergy shots is not contemplated then this test is of less value, although it will let us know what allergens we want to avoid. Trying to avoid these allergens though is the hard part because they are in our houses and almost everywhere outside.

There are two main types of allergy tests that are performed. Neither one is perfect, and they can have false positives and false negatives. They are not accurate in diagnosis a food allergy.

Intradermal (skin) Test

Most of us are familiar with the first one. In this test, called the allergy skin test or intradermal test, small amounts of materials that routinely cause allergies in dogs are injected under the skin. The reaction, if any, is graded, and a determination is made as to whether or not a pet is allergic to that specific allergen.

This test is very subjective, and therefore prone to errors in interpretation, and therefore requires significant experience. Many different techniques are used.

Your pet must be off of oral cortisone medication for at least 1 month before testing. If injectable cortisone is given, the waiting time is longer. Your pet must not be on any tranquilizers at the time of testing and must be off of any antihistamine medication for 10 days.

Pets usually are given a sedative to calm them and to minimize the release of cortisone due to stress, which will affect the outcome. The hair on the side is clipped where there is no current dermatitis occurring. A tiny amount of histamine is injected first. If there is no reaction to histamine, the full test is postponed. A small amount of sterile saline is also injected as a control.

The areas where the allergen is injected are marked

Numerous allergens are injected into the skin and a reaction is noted at 15 minutes and again at 30 minutes. The reaction we are looking for is called a wheal. A positive test to a specific allergen occurs when the reaction is in between the saline and histamine tests in size.

In some cases the wheal is obvious, in others it is subtle, which is part of the interpretation process

RAST (in vitro test)

The second type of test that is performed is called the RAST test. RAST stands for radioallergosorbent test. Another in vitro test is called the ELISA (enzyme linked immunosorbant assay) test. RAST tests for the levels of allergen specific IgE. In this test a blood sample is taken and submitted to a special lab for analysis.

The RAST test has advantages over the intradermal test. There is no clipping, sedating, and there is no potential to have an adverse reaction to an allergen injected into the skin. There is less of a chance that prior drug therapy (cortisone) will influence the outcome, and it can be used in patients that have dermatitis.

The primary disadvantage is the fact that false positives are more common when compared to the intradermal test

The RAST test is very thorough and checks for many different allergens in the home, outside, and in your pet’s food. Here is an example of one of their reports:

Here are 4 of the dozen household allergens they tested. This dog is borderline for orris root and human epithelial cells, and positive for jute/sissal and tobacco smoke.

These are a few of the food allergens tested in this sample. There was no allergy to venison, eggs, or milk, but this dog was allergic to soybean. This give us a rough idea of what food your pet might be allergic to, and can only be confirmed with the trial elimination diet.

This is a tiny sample of the numerous allergens found in the environment tested for on the same dog as above

Allergy tests can be unreliable at diagnosing food allergy. A better way to diagnose food allergies is using a technique called the elimination trial. By taking away a food that is suspected of causing the food allergy you can determine if the problem resolves. This might take up to several months to know for sure. To verify the diagnosis you need to feed the suspected food again to see if the skin condition returns. Commercial diets that contain rice, venison, fish, and potato are commonly used for the elimination trial. There is a food manufactured by Hills called Z/D that has been a big help in diagnosing and treating food allergies.

Routine Blood Panels

On occasion a specific type of white blood cell, called an eosinophil, is elevated in allergic conditions. Other conditions, notably worms, can also cause this elevation in eosinophils.

A routine blood panel can also give an indication of internal or hormonal problems that might show up as a skin condition. The most important of these are hypothyroidism and Cushing’s Disease.

This blood panel shows an elevated alkaline phosphatase level. This could be an indication of a hormonal problem called Cushing’s Disease.

Treatment

In the early years of atopy the pruritus is more easily controlled. As the problem progresses treatment is not as rewarding. Chronic changes to the skin can occur, especially lichenification and hyperpigmentation.

Treatment is aimed at all the factors that contribute to pruritus. For example, a pet that is normally not atopic might become so if exposed to fleas, or if it gets a pyoderma, or is allergic to a protein in its diet. This concept is called summation of effects, and might push the pet over what is called the pruritic threshold. By minimizing one of these components you might keep your pet under the pruritic threshold and minimize its skin or GI symptoms.

Food Allergy

Hypoallergenic means foods that your pet has never eaten, which technically, it cannot be allergic to. We recommend using these foods in some cases when we feel the pruritic threshold has been reached and any decrease in allergen load will put your put under this threshold. It might take up to 2 months to know if the food is working. You cannot feed any other foods or treats during this trial period, so plan on rewarding your pet with something else besides food.

There are 3 different diets to help:

    • Homemade
    • Commercial Novel Protein
    • Commercial Hydrolyzed Protein

Homemade diets can be beneficial, and have the advantage of controlling the protein and carbohydrates sources. It is important to pick a protein source your pet has never been exposed to. To be sure of this we sometimes need to resort to diets that contain some unusual ingredients.

Homemade diets have the substantial drawback of time, expense, guesswork, and being nutritionally incomplete. Some pets do not accept the food, and some of them develop diarrhea. For these reasons most pet owners do not use this treatment method.

Commercial Novel Protein Diets are a popular treatment for food allergies. Novel protein means your pet has never eaten this protein in the past.  For them to work, just like homemade diets, the protein source has to be a food your pet has never been exposed to, which can be difficult to determine. Traditionally they have contained fish, lamb, potato, or venison. Many pets react to several different proteins compounded the problem. Compared to homemade diets commercial diets have the advantage of being nutritionally complete and convenient. It is becoming more and more difficult to find a food that conatins a protein that is truly novel.

