Airborne particles (pollen, dander, etc.) are harmless to someone who is not allergic to them. Allergy develops in individuals who are genetically programmed to do so – This includes our dog and cat companions.
Features of Atopy (allergy to airborne things)
There are many reasons for pets to itch: parasites, allergy to flea bites, food allergy, secondary infection and the list goes on.
The following are findings in the history and examination of the patient that might lead to a diagnosis of atopy. In fact, meeting five criteria from this list yields an 85 percent accuracy for the diagnosis of atopic dermatitis, at least for dogs:
Young age of onset
Seasonal itchiness due to atopy tends to begin early in a pet’s life (between ages 1 and 3 years in 70 percent of dogs diagnosed with atopy). Food allergy tends to begin later (more like age 5 or 6 years in dogs) or earlier (less than 6 months of age). Age at which itching first manifests is not as reliable a sign in cats as in dogs.
Mostly indoor lifestyle
It is indoors where many airborne allergens concentrated; however, it is important to note that allergens in the air are in the air for miles so it is not easy to escape allergens by simply going outdoors nor by simply going indoors.
Good response to steroids
Whether the patient is a dog or cat, itchiness due to atopy responds rapidly to cortisone-type medications (prednisone, depomedrol, dexamethasone, etc.) as does itching due to insect bite allergy. Food allergy is more variable in its response; it may or may not respond well.
Chronic or recurring yeast infections in the skin
Yeast (Malassezia pachydermatis) live on the surface of the skin normally but with all the changes allergy causes to the skin’s microenvironment, yeast will proliferate and create a stinky, thickened, pigmented skin that resembles elephant skin or even tree bark. Environmental allergy is a strong predisposing factor in developing yeast dermatitis.
Front feet involved
Ear flaps involved
There is a lesion distribution that is common in inhalant allergy. It is, unfortunately, very similar to that of sarcoptic mange and overlaps greatly with the lesion distribution of flea bite allergy.
Ear margins not involved
Ear margin involvement is suggestive of sarcoptic mange and would lead one away from airborne allergies.
Lower back area not involved
The lower back is the flea bite zone. There are few conditions other than flea bite allergy that cause itching in this area, so if this area is involved, make sure flea control is achieved before further evaluating the skin.
Seasonality of the itching is also a clue towards an airborne-related allergy, but since there are many climates where seasons are ambiguous, this is not necessarily a hard and fast feature of atopic dermatitis.
If your animal companion suffers from itching and chewing on him or herself, call Urban Animal and schedule and allergy evaluation today!