Species distribution of Non tuberculosis mycobacteria isolates from North of Iran

Abstract

Nontuberculous mycobacteria (NTM) differ from tuberculous mycobacteria as most of them are ubiquitous and saprophytic. A few are considered to have the potential to infect humans. The immunological status of a person determines the advance of disease. On the other hand among environmental factors, water plays the main roles as a resource of contamination in transferring this group of microorganisms to human. The aim of this study is to identify and isolate NTM in the different region of Iran surface water. 62 water samples were collected from different regions of Northern Iran. Cetyl pyridinium chloride (cpc) 0.01% was used to decontaminate the water samples. After enrichment using filtration, all samples were incubated on Lowenstein-Jensen (LJ) medium at temperatures of 30 and 37 °C. Classical culture, biochemical and enzymatic methods are described for the identification of mycobacteria. hsp65 gene has more variability in its sequences, compared to the some more conserved genes in NTM, for identification of mycobacteria to species level. A 441 bp fragment of hsp65 genes was amplified and digested by two restriction enzymes, BstEII and HaeIII. Digested products were analyzed using 3% agarose gel electrophoresis. from the total of 62 water samples, 8(50%) mycobacteria have been isolated. There were different hsp65 gene PCR-RFLP profiles produced by digestion with BstEII and HaeIII. Dominant isolates were M. fortuitum. Other isolates of Mycobacteria were differentiated using hsp65 genes PCR-RFLP. This study indicates that notable percentage of water sources are contaminated with mycobacterium species. The exposure of immunocompromised individuals to these sources can have crucial consequences. Interestingly the prevalence of mycobacterium species differs in diverse geographical areas.