LBAH Informational Articles

Lick Granuloma

A very frustrating skin disease found mostly in dogs is called acral lick dermatitis (ALD), commonly know as a lick granuloma. Dogs with this disease lick incessantly, causing chronic skin lesions of the limbs.

Many aspects of ALD are similar to allergic dermatitis in general. This page will give you an opportunity to link to the aspects of the allergic dermatitis page that also apply to ALD.

Pathophysiology

Constant licking leads to hair loss and irritation of the skin. As the problem progresses the skin becomes ulcerated and infected. As the ulceration progresses nerves become inflamed and the area becomes pruritic (itchy), so much so that the dog can not stop licking. A vicious cycle develops and the condition becomes chronic.

It is theorized that some dogs get into such a licking habit, and actually derive pleasure from it, that once the initiating cause is eliminated they still continue to lick.

Cause

This is a disease that has many factors involved with the cause. Some of these work in combination, adding to the complexity of the problem. In some breeds, notably Doberman Pinschers and Great Danes, the cause might not be found. The most common causes include:

Allergic Dermatitis

This is considered the primary cause of the problem. We have a detailed page on allergies to learn more about this complex problem. Food allergy is a component of this also.

Arthritis

Joints in the area of the lesion can be painful, causing excessive licking of the skin over the area. Since the licking does not cure the problem, it continues, eventually causing significant skin lesions.

Neuropathies

Inflammation of the nerves under the skin in the area of the lesion can cause significant discomfort, again leading to excess licking.

Neoplasia

Skin cancer can cause chronic lesions that are uncomfortable and lead to chronic licking.

Fungal Infections

Deep seated fungal infections, including blastomycoses and Ringworm can initiate the problem.

Ectoparasites

External parasites like scabies and demodex are also potential causes.

Psychogenic

This is a catch-all term for psychological causes that are thought to be involved. They include boredom and stress factors. Similarities have been made between this and obsessive-compulsive disorders in people. When you see a dog licking incessantly at his legs you can see why this comparison is made.

Symptoms

The most consistent symptom in pets with ALD is excessive licking of the extremities, especially the front and rear legs. Lameness could occur due to infected skin or even arthritis. If the skin infection is serious enough there might be a lack of appetite (anorexia) or lethargy.

Diagnosis

The correct diagnosis for ALD does not come easy, so a thorough approach is needed. In every disease we encounter we follow the tenet’s 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 pets as they age.

  1. Signalment

    Several breeds are prone to ALD:

  2. History

    ALD usually starts appearing when dogs reach at least 5 years of age, especially the above breeds. When it first appears it might coincide with allergy symptoms that are seasonal in nature.

  3. Physical Exam

    This is a picture of the classic finding in a dog with ALD.

    If the skin infection is severe enough there might be swelling (cellulitis) due to the infection. Also, the lymph node that drains the affected area might be enlarged and there might even be a fever.

  4. Diagnostic Tests

    Diagnostic tests are important since many skin conditions look the same, even though they have different causes and are treated differently. In some situations other skin diseases can occur simultaneously with ALD.

    • Skin Scraping

      It is important to do a skin scraping in many cases of ALD because the symptoms and lesions commonly mimic those of ectoparasites like demodexor scabies.

    • Fungal Culture

      Ringworm lesions can look similar to ALD lesions. In Ringworm there is usually not as much licking.

    • Radiography

      If we suspect the licking is from a painful joint we can sometimes make this diagnosis from an x-ray.

    • Skin Biopsy

      This test is used to help differentiate skin tumors or deep fungal infections as the initial cause of ALD.

    • Fine Needle aspiration

      As an alternative to an actual skin biopsy we can do a simpler test called a fine needle aspirate. In this test we use a syringe with a tiny needle to take a sample of the affected area. This sample is put on a microscope slide for analysis by one of our pathologists.

      It does not require general or local anesthesia and can be performed during an office call. Only a small amount of tissue is sent to the lab for analysis, so it is not always possible to make a complete diagnosis this way.

