[Dermatoses with transepithelial perforation (author's transl)].

The histologic concept of epidermal elimination of particulate matter was formulated by Pinkus in 1954. Mehregan enlarged on this by recognizing its fundamental role in a variety of skin diseases. The importance of this epidermal reaction pattern in five "perforating" dermatoses is stressed. Also, it is shown that active participation of the corium and epithelio-mesenchymal interaction are required for the iniation of this mechanism. The histological differentiation and histogenesis of the presented dermatoses are discussed.