Allergies (Canine)
Asthma (Feline)
Dog Flu

Allergies in dogs are a very common and often frustrating problem for pet owners.  As we head into the peak allergy months, many dogs will develop new or have flare-ups of old allergy problems.

To what can dogs become allergic?
The agents most frequently responsible for causing allergies are inhaled foreign material (allergens), including pollens from grasses, trees, weeds, house dust, and molds in the air.  Dogs can also become allergic to foods, external and internal parasites, drugs, hormones, and the bacteria present on their skin.  When an animal is exposed to an allergen that he is allergic to, his body reacts in an abnormal manner and produces clinical symptoms.

What are the clinical symptoms of inhalant allergies (atopy) in dogs?
The dog may chew or lick at his feet, rub his face or scratch almost any other part of the body.  The skin is often inflamed and has a bad odor.  Allergies typically begin between the ages of 1 and 3 years, but can occur as early as 4 months or as late as 10 years.  Less frequently, dogs may have respiratory problems associated with allergies as many people do.

How are allergies diagnosed?
Your veterinarian can often make a tentative diagnosis of allergies based on the history and clinical signs.  However, it is frequently necessary to evaluate skin scrapings, skin biopsies, cultures, food elimination trials, or blood tests to rule out other problems that may have similar clinical signs.

Skin testing
Specific identification of the allergy can be achieved by intradermal skin testing:  individual extracts of common allergens are injected into the skin.  If the patient is allergic to a specific agent, it will have a mild reaction at the injection site.  In about 70% of the dogs with inhalant allergies, intradermal skin testing can identify the allergy.

Eliza testing
This is a simple blood test.  Until recently, it has not been sufficiently sensitive in diagnosing specific allergies.  However, recent advances show promise, and in the future, this may be a useful alternative to skin testing.

How can allergies be treated?
It is important to realize that allergic disease in dogs can seldom be cured;  however, in most cases, it can be controlled.  If your pet is diagnosed as being allergic, there are 3 methods of treatment:

As you can see, there are several procedures necessary to evaluate, diagnose, and treat a dog with allergies.  You should consult with one of our veterinarians to determine which procedures are best for your dog.

Obstructive and allergic lung diseases affect many cats and are sometimes called “asthma,” “bronchitis,” or “bronchial asthma.”  Unfortunately, these diseases are not easily classified and probably represent a variety of lung disorders. They do share a common finding of “hyper-responsive” or “over-reactive” airways.

When the airway of a cat is sensitive to certain stimuli, exposure to these agents leads to narrowing of the airways. The inciting agents are usually direct irritants to the airways or things that provoke an allergic response in the respiratory tract. Regardless of the cause, the end-result is the same: muscle spasms in the bronchi (breathing tubes), buildup of mucus, and accumulation of cellular material. In particular, the inability to clear the bronchi of this material leaves the cat susceptible to secondary infections.

The cat is most stressed during expiration (forcing air out of the lungs). Difficult expiration or “breathing out” is typical with obstructive lung disease. Air may become effectively trapped in the lungs, causing them to over inflate. In some cases, this trapping leads to development of emphysema in the cat.

Are some cats more likely to get asthma?

Obstructive lung disease is most common in cats from two to eight years of age. Siamese cats seem to be at higher risk for developing asthma and bronchitis. Also, some reports indicate that it is more common in female cats.

What are the clinical signs?

Coughing and respiratory distress are the most commonly reported signs with obstructive lung disease. Coughing is a significant finding since there are relatively few causes of coughing in the cat. Also, many cats assume a squatting position with the neck extending during these coughing episodes. Wheezing is easily heard with the stethoscope and is sometimes so loud that it can be heard by the owners. Occasionally, sneezing and vomiting are noted.

What causes asthma?

As mentioned above, this group of diseases is characterized by hyper-responsive airways. The small breathing tubes (bronchi and bronchioles) can react to a number of stimuli, such as:

1.      Inhaled debris or irritants - dust from cat litter, cigarette smoke, perfume or hairspray, carpet fresheners, and perfumes in laundry detergent

How is asthma diagnosed?

Several tests may be performed to diagnose allergic lung disease in the cat.

1.      The minimum diagnostic tests include a complete blood count (CBC), blood chemistries, fecal exam and urinalysis.These tests will assess the general health of the cat and may provide clues as to the underlying cause. One particular type of white blood cell, the eosinophil, is commonly associated with allergic events and may provide support for a tentative diagnosis of asthma. Also, in some cats, special tests will be performed on stool samples for evidence of lungworms.

2.      Heartworm test. This is not indicated for all cats, as heartworms are less likely in some parts of the country. In areas where they are common, however, even cats that stay completely indoors are still at risk. Heartworm tests for cats are an area of intense research interest and their reliability is improving greatly.