    • Bacterial Culture

      This test will give us an indication of the type of bacteria involved. Staphylococcus and Enterobacter are the more common pathogens. Since the top of the lesion is contaminated with many bacteria, some of which are not part of the problem, a culture is performed on biopsy samples that are taken in a sterile manner.

    • Allergy Test

      Allergies can be a major component of ALD. Please refer to our allergic dermatitis page due learn about allergy testing.

Treatment

ALD tends to be a chronic disease that leads to significant frustration. The wide variety of treatments that are used to treat ALD are an indication of the complexity of this disease and the fact that many different causes, some working in tandem, are involved.

Flea Control

We can not emphasize the importance of proper flea control in any pet that has a skin condition since we live in a flea endemic area year round. Even pets that are 100% indoors are possible flea victims.

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 two main products we recommend are Trifexis for dogs© and Revolution for cats©. We have detailed brochures on each to explain how they work, please ask one of our receptionists. In addition to treating fleas they prevent heartworms and treat parasites.

Anti-inflammatories

Cortisone is used initially to minimize swelling and licking. It is not used as the primary means to control ALD in the long term since a skin infection is almost always present and cortisone decreases the immune system’s ability to fight this infection. Cortisone is used much more often in treating allergic dermatitis. There is a section there on its proper use.

As an option to using cortisone to minimize the licking we suggest the use of elizabethan collars. A good option that is tolerated well by larger dogs is a small plastic bucket with a hole cut out of the bottom that is placed over the head.

Antibiotics

Oral antibiotics are the most important treatment we have for ALD. In some cases we need to use them for 4-6 months due to the chronic nature of the problem. It is important to continue them for at least 3 weeks after the skin looks healed. In some pets we put them on intermittent antibiotic therapy for the rest of their lives- this is called pulse therapy.

Antibiotics that work best include:

  • Cephalexin
  • Primor
  • Baytril
  • Clavamox

Laser Therapy

We have had success using our laser machine in the treatment of this problem. It usually takes at least 3 treatments, and in some cases can be a significant help in minimizing the licking.

This Labrador has an ALD lesion on top of its rear foot area. It is been prepped or laser treatment.

The laser is being used at a light setting with an intermittent pulse.

The appearance of the lesion immediately post laser treatment.

Pain Medication

Initially it is useful to put your pet on pain medication until the antibiotics and other treatments start working. NSAID’s like Rimadyl can because because they decrease inflammation and also pain. Tramadol can also be used initially.

Antifungals

If a deep seated fungal infection is diagnosed we will use oral fungal medication for an extended period.

Allergy Shots

This can be a good way to minimize itching without using cortisone. The less we use cortisone to minimize itching the faster the problem will resolve. These are injections give on a long term basis, usually once per month once the allergy is improving.

Food allergy

We recommend feeding hypoallergenic diets to any pet that has a skin condition caused by an allergy.

Food Supplements

Some allergic dogs and cats scratch less when supplemented with essential fatty acids. The main ones we use are Derm Caps and EFa-Z.

Surgery

This is not a rewarding way to treat ALD since the problem commonly recurs after the surgery.

Topical Medications

It is a natural tendency to want to use topical medication only on a skin problem. If used in combination with long term oral antibiotics this topical medication can be beneficial. They are not effective when used alone.

Behavioral Modification Medications

Some dogs are compulsive lickers without any obvious cause. Some veterinarians believe that the incessant licking in ALD is similar to the exaggerated grooming habits of people with obsessive-compulsive disorders.

These medications are helpful, but do have the potential to cause side effects, especially when used with other medications. One of our doctors will let you know if they apply in your situation.

Veterinary Neuronal Adjustment

An additional treatment modality used to treat ALD is VNA. It is a non-invasive and non-painful way to stimulate the nervous system to stop the sensation that is causing the problem.

