Species level identification of non-tuberculous mycobacteria

More than 125 species of non-tuberculous mycobacteria (NTM) has been defined recently. NTM species can be easily isolated in soil, natural or purified water sources. Although these agents are considered as pathogens in immune compromised or immune suppressed patients, rate of infection in patients with intact immune system has also increased. The clinical course and therapy can differ among different species of NTM. Cheap, fast and simple methods in identification of NTM species should be helpful to eliminate the pathogens cost effectively.In this study, 156 isolates of NTM collected from respiratory tract between 2004 and 2010 in Dokuz Eylul University Central Laboratory have been studied. PCR-restriction enzyme analysis (PRA) targeting hsp65 gene location has been used to identify NTM species.In our study, distribution of the identified species were as follows; Mycobacterium abscessus type 1 (69/156), Mycobacterium xenopi (26/156), Mycobacterium fortuitum (14/156), Mycobacterium porcinum type 1, Mycobacterium septicum type 1, Mycobacterium peregrinum type 2 (14/156), Mycobacterium simiae type 5, Mycobacterium lentiflavum type 1, Mycobacterium florentinum type 1 (5/156), Mycobacterium intracellulare type 1, Mycobacterium chimaera type 1 (5/156), Mycobacterium genavense type 2, M. simiae type 1 (4/156), Mycobacterium chelonae (2/156), Mycobacterium novocastrense (1/156), Mycobacterium gordonae type 6 (1/156), Mycobacterium colombiense type 1, Mycobacterium avium s. avium type 2 (1/156), Mycobacterium massiliense type 1, Mycobacterium bolletii type 1, M. abscessus type 2 (2/156), M. avium s. avium type 1, M. avium s. paratuberculosis type 1, M. avium s. silvaticum type 1 (2/156). Ten isolates of NTM could not be identified with hsp65 PRA.In conclusion, wide spread distribution of NTM species in nature causing serious infections have been increased recently. It is important to identify NTM on a species basis to supply with proper antibacterial treatment since there are certain susceptibility differences to antibacterial drugs; furthermore, the data also holds an epidemiological importance. For that manner, to identify NTM species, hsp65 PRA method is cheap, fast, reliable and simple to use in daily practice.