Diagnostic Performance of Immunoglobulin E Serology, Prick Test and Patch Test With Food Allergens in Dogs With Atopic Dermatitis and Adverse Food Reactions Using the Double-Blind Placebo-Controlled Food Challenge as Gold Standard.

BACKGROUND: In dogs with adverse food reactions (AFRs), immunoglobulin (Ig)E serology, prick test and patch test with food allergens have shown variable diagnostic performance for the identification of the offending foods, when the latter were identified using open food challenges. OBJECTIVES: To evaluate the diagnostic performance of these tests in dogs with atopic dermatitis (AD) and AFRs, using the double-blind placebo-controlled food challenge (DBPCFC) as the gold standard. ANIMALS: Twelve dogs with AD and AFRs underwent DBPCFCs with eight food items. MATERIALS AND METHODS: IgE serology, prick test and patch test with the same eight food allergens were performed after the diagnosis of AD and before the diagnostic investigation for AFRs and the DBPCFCs. RESULTS: The sensitivity (3%-60.6%), specificity (54.8%-98.4%), positive predictive value (25%-66.7%) and negative predictive value (64.1%-72.3%) of the three tests and of their combination were unsatisfactory. Furthermore, their positive and negative likelihood ratio values were not in the clinically informative range, apart from the prick test having a weakly informative positive likelihood ratio value of 3.81. CONCLUSIONS AND CLINICAL RELEVANCE: Under the conditions of this study, the diagnostic performance of IgE serology, prick test and/or patch test with food allergens was poor using the DBPCFC as gold standard.