Prognosis

ALD has a guarded prognosis. An early and accurate diagnosis (when one is apparent) offers the best option by instituting proper medication before the problem becomes so chronic that treatment is only marginally effective.

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Rabies

Rabies is a viral disease of warm blooded animals (you won’t see Rabies in birds and reptiles) that occurs world wide, with significant human health significance due to its fatal nature. Various outbreaks have occurred in the United States in the last decade. Adequate vaccination of dogs and cats is the primary line of defense in preventing outbreaks. The Centers for Disease Control and Prevention, along with the veterinary community, produce reports detailing the incidence of rabies in specific areas of the country. Thousands of animal rabies cases are reported every year, with the actual number of cases being much higher. The majority of rabies cases in animals in the U.S. occur along the East coast, with pockets of rabies in various other states.

Approximately 500 cases of human rabies are reported yearly, with the actual number again being probably much higher. Discrepancies in diagnosis and reporting make actual numbers hard to come by. Several countries are free of rabies, and institute extreme quarantine measures to prevent spread.

We have never seen a case of rabies in our hospital, a testimony to the effectiveness of the rabies vaccine.

Cause

Rabies is caused by an RNA virus belonging to the order Mononegavirales. All warm-blooded animals, including humans, are susceptible. Raccoons, skunks, bats and foxes, account for 90% of the cases in the U.S., with raccoons making up the majority, followed by skunks, bats, and foxes. Forty years ago it was the domestic animals that accounted for the majority of the cases. More cats get rabies than dogs.

Transmission

When a wild animal is bitten by a rabid animal the virus enters the bloodstream, eventually spreading to the spinal cord and brain. It remains there for up to 3 months, during which time the affected animal has no symptoms of rabies. When the virus passes to the salivary glands the animal shows symptoms, and will usually die within 7 days. It is during this time that it can infect another wild animal, a human, or a dog or cat.

The main animals that infect humans are dogs, cats, cattle and horses, because they are exposed to these animals much more than wildlife. In addition to bite wounds, the virus can rarely be transmitted through the mucous membranes, as an aerosol, and through cornea transplants.

Symptoms

Clinical signs of rabies are quite variable, with a change in behavior being one of them more consistent findings. This behavior change can be as subtle as apprehension, or as extreme as biting in a normally friendly dog. Dogs might chew at the site they were bitten when they became infected, and can even maim themselves.

As the disease progresses dogs may show increased irritability, viciousness, excitability, and eating unusual objects (pica) like wood. These dogs may hide in dark or quiet places, and will bite when provoked. Central nervous system signs like seizures will exhibit, and there may be paralysis prior to death.

A phase of the disease causes paralysis of the muscles in the throat. This leads to excessive drooling and choking sounds due to an inability to swallow, and is the sign most people think of when describing rabies. It is also common for people to think their dog has something stuck in its throat, and cause themselves to be exposed to virus laden saliva when attempting to removed the suspected foreign body.

Diagnosis

The disease is suspected in dogs that show neurological signs consistent with rabies, and may or may not have been bitten by another animal. Since these signs are so variable rabies needs to be considered in any dog showing behavioral changes. Blood samples are not helpful in the diagnosis. The only way to confirm a diagnosis of rabies in animals is to have the brain examined. A test called Fluorescent Antibody (FA) is performed on the brain cells of a dead animal.

In humans tests for the virus are performed on saliva, serum, spinal fluid and skin biopsies. In some cases the test checks for antibodies to the rabies virus, in other cases it looks for the virus itself.

Treatment

Animals that have rabies are not treated because they can shed the virus in their saliva for extended periods.

Prevention

The vaccination of dogs by a licensed veterinarian is the most effective means to control rabies. Every state has specific laws regarding vaccines. They are usually given to dogs at 4-6 months of age, repeated one year later, then every 3 years. In order to get a dog license, a certificate of vaccination by a veterinarian licensed in that state must be presented. Rabies vaccine is given to animals only under the supervision of a veterinarian licensed in that state. Cats are also given rabies vaccines.

