Blastomycosis as an etiology of acute lung injury.

Blastomyces dermatitidis, a dimorphic broad-based budding yeast endemic to the Mississippi River Valley region, is responsible for morbidity in humans via inhalation and dissemination. The response of acute lung injury, which produces an illness with serious morbidity and an approximately 50% mortality, uncommonly occurs. Diagnosis can be difficult, and a high index of suspicion should be maintained in endemic regions for patients with acute lung injury of uncertain etiology, especially if their condition deteriorates on broad-spectrum antimicrobial and antitubercular therapy and they have a previous insidious respiratory complaint and constitutional symptoms. Diagnosis should be aggressively pursued and treatment with amphotericin B (0.6 to 0.8 mg/kg/day) initiated as early as possible.