Abstract
Cutaneous alterations that can occur in the following systemic granulomatous diseases are described: histiocytosis X, nevoxantho-endothelioma, multicentric reticulohistiocytosis, allergic granulomatosis, Wegener's granuloma, sarcoidosis, leprosy and tuberculosis. A classification of cutaneous reactions to the tubercle bacillus is incorporated in the discussion of tuberculosis.