In humans a pre-exposure vaccine is given to high risk groups, usually veterinarians, animal handlers, and laboratory workers. By giving this vaccine prior to any exposure to rabies, a person that eventually gets exposed to the rabies virus will need less post-exposure treatment, and will partially protect people that were exposed to rabies without realizing it. approximately 18,000 people per year received this pre-exposure vaccine, while 40,000 people per year receive the vaccine after they have been exposed.

Public Health Significance

Rabies has extreme human health significance due to the fatal nature of this disease. Symptoms include fever, headache, anxiety, confusion, hypersalivation, paralysis, and ultimately even death. In the early 1900’s more than 100 people died annually from rabies in the U.S. That number is down to 1-2 per year, because of vaccination of domestic animals and post exposure treatment. Most people in the U.S. die from rabies because they were not aware they were exposed to the virus, and never sought treatment. Post exposure treatment in humans has to be instituted before any symptoms appear for it to be effective in preventing death.

Most humans are infected by a dog bite, therefore aggressive wound cleansing can be of help. Tens of thousand of people are given rabies shots after being bitten, this therapy has proven to be highly effective. High risk groups (people that work extensively with sick animals like veterinary hospital personnel) can receive vaccines prior to exposure. animals that have bitten people must be quarantined for 5-10 days, depending on local laws, to observe for any signs of disease. Animals that have bitten someone are not euthanized unless they have successfully passed their quarantine period or their brain is scheduled for an examination.

The Centers for Disease Control and Prevention has an extensive section on rabies if you would like more information.

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Ringworm

An occasional cause of skin conditions in pets is caused by Ringworm. The scientific name for this disease is Dermatophytosis. It is caused by a fungus not a worm, and the lesion is not always in the shape of a ring. Since fungi are everywhere in our environment, it is difficult to determine which pets will develop the problem. The fungus that causes Ringworm can be cultured from the hair coats of normal dogs and cats. These pets might be carriers of the disease to other pets along with people. We tend to see the problem more in young animals.

People will sometimes pick up a case of Ringworm from their pet, but just because a pet has Ringworm does not necessarily mean that the people that interact with that pet will develop the problem. A dog or cat can transmit Ringworm to a person without showing any symptoms at all.

Cause

There are 3 specific fungi of significance in this disease.

  • Microsporum canis

The source of this species of Ringworm is almost always a cat.

  • Microsporum gypseum

This species of Ringworm is usually from dogs and cats that dig into contaminated soil.

  • Trichophyton mentagrophytes

This species infects dogs and cats when they are exposed to rodents or the burrows they live in.

In cats, almost all cases of Ringworm are caused by Microsporum canis. In dogs the majority of cases are caused by Microsporum canis. Which of these 3 main dermatophytes causes the Ringworm in dogs depends on geographic location.

Symptoms

The skin lesions that appear with Ringworm are variable, and do not necessarily form a ring. There will be hair loss, usually in small patches at first. as time goes on the patches may disappear or appear at other locations on the skin. There might be scratching due to itchiness. If the hair loss occurs on the face or feet there is a chance it is due to digging habits or exposure to rodents.

This patch is typical of the lesion seen in Ringworm. A diagnosis of this disease can not be made based just on the appearance of this lesion because other skin conditions (Demodex for example) can show similar lesions.

Diagnosis

There are several different ways to diagnose Ringworm. All require some type of test because it is impossible to make the diagnosis just by looking at the skin. This concept holds true for all skin conditions; making a diagnosis of a skin disease requires all of the aspects of the diagnostic process.

If a person in a household has been positively identified with Ringworm by their physician it is possible they obtained it from their pet, even if their pet has no symptoms of the disease. This is especially important in multiple cat households. We will culture these pets using the culture technique we describe below, but in this case, we might run a new toothbrush over the hair coat to obtain a sample for culture.

One of the simplest ways to diagnose Ringworm is with the Woods lamp, which is an ultraviolet lamp, also know as a black light. 50% of the Microsporum canis species will fluoresce when the Woods lamp is placed near the area of hair loss.

