Genotyping and drug resistance analysis of Mycobacterium tuberculosis from China / 中华检验医学杂志

ABSTRACT

Objective To study the genotypes of representative Mycobacterium tuberculosis (M.tuberculosis) strains from China with spacer oligonucleotide typing (spoligotyping),and to investigate the prevalence of different genotypes TB in China,and analyse the relationship between genotype and drug resistance.Methods 4017 clinical isolates were collected by Chinese Center for Disease Control and Prevention from 2007 to 2008 in 31 provinces in China according to sampling principle of epidemiology.Drug susceptibility testing was performed using proportion method,and spoligotyping was chosen to carry out genotyping of these M.tuberculosis.In addition,chi-square test was used to compare the differences among the detection rate of different genotypes.Results Among the 4017 M.tuberculosis isolates,2500 ( 62.2％ ) isolates belonged to Beijing genotype.The percentage of Beijing genotypes in the northern of China was higher than that in the southern of China ( 76.5％ vs.53.2％,x2 =219.69,P ＜ 0.05 ),while T1 genotypes were more common in the southern China,compared with that in northern China ( 13.3％ vs.4.3％,x2 =219.69,P ＜ 0.05 ).The differences were statistically significant.The proportions of Rifampinresistant (21.7％ vs.21.7％ ),Ofloxacin-resistant (4.9％ vs.2.4％ ) and Multidrug-resistant ( 11.3％vs.7.4％ ) isolates among Beijing genotype strains were significantly higher than those among non-Beijing strains (x2 =22.10,14.42 and 14.83,respectively,P ＜ 0.05 ).Conclusions Beijing genotype was still predominant epidemic genotypes.The percentage of Beijing genotype showed difference between distinct areas,and the percentage of Beijing genotypes in northern China was higher than that in southern China.Beijing genotype strains reveal correlation with Rifampin-resistance,Ofloxacin-resistance and Multidrug-resistance.