Pachydermatous eosinophilic dermatitis.

We report three South African black teenage girls with extensive pruritic papular lesions arising on a pachydermatous base, resembling severe atopic dermatitis or onchodermatitis. All three had peculiar hypertrophic genital lesions and peripheral blood eosinophilia. Histological studies showed an eosinophil-rich lymphohistiocytic infiltrate and variable fibrosis. Extensive fibrillar extracellular deposition of eosinophil granule major basic protein was demonstrated by an indirect immunofluorescence technique. A beneficial therapeutic effect was obtained using dapsone, prednisolone and cetirizine. The term pachydermatous eosinophilic dermatitis is proposed and its position among other conditions characterized by peripheral blood and skin tissue eosinophilia, is discussed.