Unusual pathogenesis of spontaneous pneumothorax secondary to Wegener's granulomatosis.

Spontaneous pneumothorax represents a rare and potentially severe complication of Wegener's granulomatosis. A 31-year-old man with Wegener's granulomatosis on immunosuppressive therapy was admitted for a right massive spontaneous pneumothorax. After chest drainage he presented with a prolonged air leak that required a surgical treatment. Histologic findings did not reveal any necrotizing granulomatous vasculitis, but only subpleural fibrous tissue. We hypothesize that pneumothorax could be related to the subpleural fibrous retraction induced by immunosuppressive therapy.