Current Situations on Identification of Nontuberculous Mycobacteria

Non-tuberculous mycobacteria (NTM) cause diseases in both immuno-compromised and immuno-competent patients. Besides sputa, the NTM infections are also identified in nodes, pleura, and osteoarticular. Isolation rate of NTM has been increasing during recent years, ranging between 30-50% among mycobacterial isolates. Although the clinical significance remains to be continuously evaluated, emerging NTM infections are frequently reported. Traditional clinical assessments, acid fast bacilli staining (AFB), and culture methods accompanied with biochemical identifications will gradually not be able to cope with the clinical requirements. Instead, specific in vitro DNA amplification and/or nucleic acid hybridization-based detection systems including (real-time) PCR, chips, arrays, or liquid detection systems, together with new next-generation nucleic acid sequencing technology will gradually replace traditional diagnostic methods in NTM identification. The aim of this article is to provide a general overview on clinical significance, classification, and laboratory diagnostic methods of NTM.