Background: In recent decades, because of increasing prevalence of immunocompromised disease, non-tuberculous mycobacteria that have been known already as environmental bacteria presented as an important pathogens. In this study, the prevalence of NTM in Isfahan city water samples was determined bydifferent methods including culture methods with biochemical tests.
Materials and methods: Eighty-five water samples were collected from different sources in Isfahan, Iran. The mycobacterial isolates were identified by the growth characteristics, pigment production, semi-quantitative catalase test, Tween 80 hydrolysis, arylsulfatase test (3 and 14 days), heat-stable catalase (pH 7, 68°C), pyrazin amidase (4 and 7 days), urease, nitrate reduction test, and colony morphology.
Results: Chlorine concentrations of the samples ranged from 0 to 1.8 mg/l. Twenty-one culturable species including M. fortuitum, 23.8% (5 cases); M.smegmatis, 14.3% (3 cases); M. chelonae like organisms, M. terrae complex, M. gordonae and M. mucogenicum, 9.5% (2 cases for each species); M. avium complex, M.phlei, M. xenopi, M. fallax, and M. flavescenc 4.8% (1 case for each species) were identified.
Conclusion: The results of this study showed the incidence of different species of NTM in this geographical region in Iran. Studies show that the prevalence of immunocompromised disease is increasing in the community and it needs different treatment management strategy; therefore, the results of this study can be useful in this strategy.
Keywords: Isfahan water samples; non tuberculous mycobacterium; phenotypic characteristics.