The mycobacteriology of non-tuberculous mycobacteria.

The genus Mycobacterium consists of >50 species that have been associated with human disease. Mycobacterium are categorised into M. tuberculosis and NTM that are also subdivided into rapid growers and non-rapid growers. Five major clinical syndromes have been described that are attributable to mycobacterium. These include: pulmonary disease; lymphadenitis; skin, soft tissue, and skeletal infections; catheter-related blood-stream infections in immunocompromised hosts; and disseminated disease in persons with AIDS. There is very limited documentation of person-to-person transmission of NTM. Nosocomial infections and outbreaks caused by inadequate disinfection/sterilisation of medical devices or environmental contamination of medications or medical devices are well described. Staining for AFB, culture, histopathologic, or genetic amplification technologies are used to detect and identify mycobacterium. Pulsed- field gel electrophoresis is the method of choice to determine strain relatedness. At present, susceptibility testing for non-tuberculous mycobacteria is not fully standardised and has not been correlated with clinical outcomes.