Skin and Soft Tissue Infections Due to Nontuberculous Mycobacteria.

PURPOSE OF REVIEW This review describes recent trends in the epidemiology of nontuberculous mycobacteria (NTM), emerging pathogens, new insights into NTM pathogenesis, and advances in diagnosis and treatment. RECENT FINDINGS Emerging pathogens include Mycobacterium chimaera and drug-resistant subspecies of Mycobacterium abscessus. Important virulence mechanisms of pathogenic NTM include the ability to alter the macrophage's permissiveness to intracellular bacterial growth. New diagnostic tools consist of DNA probes, gene sequencing, and matrix-assisted laser desorption ionization-time of flight. These methods allow rapid speciation of NTM species, in some cases directly from patient samples. There are few novel agents available to treat NTM, although some repurposed drugs show excellent activity. The incidence of NTM infections appears to be increasing in a number of regions around the world. Molecular methods are now the diagnostic tools of choice. Discovery of novel effective agents and/or drug combinations with greater likelihood of cure, shorter treatment duration, and fewer side effects are research priorities.