Pulmonary alveolar proteinosis: successful treatment with aerosolized trypsin.

A 37 year old man with pulmonary alveolar proteinosis and severe pulmonary physiologic impairment was treated empirically for 12 months with continuous oxygen, intermittent positive pressure breathing and aerosolized saline solution, heparin and acetylcysteine. Because of progression of disease, he was treated with aerosolized trypsin in a dose of 100,000 U twice daily for six months. This treatment was associated with dramatic symptomatic, chest roentgenographic and pulmonary physiologic improvement that has lasted for two and a half years without remission. The absence of adverse effects of trypsin aerosol allowed its administration in the patient's home. It is suggested that the preferred initial therapy for symptomatic alveolar proteinosis is aerosolized trypsin.