Aloha! You're speaking with Dr. Michael Salkin
Punch biopsies of Poco's skin should be confirmative of either miliary dermatitis or eosinophilic dermatitis - both of which are considered to have an allergic basis. When lesions are present caudal (toward the tail) to the edge of the rib cage, a flea saliva allergy is most common. Our dermatologists tell us to apply an effective over the counter flea spot-on such as Advantage or a fipronil-containing product such as Frontline or one of the newer prescription products available from Poco's vet even if fleas aren't seen. Cats can be such effective groomers so as to eliminate all evidence of flea infestation. Indoor cats can contract fleas because we walk them in on us and flea eggs and larva can remain viable in your home for months. As the weather warms at this time of year, egg hatches are common. In severe cases, an anti-allergenic prescription corticosteroid such as prednisolone will work wonders for cats allergic to the saliva of the flea. Your other pets may not be allergic to the saliva of the flea.
Atopic dermatitis - allergies to environmental allergens such as pollens, molds, dust, and dust mites, etc. - should also be considered and is also quite responsive to prednisolone. A food
intolerance rounds out the common etiologies for these skin conditions but isn't expected to be responsive to prednisone.
Food intolerance/allergy is addressed with prescription hypoallergenic diets. These special foods contain just one novel (rabbit, duck, e.g.) animal protein or proteins that have been chemically altered (hydrolyzed) to the point that Poco's immune system doesn't "see" anything to be allergic to. The over the counter hypoallergenic foods too often contain proteins not listed on the label - soy is a common one - and these proteins would confound our evaluation of the efficacy of the hypoallergenic diet. The prescription foods are available from his vet. There are many novel protein foods and a prototypical hydrolyzed protein food is Hill’s Prescription Diet z/d ultra (a hydrolyzed protein diet is my preference). A positive response is usually seen within a few weeks if we’ve eliminated the offending food allergen. Food intolerance can arise at any age and even after our patient has been eating the same food for quite some time.
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