In many cases these foods work well to eliminate or decrease the food allergy. It takes up to 8 weeks to know if they are working, and your pet needs to be fed only these foods and nothing else, and be off all medications to decrease scratching. You might have to try different foods to find one that works for your pet. Unfortunately, its possible for some pets to eventually develop and allergy to one of the novel proteins in the food you are feeding.

Commercial Hydrolyzed Protein diets are the best option in most cases. The advent of these diets for food allergies has been a big step in eliminating the problem. Instead of trying to find a novel protein, these foods have literally decreased the size of the protein particle that gets absorbed in the intestines into the bloodstream. This reduced size is now too small to cause a food allergy, no matter what the protein source initially. These foods are nutritionally complete, convenient, and the ones we tend to recommend in most cases of food allergy. The brand we use most is Hill’s z/d. Hill’s was the first manufacturer to identify this solution and z/d is still the gold standard. This food is  unconditionally guaranteed and you will get your money back if you are not satisfied.

It is important that you do not have your pet on cortisone or antihistamines while trying to determine if your pet has a food allergy, since they will decrease the scratching and lead to an erroneous conclusion on the effect of the food. This causes a dilemma for those pets that have significant scratching, since they need immediate relief. In these cases we recommend using medication initially and starting your pet on a hypo-allergenic diet at the same time. If the itching is decreased after 1-2 months you can start weaning your pet off the medication to determine if the scratching is still diminished while on the hypo-allergenic diet also. In some cases we find the use of this food will allow us to use less medication to control the scratching.

Compliance is important, so make sure that everyone that even remotely feeds your pet knows about the diet change. If you give your pet food with medication, or treats, make sure it is not the original food that might have caused some allergy. Some pets need time to make the transition to a new food so be patient. Never let a cat go more than a few days without eating due to potential problem with the liver. Mix their new food in with their original food and make the transition over 7 days.

Avoidance

Obviously, if it is exposure to an allergen that causes the problem in the first place, then logic will dictate that we eliminate this exposure. In reality though, these allergens are everywhere. Minimizing exposure can be beneficial since it will decrease the allergen load, and hopefully keep your pet under the pruritic threshold.

Pets that are allergic to kapok, wool, cotton, feathers, animal dander, newspaper, and tobacco smoke all might benefit from limiting exposure. Limiting the number of houseplants could be helpful, and use synthetic material for your pets bedding. Pets allergic to house dust mites might do better kept out of bedrooms or placed outside more often.

Being outside though might expose them to more pollens. Grass is a common allergen causing skin allergy, so if possible, try to minimize exposure.  Keep the grass cut short, and keep pets out of the yard when cutting the grass. Rinse your pet’s feet and face off thoroughly after being exposed to grass can be beneficial in some cases.

Mold allergies might be helped by dusting and cleaning more thoroughly, especially house plants and bathroom carpets. Even think about replacing your carpets with wooden flooring. Keep your pet away from damp areas like basements (in California that’s easy since we don’t have many) and use humidifiers and air conditioners in humid weather. Rinse their filters frequently and clean with chlorine bleach. To truly filter most of the dust, mites, pollens, bacteria, and molds in your house you need to use a HEPA (high efficiency particulate air) filter. Upright vacuum cleaners return most of the dust back into the air, so use canister or cylindric type machines.

Routine and thorough washing, cleaning, and vacuuming of your household will keep mold, house dust, and house dust mites to a minimum. Keep your pet out of the house when doing thorough cleaning and vacuuming to minimize allergens that are stirred up by the cleaning. Put flea powder or a flea collar in the vacuum bag. Put plastic over bedding that might harbor house dust. Keep pets indoors at dusk and early morning during heavy pollen seasons.

Flea Control

Since we live in a flea endemic area year round, we cannot emphasize the importance of proper flea control in any pet that has a skin condition. Even pets that are 100% indoors are possible flea victims. This is especially important in cats, both indoor and outdoor cats.

The products available today are a significant improvement over flea control products in the recent past. They are economical, safe, effective, and very convenient. The product we recommend for dogs is Trifexis©. It prevents fleas, heart worms, and internal parasites, and is given orally instead of a topical gel.

The flea control product of choice for cats is called Revolution©. In addition to treating fleas, it treats heartwormear mites, and internal parasites (depending on the species).

Both of these products are used monthly. In some situations one of our doctors will have you use it more often. We also have detailed brochures on these products.

There are many  flea products that also can be used. Some are oral, some are topical, some are long lasting collars. Here are some of our recommendations:

Topical- Canine

Advantage Multi

Frontline Tritak

Vectra

         Oral- Canine

Comfortis

Nexgard

Sentinel

Trifexis

Bravecto

      Collar- Canine

Serestro

      Topical- Feline

Advantage II

Revolution

Vectra

       Oral- Feline

Comfortis

Bravecto

       Collar- Feline

Serestro

Medical Therapy

Every pet reacts differently to the medication used in atopy, so we might need to try different ones, at the lowest dose possible, to find the medication, or medications, that work best. Since treatment tends to be long term, so our goal is always to substatntially minimize the itching whilel using as little medication as possible. We use a multmodal approach, utilizing topicals, antibiotics, nutrition, and anti-inflammatories, to give the best possible outcome.