3.      Feline leukemia and feline immunodeficiency virus tests. These tests are helpful in determining the overall health of the cat.

4.      Thoracic radiography (chest X-ray). Characteristic changes in the lungs are common on x-rays. Also, x-rays can be suggestive of heartworms or other types of heart and lung disease.

5.      Bronchoscopy, cytology and airway lavage (washing). Bronchoscopy is a procedure that allows the veterinarian to look down the airways of the anesthetized cat with a fiberoptic scope. After a visual examination of the airway is completed, the lining mucus of the bronchi may be sampled with a small brush. The mucus can be examined under a microscope (cytology). Finally, a small amount of sterile saline can be flushed into the airways to retrieve samples of material from deep in the lung. This material can be cultured for micro-organisms and can also be carefully studied under the microscope. The sediment can be evaluated for evidence of lungworms.

In some cases, an underlying cause cannot be identified, despite a thorough diagnostic workup. Even when the underlying cause is not identified, many cats can achieve a reasonable quality of life with medical management.

Some owners decline the complete workup for a variety of reasons. In such cases, it may be acceptable to treat the cat with a course of corticosteroids (“cortisone” or “steroids”) since most asthmatic cats respond favorably to these medications with few side-effects. However, this approach may create two problems. Corticosteroids can worsen secondary bacterial infections; therefore, prophylactic antibiotics are reasonable in cases where a workup cannot be performed. Cats with heartworms often cough like cats with asthma and will respond temporarily to corticosteroids. Therefore, cats in locations where heartworms are common in dogs may be misdiagnosed as having asthma.

How is asthma treated?

Successful management of allergic lung disease employs several therapies.

1.      Any factors known to trigger or aggravate breathing problems should be avoided. In some cases, this may mean trying different brands of cat litter, eliminating cigarette smoke from the home, etc. The previous list (see “Causes”) details some factors that should be considered. It is important to pay close attention to environmental factors that may aggravate the condition.

2.      Bronchodilators. These drugs are used to open up the airway and allow the cat to move air more freely. They should be used faithfully and as directed to obtain maximum effect.

3.      Corticosteroids. Steroids have a beneficial effect on decreasing inflammation, dilating the airway, and decreasing mucus production. In many cats, they are given daily. When the cat’s temperament is a concern, long-acting injections can be given as an alternative to pills. These drugs have potential for some side-effects and should not be withdrawn abruptly.

4.      Emergency treatment may employ bronchodilators, oxygen, rapid-acting glucocorticoids, and epinephrine. If your cat has heart disease, the attending veterinarian should be advised since epinephrine is best avoided.

Will my cat recover?

Cats with obstructive lung disease are usually manageable. Sometimes “cure” may be achieved if a specific underlying cause can be identified and treated.

Extreme respiratory distress constitutes an emergency and the cat should receive immediate attention.

The Dog flu has been in the news lately.  It has made it here to Colorado.  16 out of 53 samples sent to Cornell University have tested positive.  Although we should not panic, we should be aware of the signs.  Here is some information about this disease. 

What is Dog Flu?

Dog flu is an influenza virus that mutated from a horse influenza virus.

When was it discovered?

It was discovered at the end of 2003 in greyhounds on racetracks, mainly in Florida and New York.

What are the signs of the disease?

Dogs present with signs similar to kennel cough (but usually the cough sounds "wetter"), they sometimes have high fevers, and some have colored discharge out the nose.  Twenty percent of dogs with dog flu show no signs, but are "silent carriers."  These dogs do not appear sick, but spread the virus to other dogs.

Is there a vaccine?

No, there is no vaccine and there won't be one for at least a few years.

How many dogs die?

About 5-8% of dogs die of pneumonia.

Can people or cats get dog flu?

There has been no indication that people or cats can get dog flu.

Has it been found in Colorado?

Yes, 16 out of 53 samples sent to Cornell University have tested positive for this virus. 

What makes it so dangerous?

This is a very contagious disease.  You CAN bring this disease home to your dogs on your feet or on your clothes.  We recommend that you are very careful where you bring your dog.  If you notice a dog coughing, leave that place.  Because dogs do not have natural antibodies to it, most dogs that are exposed will get it. If you hear your own dog coughing, it's a good idea to have one of our vets check him/her out.  If caught early, your dog has a greater chance of getting over the virus. 

How can I find out more?

For more information, please visit these links:

Control of Canine Influenza in Dogs-Questions, Answers, and Interim Guidelines (AVMA)
Canine Influenza Backgrounder (AVMA)
Canine Influenza Virus Surfaces (JAVMA)