Immediate reactions following challenge-tests in children with atopic dermatitis.

It has been shown that atopic dermatitis improves in children when certain foods are eliminated from the diet. Because of the unreliability of the history and the low sensibility of the total and specific IgE and skin tests, at present the elimination-provocation test is the most definitive means to establish which are the offending food(s). Although many authors claim that reactions following the challenge test in atopic dermatitis are only of the delayed type, others assert that immediate reactions are frequent and can sometimes threaten life. The pathogenesis of such reactions is not yet completely understood. However, it has been suggested that a direct IgE-mediated mechanism, inducing a release of anaphylactic mediators, could play some role. The aim of our study is to investigate the incidence of immediate reactions which can follow the food challenge in children with atopic dermatitis who have never experienced such reactions and, in addition, to investigate the reliability of total and specific IgE and skin tests in predicting immediate reactions after the challenge test. Our preliminary data indicate that immediate reactions following food challenge are frequent. Moreover they can be severe and cannot be predicted by the history, by the total and specific IgE levels and by the skin tests' results.