Mycobacterium avium complex pulmonary disease in immunocompetent patients.

Mycobacterium avium complex is becoming increasingly recognized as one of the most common mycobacterial pathogens in humans. It is rapidly becoming a significant cause of pulmonary disease even in those with an intact immunity. In 1997, the American Thoracic Society published recommendations for the diagnosis and treatment of nontuberculous mycobacteria. On the basis of the authors' clinical experience of the myriad presentations of pulmonary Mycobacterium avium complex disease in an immunocompetent host, a clinical classification is proposed. The current data are summarized, and a practical approach to management of the various pulmonary forms of the disease is provided.