Cortisone

One of the mainstays of therapy for treating atopy is cortisone, commonly know as steroids. These steroids fit in the class of drugs called corticosteroids, which are not the same thing as anabolic steroids used by bodybuilders. Cortisone use is usually reserved for flare-ups, since long term use has the potential for causing side effects. Long term use of high doses of cortisone can lead to hair loss, thinning of the skin, liver problems, stomach problems, and muscle weakness. The overuse of cortisone can also cause iatrogenic Cushing’s disease.

Cortisone is a potent drug used in human and veterinary medicine literally thousands of times each day. Without this drug we would not be able to treat a large number of diseases. Cortisone has been abused by some people, leading to a bad name for this drug in some people’s minds. When used judiciously, and under a doctor’s supervision, it is one of the most important drugs we have. It is our first line of defense when a pet is scratching so severely it is maiming itself.

Cats are more resistant to the side effects of cortisone than dogs. Some cats are difficult to pill, so it is not uncommon to use an injectable version of cortisone that lasts for several  weeks to months. Older cats need to be checked for underlying problems like sugar diabetes and heart disease before instituting cortisone therapy. Cortisone will raise the blood sugar level, making it more difficult to control the problem. It can also cause the body to retain more sodium. This is only a problem in a cat that is in congestive heart failure.

Cortisone is usually given on an every other day basis and eventually decrease the dose even further as your pet improves. This minimizes side effects yet still gives an adequate amount of the drug to minimize scratching. In many cases we give an injection first to give your pet immediate relief from the scratching. We routinely use cortisone for 1-2 weeks to help get the scratching problem under control. Since cats are more tolerant to cortisone, and can be difficult to pill, it is not unusual to use the injectable version of cortisone in them.

While on cortisone you will notice that your pet drinks and urinates more than usual. It might also have an increased appetite and might show some behavioral changes. These symptoms will go away, in the meantime make sure your pet has access to fresh water at all times and can go outside to use the bathroom frequently.

Antihistamines

Antihistamines can be effective in treatment in some cases. They counteract the release of histamine (that’s why they are called antihistamines) from the mast cell, which as you know is the source of the itching. They are the mainstay of our long term medical treatment for skin allergies. Occasional side effects include drowsiness and dry mouth, both of which tend to resolve. In general, they are safe to use on a long term basis.

We will initiate an antihistamine trial to determine which one, if any, is most effective for your pet. We do a trial for up to 2 weeks to determine if one is effective or not. It is helpful not to have your pet on cortisone at the same time we are trying a new antihistamine, since we will not know if a decrease in pruritus is due the cortisone or the antihistamine. If we find one antihistamine that works well we stay with it on a long term basis. Eventually this might change, and if there is a significant flare up we will use cortisone to control the problem for several weeks. In the long run, even if antihistamine use has only minimal effects on decreasing pruritus, its use can help us decrease the use of cortisone.

Some of the common antihistamines we use are:

Benadryl A

Atarax

Tavist

Chlorphenaramine

Amitryptiline

Medications used to treat allergic dermatitis are used on a long term basis. We will refill medications as needed, and require a complete physical exam every 6 months to verify we are still treating the correct problem and to check for potential side effects to medication. A blood sample will be recommended periodically to verify the health of internal organs that might be affected by long term medication.

There is a combination antihistamine and cortisone called Temaril-P that has been use for decades. The two drugs in combination haven proven to be highly effective, and since each of these drugs is at a low dose side effects are rare.

Cortisone/Antihistamine Combination

A popular remedy we use commonly and successfully is called Temaril-P. The cortisone and antihistamine are in a low dose (trimeparizine -5 mg, prednisolone-2 mg), but when combined in the same medication have the effect of a larger dose. We get the best of both worlds in this case because the low amount of medication means less chance for side effects when used long term. This drug is also effective for pets that are coughing and vomiting.

Apoquel

Apoquel is a member of a class of drugs called Janus Kinase (JAK) inhibitors. It is an immune mediating drug that suppressed cytokine function. Cytokines are implicated in the cause of itchiness (pruritus).

A very small amount of dogs had diarrhea, vomiting, and excess drinking, which went away eventually.

It should  not be used in dogs with history of cancer (neoplasia), demodectic mange, or that have severe immunoseppresion. Its simultaneous use with cortisone (prednisone) has not been evaluated.

Apoquel has proven to be highly effective, and has been the treatment of choice in many cases of atopy.

Cytopoint

This is an injectable version of Apoquel that has also proven highly effective in controlling atopy. An injection lasts up to 2 months.

Antibiotics

Some dogs scratch so severely they cause a secondary bacterial infection of the skin called pyoderma. The bacteria that commonly causes this is called Staphylococcus intermedius or pseudointermedius.This secondary bacterial infection intensifies the itching. These dogs need treatment with antibiotics for several weeks to several months. In addition, they need to be bathed with shampoo that will help the skin infection. Long term use of antihistamines are not effective if a skin infection (pyoderma) is allowed to persist.

If a hot spot is present it will be gently clipped and cleansed. Pets with hot spots must be put on antibiotics and usually short term cortisone to prevent the problem from progressing. Hot spots are very painful, and oftentimes require sedation if the wound is to be clipped and cleansed properly.

Antibiotics that work best for pyoderma include:

  • Cephalexin
  • Baytril
  • Clavamox

There is a new version of injectible antibiotic called Convenia that lasts for 2 weeks. This is especially useful in cats due to the difficulty in giving them a pill.

