Oral lesions as the first clinical sign of microscopic polyangiitis: a case report.

Microscopic polyangiitis (MPA) is defined as a systemic necrotizing vasculitis that clinically and histologically affects small-sized vessels without granulomata. The main clinical feature of MPA is renal involvement characterized by rapidly progressing glomerulonephritis. We report a case of oral lesions, initially thought to be associated with Wegener's granulomatosis, as the first sign of MPA in an otherwise healthy man. To our knowledge, this is the first published case of MPA-associated oral lesions.