The lamp emits a purple/blue glow from the tube, and when there is fluorescence on the skin, it has a greenish appearance. Other material on the skin (dander, medication, etc.) can also fluoresce, so interpretation is important.

Since only 50% of a certain species of Ringworm fluoresces under the glow of the Woods lamp, a culture is used to verify the diagnosis:

The first step in the culture process is to gently remove hair follicles in the area of the lesion

These hairs are cultured in a special media that inhibits bacterial growth and enhances fungal growth. This culture can be sent to our outside lab or done in house. Since a fungus is a slow growing organism it can take up to several weeks to determine if there is growth or not.

The positive culture on the right, from our in house lab, demonstrates two findings that are needed for a positive diagnosis. The first is the cottonish fungal growth, and the second is the reddish color of the culture media. This color change must occur at the same time the fungal growth appears.

The culture media prior to the start of the test. Positive fungal growth after 10 days of incubation at room temperature.

Treatment

Topical shampoo therapy is used in almost every case, especially in longer haired pets. It is common to clip some or all of the hair in some pets to make it more effective. These baths will also remove infected hairs that can be the source of an infection to people or other animals.

Specific anti fungal cremes are also used when a pet is infected in an area that already has sparse hair growth, or there are small, discrete lesions.

Oral anti fungal medications are also used in select cases. They have the potential to cause side effects, so their use is confined to specific situations.

In some pets the disease may resolve by itself.

Prevention

Since fungi are everywhere it is almost impossible to prevent exposure. Pets that chase rodents, especially into burrows, might be at an increased risk.

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Allergic Dermatitis

Allergies are a common cause of skin conditions in dogs and cats. This type of allergy goes by several names: the most common are atopy, allergic skin disease, or allergic inhalant dermatitis.

The main difference between us and pets is that allergies in pets tend to cause skin conditions, as opposed to runny eyes, runny noses, and sneezing we encounter in people. Along with other skin conditions besides allergies,  symptoms typically include scratching and itching. Medically this 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 pets 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:

    1. 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.
    2. 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.
    3. 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 pets 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.
      • 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.

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
    1. 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

  1. History
    Atopy, in it’s initial stage, tends to be a season 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.
  2. 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. 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 removed.


    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.


  3. 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

      Collar- Canine

Serestro

      Topical- Feline

Advantage II

Revolution

Vectra

       Oral- Feline

Comfortis

       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.

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.

Apoquel

There is a relatively new medication available that shows great promise in treating atopy. It’s our fallback medication when the other treatments do not work. We give it for a 10 day trial the first time. Some dogs stop their itching and stay this way for quite a while. Other dogs need to be on Apoquel long term.

It 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.

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 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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Spay Canine

One of the most common surgical procedures we perform on dogs is a spay, known medically as an ovariohysterectomy (removal of the ovaries and uterus). It is performed for several medical reasons:

  • It prevents dogs from going into heat.
  • It prevents dogs from getting pregnant.
  • It significantly helps prevent dogs from get breast cancer later in life.
  • It prevents dogs from getting uterine infections later in life. An infected uterus is called a pyometra, and is a serious disease. After you view the pictures of a routine surgery you will be given an chance to see a picture of the uterus of a dog that has a pyometra.

In addition to these medical reasons, it prevents unwanted pregnancies, a significant problem in our society. Millions of dogs are euthanized every year because they are strays.

We usually spay a dog when it is around 6 months of age. This timetable is variable, the important point is to perform the surgery before it goes into heat. The ongoing old wives tale that states dogs should go into heat before spaying is incorrect. Most dogs go into heat twice each year.

On the day of surgery we need your pet in the hospital between 7:30 AM and 8 AM. Please take away all food and water when you go to bed the evening before surgery, and do not give your cat anything to eat or drink the morning of surgery.