Antifungals

Secondary fungal infections can occur, especially when the feet are licked constantly. The most common one is called Malassezia. It is treated with topical antifungals in most cases.

Cyclosporines

An effective long term treatment for atopy relies on cyclosporines, the medication that prevents organ transplant rejections. It is called Atopica© 

 Your dog must weigh at least 4 pounds for it to be used. Its main advantage is the fact it works without any side effects on a long term basis that can be encountered in drugs like cortisone.

It has recently been approved for us in cats in a liquid form

Atopica is highly effective, and we recommend it as one of our important long-term treatments for atopy. It does not contain cortisone so we do not have the side effects associated with cortisone.

Initially it is given once daily for 30 days, and should be given one hour prior or two hours after a meal. If a response is achieved we will decrease the dose slowly, with the ultimate goal of giving it 3X per week. It becomes cost effective at this twice per week dosing, and it is warranted to try this medication if your pet is on chronic cortisone use or you want an effective treatment without cortisone.

Allergy Shots

If an allergy test is performed on your pet we will know what it is allergic to, and allergy shots can be custom designed for your pets specific allergy. Giving allergy shots is called hyposensitization or immunotherapy. Theoretically, hyposensitization stimulates the production of IgG, which subsequently attaches to the allergen, preventing IgE from attaching to this same allergen. If there is no IgE attached to the allergen, then the mast cells do not release histamine.

Even if you do not give the allergy shots, knowing what your pet is allergic to can be beneficial in some cases, assuming you can remove the offending allergen (see previous section on avoidance). We tend to rely on allergy shots when avoidance methods and medication are unsatisfactory in minimizing pruritus. The company that performs the RAST test also supplies us with the allergens to give the allergy shots.

Giving allergy shots can be a significant way to minimize your pets scratching, although just like in people, no guarantee can be given to the outcome. Estimates vary, but in general, you can expect some improvement 60% of the time. In some cases we will still keep your pet on an antihistamine or cortisone, or Atopica©, but at a reduced dose. A decision to undertake this treatment modality takes a commitment to a lifetime of giving these injections in most cases.

Giving the injection is very easy since it is a small amount with a tiny needle. We will teach you how to give them, and if need be, will give them for you. Initially, the injections are given every few days for several months. It takes at least several months to know if the injections are working, and up to a year for full effectiveness. Eventually, they are only given from once every few weeks to only a few times per year. Each pet’s response is different.

Allergens are made specifically for each pet. This dog is allergic to many things, so three vials are needed to treat its problem.

Room Purifier

If your pet is kept in a confined area, the use of a room purifier that filters out pollen particles can be of big help.

Food Supplements

Some allergic dogs and cats scratch less when supplemented with essential fatty acids.  Essential fatty acids tend to work best when combined with an antihistamine. The main ones we use are Derm Caps and EFA-Z. As with other therapeutic options, essential fatty acids will not work when the skin has pyoderma. It will take at least several weeks of supplementation to see any improvement. In some cases the need for inflammatory medication will be reduced when a pet is put on essential fatty acids supplementation.


Bathing

Bathing in cool water several times per week is beneficial. Do not use hot water because it can intensify the itching. Proper bathing will help remove allergens and eliminate dry skin, both factors that affect the pruritic threshold. Bathing your pet too often will dry its skin out and increase its itchiness.

We have many different shampoos that will help you- please ask one of our receptionists to show you. We have had best results with oatmeal shampoos and rinses, along with antihistamine shampoos and rinses. Use a mild shampoo once weekly to keep the hair coat clean without drying it out. For hot spots we use Oxydex shampoo. If we suspect a secondary fungal infection caused by Malassezia we will use an antifungal shampoo called chlorhexidine.

This is an allergic reaction to shampoo in the arm pit area of a 8 month old female pit bull named Pumpernickel. This illustrates the principal that many things can cause an allergic reaction, even treatments for allergies.

Topical Medications

There is a strong tendency on the part of pet owners to use topical medications for allergic skin disease. They are used, and are helpful, but should not be relied upon as the primary source of treatment. Topical medications we use usually have an antibiotic, an antihistamine, or cortisone as ingredients. We tend to use topical agents most often when presented with pets with hot spots. In these cases we use antibacterial creme in addition to antibiotics that are given orally.

Prognosis

Allergic Dermatitis is a chronic disease that is not cured, only controlled. It can be the cause of significant frustration, and will wax and wane in some cases. Understanding this disease will help you formulate a long term plan that suits your needs and minimize the chance of side effects when medications are used on a long term basis.

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Worms (Internal Parasites)

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The study of parasites is called parasitology. It is an important discipline because internal parasites cause death and disease worth billions of dollars in animals each year. These parasites have highly evolved life cycles that make their elimination impossible. In addition, many internal parasites affect people with the potential for serious consequences.

Dogs and cats (especially puppies and kittens) are routinely infected with internal parasites, sometimes without apparent evidence of the infestation until it is too late. This means that a pet can have internal parasites even though the fecal sample is negative. It is suspected that internal parasites predispose your pet to IBD (Inflammatory Bowel Disease) later in life.

Fortunately, we have effective medications to treat most parasites. Many of the medications we use to treat internal parasites, called anthelmintics, treat more than one parasite. The advent of these broad spectrum anthelminitcs makes treatment much more effective. We recommend all dogs and cats get a treatment for internal parasites every 6 months.

