The ACVD task force on canine atopic dermatitis (VI): IgE-induced immediate and late-phase reactions, two inflammatory sequences at sites of intradermal allergen injections

Intradermal testing is a common diagnostic procedure used in the evaluation of dogs with suspect-ed atopic dermatitis (AD). To do this, most investiga tors assess the appearance of wheals that develop at the sites of intraderm al allergen injections. However, wheals are rarely seen in dogs with natura lly occurring AD. Furthermore, infiltration of inflammatory cells into the injection sites can occur 6-24 h later, a phenomenon known as the late-phas e reaction. The histological appearance of these late-phase reactions close ly approximates that seen in the natural disease, suggesting that they mi-h t be more relevant than the immediate reactions. In this paper, we review t he literature on immediate and late-phase reactions and re-assess the evide nce for using current intradermal testing procedures as a diagnostic test i n dogs. (C) 2001 Elsevier Science B.V. All rights reserved.