Our surgeon will call you after the surgery is complete and your dog is awake. It can go home in the late afternoon the day of surgery. Please call our office at 4 PM for pickup time, you will be given written post operative instructions then. We are open in the evening if you need to pick up later.

This page contains graphic pictures of an actual surgical procedure performed at the hospital.


 

 

Anesthesia

 

Pre-anesthetic preparation is important in every surgery we perform, no matter how routine, because surgery is not an area to cut corners. All of our spays receive a physical exam prior to surgery. Only if they pass this exam will we draw a small amount of blood for an in-hospital pre-anesthetic test. When everything is to our satisfaction we will administer a sedative. This will calm the pet down and make the administration of the actual anesthetic, along with post operative recovery, much smoother. Once a pet is anesthetized, prepared for surgery, and had its monitoring equipment hooked up and reading accurately, the surgery can begin.

Once our surgeon has scrubbed up and is  in sterile gown, gloves, and mask, the surgery begins

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While our patient is being anesthetized our surgeon is already in our surgical suite setting up instruments. Our surgeon is ready to start before our patient is at a proper plane of anesthesia. Once the anesthetist gives the green light the surgery starts immediately. We want our surgeon waiting for his patient, not the other way around.  All of this is to minimize anesthetic time.

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We keep a close tab on important physiologic parameters for all of our surgeries. Monitors like this give us an early warning of an impending problem.

This machine monitors:

Temperature

Heart Rate

Heart rhythm

Oxygen saturation

Carbon dioxide level

Respiratory rate

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In addition to our monitoring equipment our anesthetist stays “hands on” in monitoring important physiologic parameters

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Surgery

 

Every major surgery we perform begins with proper patient preparation. This will help prevent infection, which could be a serious complication in this surgery because during a spay we have an opening into the abdomen.

Our nurse is using a special cleaning agent and scrubbing the skin 3x in a circular motion

This is the final look of the skin in a pet that is ready for surgery. In the very center of the screen is the umbilicus (belly button), an important landmark for the surgery.

The surgeon makes an incision near the umbilicus and extends it 3-5 inches in the direction of the tail (the tail is at the left in this picture). We try to make our incisions as small as possible to minimize anesthetic time, decrease post operative discomfort, and minimize the healing time.

 

The tissue just underneath the skin is called the subcutaneous layer. It consists mostly of fat and small blood vessels, and is the next layer we cut into after the skin. If these small blood vessels don’t clot within a few minutes they are clamped with instruments, and if necessary, they are cauterized.

 

The final layer we need to cut before we are actually into the abdomen is called the linea alba. It is an area of muscle in the center of the abdomen that is covered by a tough layer of tissue. This is the most important layer resutured at the end of the surgery because it is the only layer strong enough to hold the abdominal muscles together to prevent a hernia. In this picture the linea is being held up with a forceps and a scalpel blade (held upside down) is being used to make the incision.

 

A scissors is commonly used to extend the linea incision and facilitate the removal of the uterus. Care has to be taken not to puncture internal organs like the bladder.

 

Buried within the abdominal organs and abdominal fat is the uterus. A special instrument called a spay hook is sometimes utilized to gently pull one of the uterine horns through the abdominal incision. In this picture our surgeon is using his finger to bring the uterus out of the incision.

 

The uterine horn is traced into the body cavity until the ovary is found. It has to be gently teased from its location near the kidneys in order to be able to pull it out through the abdominal incision. In older dogs this part of the procedure is much more difficult. The ovary (arrow) is usually covered with fat.

 

The blood supply to the ovary is extensive so a special technique is utilized to prevent hemorrhage. This technique involves the use of 3 clamps. In this picture the first clamp is being applied to the left of the ovary (arrow). Besides making it easier to place a suture on the tissue, this clamp stops the flow of blood from within the abdomen to the ovary.

 

A second clamp is applied just above the first. The third and final clamp is applied to the right of the ovary (arrow). All of the tissue to the right of the second clamp is removed during the surgery.