This best method for treatment is to use flea products on a monthly basis that also kill internal parasites and prevent heart worms. We have several medications, some oral and some topical, to achieve this.

This section will discuss internal parasites that are commonly found in dogs and cats in our area. This includes:

  • Tapeworms
  • Roundworms
  • Hookworms
  • Whipworms
  • Coccidia
  • Giardia

These internal parasites differ from external parasites, which usually affect the skin and ears of dogs and cats. Click here to learn more about external parasites.


Symptoms

Symptoms manifested by pets that are infected with internal parasites can vary, and depend on a pet’s age, nutritional status, parasite load, duration of infestation, etc. One of the most common symptoms of internal parasitism is diarrhea. Other symptoms include poor appetite, lethargy, coughing, and abdominal distention. Some pets don’t show any symptoms while others can die from their infestation. Internal parasites tend to infest older and younger animals most commonly. Internal parasites can also make a pet more susceptible to other diseases. It is not uncommon for a puppy with Parvo virus to have internal parasites simultaneously.

Due to the prevalence of internal parasites in dogs and cats, their lack of symptoms in some cases, and the potential for humans to become infested also, your pets feces should be checked for internal parasites twice a year. Dogs and cats that are outside and exposed to other animals should have their feces checked more often. Routine worming should be performed on all dogs and cats every 6 months, even if the stool check for parasites is negative.


Diagnosis

The majority of internal parasites are diagnosed by microscopic examination of the feces for eggs that are released by the adult female in your pet’s intestine. The number of eggs released in a given fecal sample can be variable, sometimes there aren’t any even though your pet has an adult female parasite in its intestines. This means that a negative fecal report does not guarantee that your pet is free from internal parasites. In many cases we need to run numerous samples to feel comfortable that your pet is free of internal parasites. In some cases our doctor’s will treat for a specific parasite, even on a negative fecal sample, when they feel there is a likelihood of infestation, because some internal parasites eggs are notoriously hard to detect.

In some parasites a diagnosis is made by observation of the mature parasite in your pet’s feces or during an autopsy in your pet’s intestines. This is especially true for Tapeworms. Tapeworm eggs are difficult to detect during microscopic fecal analysis, so observation of the actual worm is how they are routinely diagnosed.

The two primary methods of fecal analysis are direct observation and fecal flotation. In direct observation a smear is made of some fecal material on a microscope slide and the slide is analyzed by one of our nurses for parasite eggs. It is used to detect eggs that don’t show up well during the fecal flotation.

Fecal flotation is the most accurate way to detect most internal parasites. A sample of fresh feces is put into a special solution that causes any eggs that might be present to float to the top and adhere to a cover slip. The cover slip is put on a microscope slide for analysis. This concentration of eggs substantially increases the chance of finding any eggs that might be present. Some eggs, notably Tapeworm eggs, dissolve during this process and might be undetected. This is the reason you can see Tapeworms in your pets stool yet the fecal analysis came back negative.

We have sanitary containers for you to use to obtain a fecal sample from your pet. Once the sample is obtained it should be kept cool until we analyze it. Analysis should be within 12 hours to increase accuracy.

The flotation solution has been added to the fecal container and a cover slip has been placed on the top to collect any eggs that float to the surface after a 5 minute wait

The cover slip is put on a microscope slide and carefully scanned for the eggs of any parasite. High magnification is needed because the eggs are microscopic in size.


Treatment

Internal parasites have very sophisticated life cycles that can make treatment difficult. Some of these life cycles involve mandatory maturation processes in other animals, including insects. Specific treatment modalities are set up to address these life cycles and will be discussed for each individual parasite in the following sections. It is important to follow these treatment regimens precisely.

Some parasites can only be controlled, not eliminated. In these cases it is important to check your pet’s feces routinely and to use medication on a long term basis.

There are new treatments for internal parasites that are very broad spectrum. They kill a wide variety of parasites, and are the medications we use as a routine wormer.

Revolution, will kill fleas, heartwormsear mites, and even internal parasites. We recommend it for cats.

Trifexis kills internal parasites, heartworms, and fleas, and is recommended for dogs.

Please ask our receptionist for brochures on these products.


Tapeworms

By far the most common internal parasite we encounter is Tapeworms. The scientific name for the Tapeworm we encounter in our area is called Dipylidium.

Life cycle

The source of the infestation is a flea that has been swallowed by your pet or a cat that eats infected rodents. The flea gets the Tapeworm in its system by swallowing it during its larval stages, when the larvae eat the eggs that have been passed from pets that are already infested with Tapeworms.

The lifecycle of the Tapeworm is simple compared to other internal parasites

Symptoms

In spite of their prevalence Tapeworms are not a significant cause of disease in dogs and cats. Most pets do not have any symptoms, and if symptoms are present, are mild in nature. Some pets will itch at their anus or scoot on the ground when the worms cause irritation as they pass.

Diagnosis

Most Tapeworms are diagnosed by visualizing the worm in your pets feces, crawling around its anus, or in its bedding. Tapeworms segments crawling on your dog’s anus might cause scooting, although full anal sacs are a much more common cause of scooting. They come in long attachments that usually break off into individual pieces when they exit from your pet. They usually look like pieces of white rice and turn yellow after they have been out of the body for a while.

This is a packet of Tapeworm eggs as viewed under a microscope. It is rare for us to see them in this packet because the fecal flotation solution causes this packet to burst.

