Western blot analysis of sera from dogs with suspected food allergy

BACKGROUND Food allergy is often suspected in dogs with clinical signs of atopic dermatitis. This diagnosis is confirmed with an elimination diet and a subsequent challenge with regular food. Laboratory tests for the diagnosis of food allergy in dogs are unreliable and/or technically difficult. Cyno-DIAL(®) is a Western blot method that might assist with the selection of an appropriate elimination diet. HYPOTHESIS/OBJECTIVES To evaluate the performance of Cyno-DIAL(®) for the selection of an elimination diet and diagnosis of food allergy. ANIMALS/METHODS Thirty eight dogs with atopic dermatitis completed an elimination diet. Combining the results of the diet trials and the challenges, 14 dogs were classified as food allergic (FA), 22 as nonfood-allergic and two as ambiguous cases. RESULTS Amongst all dogs and amongst dogs with a clinical diagnosis of FA, 3% and 7% (respectively) were positive to Royal Canin Anallergenic(®) , Vet-Concept Kanguru(®) or Vet-Concept Dog Sana(®) ; 8% and 7% to Hill's d/d Duck and Rice(®) ; 8% and 21% to Hill's z/d Ultra Allergen Free(®) ; 53% and 64% to Eukanuba Dermatosis FP(®) ; and 32% and 43% to a home-cooked diet of horse meat, potatoes and zucchini. The specificity and sensitivity of Cyno-DIAL(®) for diagnosing food allergy were 73% and 71%, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE Although Cyno-DIAL(®) was considered potentially useful for identifying appropriate foods for elimination diet trials, it cannot be recommended for the diagnosis of food allergy. The Cyno-DIAL(®) test performed better than some previously evaluated ELISA-based tests