Allergen sensitization patterns of allergic dogs: IgE-microarray analysis

Abstract

It was the aim of this study to determine sensitization rates to environmental allergens in 50 dogs with allergic dermatitis. Protein microarray of the dogs' sera was used to identify allergen-specific IgE against 25 most common allergens. Increased IgE levels were most frequently observed for house dust mites (D. pteronyssinus 42.0%, D. farinae 38.0%) and storage mites (22-50%). In particular, the dogs with non-food-induced allergic dermatitis showed higher sensitization rates to mites compared to the dogs with food-induced allergic dermatitis, or a combination thereof. Reactions to insects were, with the exception of one dog sensitized to cockroach, entirely negative, and variable for epithelia (wool, 2-10%; cow, 36%; mixed feathers, 2%). Clinicians should consider testing these allergens only if there is a clear history of exposure. In this study 18 out of 50 dogs with AD had Malassezia infection based on cytology, but only 2 dogs showed elevated levels of Malassezia-specific IgE. Although their clinical significance was unclear, reactions to Alternaria and Aspergillus sp. were more common (10.0 and 18.0%, respectively). With the exception of Eucalyptus sp. allergen, sensitization was noticed to all tested pollen, but most commonly observed to grasses: Poa pratensis (22%) and Cynodon dactylon (20%). It is concluded that the fluorescence-linked immunosorbent protein array can be successfully used to identify sensitization. Careful selection of dogs with allergic dermatitis by means of Favrot's diagnostic criteria is important, as the results may be the basis for subsequent immunotherapy.