 Treatment

Several medications are available that are highly effective at ridding you pet of Tapeworms. The most common treatment is an oral medication that rids your pet of all Tapeworms within 24 hours. This medication also kills rounds, hooks, and whipworms. It does nothing to prevent your pet from re-infecting itself. Proper flea control does.

Prevention

Since fleas are directly responsible for this infestation their control is apparent. We recommend advantage and Program for safe, economical, convenient, and highly effective flea prevention. A new product, called Revolution, will kill fleas, heartworms, ear mites, and even internal parasites. Please ask our receptionist for a brochure.

Public Health Significance

Children can pick up Tapeworms from eating fleas, but it rarely causes any problem. Other species of Tapeworms exist that have significant potential to cause serious disease in people. Fortunately, we do not encounter them in our local area in dogs and cats.

 Roundworms

A common parasite of dogs and cats, especially puppies and kittens, is Roundworms. The scientific name for their group is called ascarids. We routinely treat puppies and kittens for this parasite for 2 reasons. The first is their prevalence, the second is their potential to infest humans. The larval form of this parasite has the potential to cause serious disease in children. Fortunately it is a rare problem, and can be prevented by worming all puppies and kittens early in life. It is all prevented by monthly use of flea and heart worm prevention products like Trifexis for dogs and Revolution for cats, since these products also kill roundworms.

Life cycle

The life cycle of this parasite almost ensures that a puppy or a kitten will be exposed. They can get it from their mother while they are in the uterus (dogs), during nursing, and through contamination with infected feces. Larval forms of this parasite migrate through internal organs, get coughed up and swallowed, and become mature parasites in the small intestines. Intermediate hosts like rodents can become infected by eating eggs, and can then infect a dog or cat when they are eaten. Some larvae migrate to the tissues of internal organs and remain dormant until pregnancy where they become active and infect the developing puppies in the uterus.

 Symptoms

Common symptoms are a distended abdomen and diarrhea. Some puppies and kittens will be vomiting, lethargic and not eating well, while others will not show any symptoms. On rare occasions the parasite load can be so heavy that the intestines become obstructed. Coughing, fever, nasal discharge and even pneumonia can occur in pups that have large numbers of larvae migrating through their respiratory tract.

Diagnosis

In some cases the Roundworm will be present in your pet’s feces, vomitus or crawling around its ansu. This is not a consistent finding, and worms that might be present one day might not be there the next.

It looks like a curled up piece of spaghetti

The vast majority of Roundworm infestations are diagnosed on fecal analysis for eggs. Young puppies can be infected before the eggs of the parasite appear in the feces.

This is one type of Roundworm egg when viewed under the microscope. The thick membrane around the eggs prevent them from drying out when they are laid in the environment.

 Treatment

There are several effective treatments for Roundworms. We can easily treat your pet with an oral version given during a routine office visit. It has to be retreated in 2 weeks due to the migrating larvae since the medication does not kill the larvae. Some pets require several more treatments for a full cure. If you keep your pet on Trifexis or Revolution year round you are treating for this problem monthly. This is the best way to go.

Prevention

Roundworm eggs can remain viable for a long time in the environment. Children will get this parasite by eating dirt contaminated with the eggs, therefore cleaning up your pet’s feces immediately, and eliminating exposure to the feces of other animals when your pet goes for a walk, are important treatment modalities. Litter pans should be changed frequently and washed thoroughly and then allowed to dry in the sun. Keeping cats indoors also eliminates exposure to the feces of infected pets and the eating of infected rodents.

Public Health Significance

Children are of particular vulnerability to infestation because of their propensity to put things in their mouths and their attractions towards puppies. areas that might be contaminated with dog or cat feces should be off limits to children. This might include public areas such as parks or playgrounds. Even though these infestations in children are relatively uncommon, if they occur there can be significant damage to the internal organs like the liver, heart, brain, lungs, and eyes. This reason alone is why all puppies and kittens should be routinely treated for Roundworms, whether or not their fecal exam indicates they have parasites. also, teach your children to wash their hands frequently after handling pets, and not to put anything unnecessary in thier mouths.

Hookworms

Hookworms are blood sucking parasites that live in the small intestine. The scientific name for the Hookworm we encounter in our area is called Ancylostoma. They can be very pathogenic and even cause death due to anemia and low protein level.

Life cycle

Hookworms are spread by eating infected larvae that are in the environment. These infective larvae can also penetrate the skin and enter the blood stream where they mature into adult Hookworms in the small intestine. Puppies can also get infected while nursing or in the uterus prior to birth. Some Hookworm larvae migrate to muscles where they serve as a source of future infections.

 Symptoms

Pets with Hookworms have the potential to be very ill,especially in dogs. Symptoms include lethargy, dark stools or diarrhea, weakness and vomiting. In severe cases they are anemic and debilitated, especially the older and younger pets. The larvae might even irritate the skin when they penetrate between the toes and pads.

Diagnosis

Adult Hookworms are small so they are usually not seen passed in the feces. This diagnosis is made primarily by finding the distinctive egg in your pet’s feces. Any pet that is anemic should have its feces checked for this parasite.

These eggs are more oval than Roundworms, and the membrane is thinner

 Treatment

Infected pets might require hospitalization and even a blood transfusion if their symptoms are severe. There are different types of worming medications used, some require retreatment several weeks after the initial treatment because of the larvae that migrate through the body. All require checking your pet’s feces to make sure the parasite has been eliminated. Long term treatment and surveillance in the form of fecal exams are necessary. Dogs with chronic problems are put on heartworm preventive medication on a monthly basis since this medication also kills Hookworms. Any dog put on heartworm preventive medication needs to be checked for heartworm disease before we start preventive medication.

