| Objective To obtain the bacterial species and frequency of Mycobacterial infections in individuals infected with HIV/AIDS, and analyse the virulence and the frequency of gene mutation related to drug resistance of Mycobacterium tuberculosis isolated from these patients.Methods Conservative sequences(hsp65) were amplified by PCR with mycobacteria universal primers, followed by DNA sequencing and comparative analysis using Basic BLAST program. Nested PCR was used in the detection of mycobacterium tuberculosis drug resistance gene to identify frequency of gene mutation corresponding to drug susceptibility to first line anti-TB drugs. RD105deletion was used to investigate the proportion of Beijing/W strains in Mycobacterium tuberculosis isolated from patients with HIV/AIDS.Results Overall,244of326patients (74.8%) were positive and82patients (25.2%) were negative by PCR. Among244strains based on DNA sequencing, M.tuberculosis were isolated in167(68.4%) strains, nontuberculous mycobacteria (NTM) were77(31.6%). Among nontuberculous mycobacteria (NTM), M.gordonae were39, Mycobacterium avium-intracellulare complex were18, M. kansasii were12, M. abscessus were3,M. fortuitum were2, M. massiliense were2, M. xenopi was one Except inhA, the rest six genes have gene mutations. Each gene mutation rate of rpoB, katQ embB, rpsL, rrs and pncA were11.9%,7.7%,3.8%,7.7%,4.8%and6.1%, respectively. Beijing/W strains of Mycobacterium tuberculosis were isolated in63cases of82(76.8%) strains, non-Beijing/W strains of M. tuberculosis were19(23.2%).Conclusion Mycobacterial infections are frequent opportunistic infections in patients with HIV/AIDS. M. tuberculosis, Mycobacterium avium complex and M. kansasii are common strains. RpoB, katQ embB, rpsL, RRS and pncA of mycobacterium tuberculosis associated with drug resistance showed different gene mutation rate. Beijing/W strains of M. tuberculosis, which are kown as stronger virulence strains, were the majority type.
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