Application of patch test in allergic (atopic) dogs and investigation of dog allergy incidence in people

Abstract

Incidence of canine allergic contact dermatitis (ACD) is difficult to determine, although it is regularly encountered in veterinary practice. Patch testing is a non-invasive method of determining contact allergens that may cause eczematous skin eruptions in dogs, although standardization of the procedure is yet to be completed. The aim of the present study was to determine the frequency of contact sensitizations in dogs with dermatitis, to interpret the results from standardized allergens, and to evaluate their clinical relevance. Sensitivity to pet animals is a frequent cause of allergic symptoms in atopic human patients and/or patients with asthma. Therefore, we also try to determine the possible allergic hypersensitivity of dog owners to their own dogs. European patch test standard serial was applied to 22 allergic dogs. Test results were positive in 9 (41%) dogs with allergic dermatitis. Nickel sulphate, potassium dichromate, bis-diethydithiocarbamato-zinc, p-t-butylph.-formaldehyde-resin, fragrance mix, benzocame, ammoniated mercury, mercapto mix and Cetylstearylalcohol were the positive allergens determined. Specific IgE (dog epithelium and dandruff) floroenzymeimmunoassay was applied to blood samples of dog owners (n = 12), as well as to a control group of non-owners (n = 10). Although the dog owners were not demonstrating any signs of allergic symptoms, they all were positive for specific IgE. On the other hand, in the control group, only 4 people (40%) were positive with specific IgE. Our data suggest that complete avoidance of dog antigen may not be possible. Moreover, these findings support the potential involvement of contact allergens in dogs with atopic dermatitis.