If you keep your pet on Trifexis or Revolution year round you are treating for this problem monthly. This is the best way to go.

Prevention

Fecal exams should be performed frequently on pets that have a history of Hookworm infestation. Prompt removal of feces helps prevent contamination of the yard with larvae. Larvae are killed in cold climates when exposed to freezing temperatures.

Public Health Significance

Hookworm larvae can penetrate the skin of people and cause significant irritation. These larvae can migrate through the body and cause damage to internal organs. Just like in Roundworms discussed above, puppies should be routinely treated for this parasite at a young age.

Whipworms

Whipworms are blood sucking parasites that live in the large intestine, usually only in dogs. They are called Whipworms because they have a slender end and a thick end, hence the appearance of a whip. The scientific name for the Whipworm we encounter in our area is called Trichuris. They can be as pathogenic as Hookworms, and also cause death due to anemia and low protein level.

Life cycle

Female Whipworms lay eggs in the environment that eventually turn into larvae. Pets ingest these larvae when they ingest soil that is contaminated. These larvae take 3 months to develop into adults capable of causing disease.

 Symptoms

Symptoms of Whipworm infestation include chronic diarrhea, anemia, and weight loss.

Diagnosis

Like most internal parasites Whipworms are diagnosed by looking for the eggs in the feces. They are oval in shape and have a plug at each end that aids in identification. Their thick membrane gives them significant protection. The eggs are shed intermittently, so a negative fecal sample does not guarantee that your dog is free of Whipworms. Adult Whipworms can sometimes be visualized when an endoscope is passed into the rectum of a pet with chronic diarrhea.

 


Treatment

Various oral medication are also used to treat Whipworms. Treatment is commonly repeated in 3 weeks and 3 months due to the life cycle of this parasite. If you keep your pet on Trifexis or Revolution year round you are treating for this problem monthly. This is the best way to go.

Prevention

Control of reinfections is difficult because eggs that have been laid in the environment are very resistant. Feces need to be rechecked and a long term plan for surveillance and treatment needs to be initiated.

Public Health Significance

Human infections with this parasite might occur, although this controversial. Common sense dictates prompt removal of feces from your pet’s environment and washing your hands any time there is a potential exposure.

Coccidia

Coccidia are not technically a worm, but a protozoan parasite that infect dogs and cats primarily, but can be seen in other species.

Life cycle

Coccidia life cycles are complex and involve many stages of development. Coccidia produce cysts instead of larvae and eggs. Dogs and cats usually get the infection from ingesting the cysts in the environment or eating animals like mice that are already infected.

Symptoms

Symptoms usually occur in young animals and include diarrhea and abdominal pain. These young animals can become severely dehydrated and the infection can be life threatening. This is especially true in pets that are stressed or have other parasites. Many pets, especially the older ones, do not show any symptoms when infected.

Diagnosis

Diagnosis of Coccidia infection is made by identifying the very small eggs in a fecal sample. They can be very difficult to detect due to their small nature and variable shedding by a pet. This is why our doctors will occasionally treat a pet for Coccidia even though the fecal exam is negative for this parasite.

 Treatment

Sulfa type medications or sulfa and antibiotic combinations are used to affect a cure. They need to be given for up to 3 weeks.  There is also a medication that requires only 3 days of treatment. Kittens that are very ill require hospitalization and intravenous fluids to help them fight off the infection.

Prevention

Prompt removal of feces helps prevent continued environmental contamination.

Public Health Significance

A version of Coccidia, called Toxoplasmosis, is of particular significance to pregnant women since it can cause disease in unborn children. The most common source of infection for pregnant women is eating improperly cooked meat (especially pork, lamb, and venison), not necessarily from the feces of cats. In a cat that does have Toxoplasmosis, the eggs that are laid in the environment (litter pan) do not become infective until 24 hours have passed. If the litter pan is cleaned twice daily the eggs will not have time to become infective to pregnant women. Wear gloves when you change the litter pan. Better yet,have someone else clean the litter pan. When you garden you should also wear gloves since stray cats may use the soil as a litter pan. Keeping your cat indoors and not feeding it raw meat will prevent it from getting Toxoplasmosis and passing it on.

According to the Centers for Disease Control and Prevention more than 60 million people in the United States are infected with the Toxoplasmosis parasite. Few have symptoms because a healthy immune systems keeps it in check. You may feel like you have the “flu,” swollen lymph glands, or muscle aches and pains that last for a few days to several weeks. However, most people who become infected with toxoplasmosis don’t know it. On the other hand, people with immune system problems, such as those with HIV/AIDS, those taking certain types of chemotherapy, or persons who have recently received an organ transplant, and infants, may develop severe toxoplasmosis, which results in damage to the eye or the brain. Infants who became infected before birth can be born retarded or with several other serious mental or physical problems.

Giardia

Giardia are also protozoal parasites that live in the small intestines. Giarida are found every where in the world, Infection rates are variable, with younger animals having a higher rate of infection. There are various strains that differ in their potential to cause disease. The strain called Giarda lamblis (also called intestinalis or duodenalis) is the primary strain of people, companion animals. and livestock.

This parasite can be found on fecal exams of healthy pets that don’t have any symptoms. It is probably under diagnosed due to the chronic nature of the problem it presents and the difficulty of coming up with a positive diagnosis.

