Identification of nontuberculous mycobacteria (NTM) isolated from patients from the TB hospital

Identification is fundamental in determining the clinical significance of NTM and the choice of scheme of antimicrobial chemotherapy due to the natural resistance in most species of NTM. <b>Aim:</b> Identification of NTM isolated from patients from the TB hospital in the Urals region of Russia. <b>Material and Methods:</b> In 2015-2017, 90 cultures of NTM were obtained from 60 patients. Identification of cultures was carried out by the test systems GenoType®MycobacteriumCM and GenoType®MycobacteriumAS (Hain Lifescience, Germany). <b>Results:</b> NTM isolates were obtained only once from 46 (76.7%) patients, twice – from 6 (10.0%), thrice – from 4 (6.6%), four times- from 1 (1,7%), five times– from 2 (3.3%); six times- from 1 (1,7%) patient. LPA method allowed to determine 11 species of NTMs from 51 patients: <i>M.intracellulare</i> from 12 patients, <i>M.smegmatis</i> from 8, <i>M.abscessus</i> from 7, <i>M.avium</i> from 7, <i>M.fortuitum</i> from 7, <i>M.lentiflavium</i> from 3, <i>M.xenopi</i> from 2, <i>M.gordonae</i> from 2, <i>M.chelonae</i> from 1, <i>M.goodie</i> from 1, <i>M.simiae</i> from 1. 17 isolates from 9 patients were identified as a mixture of NTM species: <i>M.intracellulare/M.smegmatis</i> from 2 patients, <i>M.smegmatis/M.avium</i> from 2, <i>M.abscessus/M.celatum</i> from 1, <i>M.fortuitum/M.smegmatis</i> from 1, <i>M.gordonae/M.celatum</i> from 1, <i>M.genavense/M.triplex</i> from 1 and <i>M.avium/M.gordonae/M.celatum</i> from 1. <b>Conclusions:</b> Clinically significant NTMs were detected in 93.3% of cases and were represented by slow-growing and fast-growing species. In 18.9% of cases, a mixture of NTMs was detected. The most frequent pathogens in TB patients are <i>M.intracellulare</i> (in 23.3% of patients), <i>M.avium</i> (16.6%), <i>M.abscessus</i> (15.0%), <i>M.fortuitum</i> (13.3%).