ABSTRACT
Objective To evaluate the application of MIRU - VNTR analysis in genotyping of the ofloxacin - resistant mycobacterium tuberculosis in Hangzhou. Methods From April 2010 to June 2012,the clinical isolates of mycobacterium tuberculosis were collected from designated TB hospitals in Hangzhou for drug sensitivity test. The ofloxacin -resistant mycobacterium tuberculosis strains were typed with RD105 deletion test and MIRU-VNTR typing method respectively,and the results from both methods were compared. Results A total of 52 ofloxacin -resistant mycobacterium tuberculosis strains were collected. Using RD105 deletion test,43 strains(82. 69%)belonged to mycobacterium tuberculosis Beijing family. Using a 12-locus MIRU-VNTR typing,52 distinct MIRU-VNTR patterns were detected in the 52 ofloxacin-resistant strains. The Hunter-Gaston discriminatory index(HGI)was 0. 999. Except MIRU40 and ETR-F,the other 10 MIRU-VNTR loci showed moderate or high discriminatory power for both Beijing genotype isolates and non -Beijing genotype isolates. Conclusion The selected 10 MIRU-VNTR loci has a higher discriminatory power and are appropriate for the ofloxacin-resistant mycobacterium tuberculosis genotyping.