Giardia exists in 2 forms; trophozoites and cysts. The active and motile form, called trophozoites, are the stage which lives in the intestines of an affected mammal. These trophozoites produce non-motile cysts which are shed into the environment. The cysts remain viable in the environment for months, especially in cool and moist areas. They thrive in clear and cool water, a good reason not to drink running water in the outdoors, no matter how pristine it looks. The cysts are killed by freezing, boiling, and extended contact with disinfectants.

It is theorized that giardia make pets prone to food allergies. By interfering with the intestinal lining they let in proteins that stimulate the immune system to cause an allergic reaction.

Life cycle

The cysts in a contaminated environment are transmitted to mammals or birds upon ingestion. Gastric acid and pancreatic enzymes work on these cysts in the stomach and intestines, causing them to release 2 trophozoites. These motile trophozoites attach to the lining of the small intestine where they interfere with digestion. Within 2 weeks they encyst and are passed in the feces to contaminate the environment and await another host.

 Symptoms

In many pets there aren’t any symptoms, while in others that do show symptoms, the problem might resolve by itself. The most susceptible pets are puppies and kittens, pets with other internal parasites, and debilitated pets. Diarrhea that occurs can be severe and can be accompanied by poor appetite and dehydration. Vomiting, weight loss and blood in the stool are occasional symptoms.

Diagnosis

Giardia can be hard to diagnose because the parasite cysts become shriveled in the routine fecal solution that is used to bring eggs to the surface and adhere to the cover slip. Special fecal flotation solutions (zinc sulfate) are a more accurate manner to make the diagnosis. Cysts can be shed intermittently, so several samples are sometimes needed to make this diagnosis.

Fresh fecal samples that are not put in the fecal solution can sometimes show the parasite. We sometimes send fecal solutions to our outside lab for special tests when we suspect the problem yet we don’t find the parasite. Just like Coccidia, our doctors might treat for this disease even on negative fecal samples.

 Treatment

Flagyl is the drug routinely used to treat Giardia, although it does not cure all Giardia infections. The usual course of therapy is for 5 days, although our doctors will vary this dose depending on specific circumstances. Other medications are sometimes used if the Flagyl is not effective. There is no drug that is 100% effective against Giardia.

We recommend treating pets that are positive for Giardia even if they don’t have any symptoms. This helps eliminate environmental contamination, and helps minimize spread to people. If one pet in a household has Giardia we recommend treating all pets.

Prevention

Giardia cysts in a kennel are relatively easy to destroy with routine disinfectants, and are susceptible to drying and heat. Once an environment like a lawn is contaminated though, it can be almost impossible to eliminate this parasite.

  1. Treat all in contact animals in the household.
  2. Recommend to bathe all pets every 7-14 days with mild hypoallergenic  shampoo like Hilyte or and oatmeal shampoo.  If unable to bathe then to wipe down with separate clean damp cloths/towels once a day or once every other day especially around the anal area (please save this area for last).
  3. Wipe feet and anal area  of affected pet at least once a day especially after going outside with a clean damp cloth/towel.  OK to use baby wipes around anal area.
  4. Prevent licking on surfaces outside, prevent from eating grass, and prevent from drinking water from communal water dishes at dog parks or from ponds or ditches as much as possible.
  5. Give bottle water or filtered water or water that has been boiled.  This filters should filter out up to Giardia and Cryptococcus organisms from tap water.  Boiling the water  will kill any organisms present in the tap water.
  6. Thoroughly clean food and water dishes daily with soap and hot water and sterilize the food and water dishes weekly.
  7. Pick up feces immediately or as soon as possible.  Recommend to thoroughly clean out litter boxes daily and to disinfect and sterilize the boxes at least once a week.
  8. Once done with medications bathe all pets or at least bathe both dogs and wipe down all feline pets in the house with separate clean damp cloths/towels. Also clean and vacuum entire house and clean all bedding.
  9. Once done with course of medications please bring a fecal sample the same day or the next day that the medications are finished.  If the fecal results are negative then do another fecal analysis in 30 days post-treatment.  If the fecal results are still  positive for Giardia then will recommend to proceed with other possible causes of this persistently high infestation with Giardia i.e. immune system problems that are preventing her from getting rid of this protozoal parasite.

Good nutrition, avoiding overcrowding, general parasite control, and proper sanitation procedures are all critical in prevention. Cleaning up feces on a daily basis goes a long way to preventing contamination.

A vaccine available for dogs is very helpful in persistent infections

Public Health Significance

According to the Centers for Disease Control and Prevention, Giardia is one of the most common causes of waterborne diseases in humans in the United States. Many people get Giardia from other people and and contaminated water. Symptoms in people include diarrhea, abdominal cramps and nausea. They appear within 2 weeks of exposure to the parasite.

Exposure comes from many sources. They include swallowing water from swimming pools, lakes, rivers or streams that have been contaminated with animal or human feces. Fruits and vegetables that have not been washed (with Giardia free water!), along with accidental ingestion from hands contaminated by using toys, bathrooms, changing tables, etc., are also sources of infection. This emphasizes the importance of routine washing of hands. Boiling drinking water for one minute will kill this parasite.

We routinely treat pets with Giardia in their feces, even if they are not showing any symptoms, because of the potential for people to pick up this disease. Washing your hands frequently after touching your pet and bathing your pet frequently will help minimize exposure. We have a vaccine for dogs that do not respond to routine treatment. This will help prevent human exposure.

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