Spontaneous pneumothorax in patients with acquired immunodeficiency syndrome treated with prophylactic aerosolized pentamidine.

Spontaneous pneumothorax is a known complication of Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome. To evaluate the possible pathogenesis and natural history of pneumothorax in patients receiving aerosolized pentamidine prophylaxis, we retrospectively reviewed 327 outpatients positive for human immunodeficiency virus receiving aerosolized pentamidine. There were 12 spontaneous pneumothoraces in this group of patients. Seventy-five percent of patients with pneumothorax had roentgenographic evidence of fibrocystic lung parenchyma and clinical evidence of active Pneumocystis pneumonia. The majority (83%) required chest tube evacuation. There was a 50% mortality rate associated with this complication. These findings suggest that spontaneous pneumothorax in patients treated with aerosolized pentamidine most commonly represents a prophylaxis failure associated with a high mortality rate.