Evaluation of Polycheck test results used for causal allergen determination in canine atopic dermatitis

Abstract

Seventy-five dogs with a clinical diagnosis of canine atopic dermatitis were examined by serological allergy tests. The tests used in this study have been available in Hungary for the last two years only, and this study is the first one evaluating their results. The aim of this study was also to collect data about the most common allergens involved in the disease in Hungary and to compare them with existing publications from Europe and the rest of the world. This study was the second survey about SAT in Hungary. The most prevalent allergens were D. farinae and T. putrescentiae, with a prevalence of 94.7%, followed by flea, Acarus siro (88% each) and D. pteronyssinus (82.7%). These results, illustrating a major incidence of arthropod allergens in canine atopic dermatitis, are in accordance with many other studies and previous Hungarian results. Correlation analysis of our data has shown a breed-related variations in response to allergen testing: Golden retrievers had a high number of positive reactions to D. farinae, and L. destructor, but reaction to Malassezia was rare in that breed; Labradors has a high number of positive reactions to sorrel; Hungarian Vizslas had a high number of positive reactions to D. pteronyssinus and rye; and on the other hand, L. destructor, birch/alder/hazel, plantane/willow/poplar and grass mix were uncommon allergens in the West Highland White Terrier. This suggests the existence of breed predispositions not only to atopy in general, but also to sensitivity to one or several specific allergens in particular. However, such hypothesis should be verified in studies on a larger population in order to be validated. Our results also suggest a certain degree of resistance of mixed breed dogs to sensitivity to flea allergens, which again would require investigations on a larger scale. And at last, the suspicion of a certain level of cross-reaction between some allergens has also arisen from our results, which is a concern that has been brought up by other authors. Efforts are still required in order to increase the sensitivity and specificity of the serological allergy tests, to improve their accuracy in the evaluation of atopic patients, for both diagnostic and therapeutic purposes.