Diagnostic accuracy of serum assays for mite sensitivity in dogs with atopic dermatitis

Abstract

Clinical signs of canine atopic dermatitis (AD) are usually associated with immunoglobulin-E (IgE) reactions against environmental allergens, especially house dust mites. Serological and intradermal testing are indicated for AD diagnosis, allergen control, and the selection of allergen-specific immunotherapy protocols. This study aimed to evaluate accuracy, predictive values and agreement of a FceR1-alfa serological test and a polyclonal test, compared with a highly specific intradermal test (IDT). IDT was performed on 78 dogs (55 atopic, 23 healthy). Serological tests were conducted in 20 IDT positive atopic dogs, and in 19 IDT negative healthy dogs. Polyclonal test showed an accuracy of 0.49, sensitivity (S) of 74%, specificity (E) of 26%, positive predictive value (PPV) of 50%, and negative predictive value (NPV) of 45%. For each mite, the accuracy ranged from 0.46 to 0.58, with S and E varying from 36 to 78%. FceR1-alpha test showed an accuracy of 0.46, S of 65%, E of 26%, PPV of 48%, and NPV of 42%. Agreement between the evaluated serological tests was moderate, with no agreement between these and IDT. Accuracy parameters evaluated herein, suggest that the evaluated serological tests are not recommended for selecting allergens for allergen-specific immunotherapy protocols, when using a highly specific IDT as reference.