A case of pyoderma vegetans associated with acne conglobata.

A 41-year-old man visited our clinic because of vegetating plaques resembling pemphigus vegetans on his sacral and perianal areas. He had also suffered from acne conglobata since adolescence. A biopsy specimen taken from the perianal area showed marked acanthosis, exocytosis, and inflammatory infiltrates in the dermis, but no acantholysis. Direct and indirect immunofluorescent tests were negative for anti-intercellular antibodies. Bacterial cultures from the lesions showed many different types of organisms. We diagnosed the case as pyoderma vegetans and discussed the relationship between pyoderma vegetans and other pyoderma.