Recent advances in nontuberculous mycobacterial lung infections.

Nontuberculous mycobacteria (NTM) are members of the Mycobacterium genus other than Mycobacterium tuberculosis complex and Mycobacterium leprae. NTM are widely distributed in the environment and are increasingly recognized as causes of chronic lung disease that can be challenging to treat. In this brief review, we consider recent developments in the ecology, epidemiology, natural history, and treatment of NTM lung disease with a focus on Mycobacterium avium complex (MAC) and Mycobacterium abscessus complex .