Atopiform dermatitis.

It is proposed to introduce the term 'atopiform dermatitis' to describe patients who have dermatitis with many of the characteristics of true atopic dermatitis, but who are not atopic. Atopy should be defined as the genetically determined and environmentally influenced syndrome in which the primary immunological abnormality is the production of allergen-specific IgE. It is suggested that by making a distinction between atopiform dermatitis and true atopic dermatitis, subsequent genetic, immunological and therapeutic studies will be improved. Furthermore, atopiform dermatitis would be a more appropriate diagnosis for the atopic dermatitis-like skin diseases that may occur in syndromes such as phenylketonuria, Schwachman's syndrome, Wiskott-Aldrich syndrome, Netherton's syndrome, Job's syndrome, selective IgA deficiency, agammaglobulinaemia and ataxia telangiectasia. In contrast to patients with true atopy, patients with atopiform dermatitis can logically be advised that allergen avoidance is not required, as they have no allergen-specific IgE.