 

The tissue is cut with a scissors between the second and third clamp

 

The third clamp (with ovary) is pulled away leaving the first two clamps to prevent any hemorrhage.

 

Two sutures are securely placed under the first two clamps. When the surgeon is certain there is no risk of bleeding the clamps are released and the sutured tissue is allowed to fall back into the abdomen. In this picture one of the two clamps has been removed and the second suture is being placed. This whole process is repeated for the other ovary that female dogs have in their abdomen.

 

Both ovaries with their attached clamps have been removed from the abdominal cavity. They have been pulled towards the right enabling the surgeon to gently pull the cervix out of the abdominal cavity also.

 

In this picture the two ovaries are off the screen to the far right. Two clamps are placed at the cervix and the remaining body of the uterus with its two attached ovaries is cut away.

 

The uterus is sutured in the same manner at the ovaries, with two secure stitches placed under the clamps. Once our surgeon is certain the cervix sutures are secure the cervix is placed back into the abdominal cavity.

 

The linea alba is now securely resutured. Stainless steel sutures are sometimes used because they are very strong, cause minimal tissue reaction, and show up vividly on an x-ray of the abdomen .

 

The subcutaneous layer is now closed with a type of suture that dissolves over several months.

 

The last layer sutured is the skin. Sometimes we put the sutures on the outside, which means they have to be removed in 7-10 days. In this example we put the sutures in just under the skin, so no removal is needed. They will dissolve on their own in a few months just like the sutures in the subcutaneous tissue.

 

It is at this point that we will give a pain injection, which might make this dog groggy for the evening. When you pick up a pet after a spay operation you will be given detailed post operative instructions.

 


Infected Uterus

 

This is a picture of a uterus in a female dog that has an infected uterus, called a pyometra. The uterus is completely filled with pus, and this dog is very ill. If surgery is not performed to remove this uterus it could rupture and even cause death. The uterine tissue is very fragile and can easily rupture during the surgery, so great care is taken to prevent any release of pus into the abdominal cavity.

 

An occasional pyometra can be tremendous in size. Great care has to be taken to minimize this uterus from rupturing during the surgery.

 

A diagnosis of pyometra is made based on several findings. There is a history of being in heat a few months prior, along with lethargy, lack of appetite, and sometimes even vomiting. Most dogs will be drinking and urinating excessively because of the toxic effects of the infection on the kidneys. A blood sample will somtimes show a very elevated white blood cell count, and an x-ray of the abdomen might show an enlarged uterus.

This x-ray shows an enlarged uterus in the abdomen. The uterus (U) is the area just to the left of the bladder (B). You can see it as several areas that are circular or elongate. A normal uterus does not usually show up on an x-ray.

 

Postoperative Care

 

Most dogs go home late in the afternoon on the day we perform the surgery. They might be groggy from the pain injection which is advantageous because they will remain calm and allow the healing process to start immediately. By the following morning the grogginess will have worn off.

When you first get home do not be in a big rush to feed. After 1 hour at home offer a small amount of food and water. If the appetite is good, offer more several hours later. Do not over do the feeding the first night because anesthesia can make them nauseous.

Keep contact with children and other pets to a minimum the first night, and restric activity for several days to allow the incision to heal. Do not let your dog go outside until healing is complete.

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Guinea Pig X-Rays

This little guy is laying on his back, with the front legs towards the top. The big dark spot the arrow is pointing to is air in the intestines, and is normal. Did you notice he is missing one of his front legs? It was amputated years earlier.


 

This is the same pig from the side view. Can you tell he has only one front leg from this view?

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Guinea Pig Eye Surgery

This cute little one had a problem with his eye. Here he is starting his anesthesia before surgery.

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All of our small patients are kept on a special warm water blanket to prevent hypothermia

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The problem is a congenital hair irritating the cornea

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Our patient is prepped and draped for surgery. You can see how this hair is attached under the eyelid.

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This is meticulous surgery so Dr. R needs magnification (he looks like an alien creature)!

