THE ATOPY PATCH TEST - AN INCREASED RATE OF REACTIVITY IN PATIENTS WHO HAVE AN AIR-EXPOSED PATTERN OF ATOPIC ECZEMA

In a subgroup of patients with atopic eczema (AE), eczematous skin les ions can be induced by epicutaneous testing with aeroallergens (the at opy patch test: APT). An increased frequency of positive APT has been found in AE patients showing a predictive lesional pattern affecting a ir-exposed skin areas. This study investigates the dose-response of th e APT in two different patient groups with AE. Petrolatum preparations of house dust mite, cat dander and grass pollen allergens in four con centrations (500-10,000 protein nitrogen units) were tested epicutaneo usly in 57 patients with AE, who were prospectively divided in two gro ups according to whether their AE pattern was with (group I) or withou t (group IT) a predictive distribution. Sixty-nine per cent of patient s in group I, and 39% in group II, had positive APT reactions (P = 0.0 2). The reactions in group I were elicitable with lower allergen conce ntrations (P = 0.03). A clinically recognizable subgroup of patients w ith AE showed increased cutaneous sensitivity to aeroallergens.