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We use the laser for many reasons. It gently removes the hair, and it does this without any bleeding or inflammation. This is important in this very sensitive area. In the years before we had the laser we used a small scalpel blade. Even though it was a small blade it still caused bleeding and inflammation post operatively.

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No more hair, and more importantly to our surgeon, no bleeding or swelling

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Lisa keeps a close tab postoperatively to make sure our small patients wake up without any problems

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Rat Neuter

We use the laser on our all our neuters, including small animals like rats. As you will see from the following pictures there is no bleeding with the laser, which means less anesthesia time and less postoperative pain and swelling.

Click on any photo to enlarge it.

Graphic photos of an actual laser neuter are on this page.


 

Our patient has been prepped and is ready for surgery

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We start the procedure by gently stabilizing the testicle before we turn on the laser

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The initial cut is rapid. You can see fat over the testicle as our surgeon gently squeezes the testicle through the opening.

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When fully exteriorized you can see a layer of tissue and blood vessels over the testicle. This layer of tissue is called the tunica vaginalis.

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The laser cuts through the tunica vaginalis and the testicle is gently pulled out.

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The blood supply is now ligated with a special suture that will slowly dissolve over several months

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The laser is used to cut the testicle away from the rest of the body

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Tissue glue is applied instead of sutures to aid in healing and prevent chewing

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This little guy will go home (weighing a few grams less) and heal up in 1-2 days.  There is no need to return for suture removal because no sutures were placed in the scrotum.

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Mange (Guinea Pig)

Mange in Guinea Pigs is caused by a parasite that is similar to the scabies parasite in people. It is seen more often in households that have several pigs. This disease occurs in other animals also, including dogs and cats.


Cause

Mange is caused by a parasite know as Sarcoptes. It is transmitted by direct contact, usually when a new pig that has the mite is introduced with pets already in your household. The mites that cause mange in guinea pigs does not affect humans.

Symptoms

Most Guinea Pigs that have Mange are itching and have patches of hair loss. Some even lose weight and have unhealthy looking hair coats.

This little guy has the problem on his face and his arms

 

This pig has a patch of hair missing on his backside. He also has infected skin secondary to the scratching.

Diagnosis

Any pig that has hair loss and is scratching is a suspect for Mange. The primary method of diagnosis is with a skin scraping.

Treatment

The usual treatment for Mange is a drug called Ivermectin. Usually 2-3 injections are given between 1-2 weeks apart.

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Rat Ovarian Tumor

Rats are prone to tumors, commonly in the mammary glands and in the uterus. These tumors can be benign or malignant. Removing them as soon as they are noted makes for a much better prognosis. This page has a surgery on the removal of an ovarian tumor.

This area contains graphic pictures of an actual tumor removal performed at the hospital. 

Surgery

Our patient that has been prepared for surgery shows an obvious abdominal bulge. The head is towards the left, and it is laying on its back.

An incision is carefully made in the the skin.

The distention in the abdomen from the large tumor causes the muscle layer to bulge out further.

We have to carefully incise this muscle layer without touching the bulging abdominal contents.

A scissors is carefully used to enlarge the incision enabling us to remove the large tumor.

The first organ encountered is the enlarged cancerous ovary. All the nodules are cancerous tissue.

This is the small uterus with the very enlarged and cancerous ovary attached. The cancerous ovary is much larger than the whole uterus. The diagram below helps identify the organs

The blue lines outline the normal uterus, while the green lines circle the huge and cancerous ovary.

The uterus is clamped and the majority of it, including the cancerous ovary, is removed.

The cancerous ovary that has been removed is probably 10x its normal size.

The muscle layer is sewn back together with stainless steel wire, seen here being started on the left. It is very strong and causes minimal tissue reaction. It will stay here for the rest of this pet’s life.

The skin is also sutured with stainless steel. Rats are chewers, so stainless steel is used in the skin also because it is difficult to chew out. The sutures will be removed in 7-10 days.

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