Genotyping and molecular characteristics of multidrug-resistant Mycobacterium tuberculosis isolates from China. Issue 4 (April 2015)

• Record Type: Journal Article
• Authors: Zhang, Zhijian; Lu, Jie; Liu, Min; Wang, Yufeng; Qu, Geping; Li, Hongxia; Wang, Jichun; Pang, Yu; Liu, Changting; Zhao, Yanlin
• Is Part Of: Journal of infection. Volume 70:Issue 4(2015)
• Page Start: 335
• Page End: 345
• Publication Date: 2015-04
• Subjects: Infection -- Periodicals; Bacterial Infections -- Periodicals; Communicable Diseases -- Periodicals; Electronic journals; 616.905
• DOI: 10.1016/j.jinf.2014.11.008
• Languages: English
• ISSNs: 0163-4453

Abstract

<abstract xml:lang="en" abstract-type="author" id="abs0010"> <title id="sectitle0010">Summary</title> <sec> <title id="sectitle0015">Objectives</title> <p id="abspara0010">The aim of this study was to explore the population structure of multidrug-resistant (MDR) tuberculosis strains and distribution of resistance-associated nucleotide alteration among the different genotype MDR strains in China.</p> </sec> <sec> <title id="sectitle0020">Methods</title> <p id="abspara0015">The genotypes of 376 MDR strain were analyzed by 15-loci MIRU-VNTR and RD105 deletion-targeted multiplex PCR (DTM-PCR) method. In addition, all the MDR isolates were sequenced for genetic mutations conferring rifampicin (<italic>rpoB</italic>) and isonizid resistance (<italic>katG</italic>, <italic>inhA</italic> and <italic>oxyR</italic>-<italic>ahpC</italic>).</p> </sec> <sec> <title id="sectitle0025">Results</title> <p id="abspara0020">Among the 376 MDR isolates, 261 (69.4%) belonged to Beijing genotype, including 177 modern Beijing strains (67.8%) and 84 ancient Beijing (32.2%) strains. The percentages of streptomycin-resistant, kanamycin-resistant, pre-XDR and XDR TB in modern Beijing genotype were significantly lower than ancient genotype (<italic>P</italic> < 0.05). The Beijing MDR strains had significantly higher proportions of ofloxacin-resistant and pre-XDR isolates than non-Beijing strains (<italic>P</italic> < 0.01). In addition, the clustering rate of modern Beijing strains was significantly higher than that of ancient Beijing strains (46.3% vs. 11.9%, <italic>P</italic> < 0.01). 94.7% and 79.3% of MDR isolates harbored genetic mutations conferring rifampicin and isonizid resistance, respectively, and the most prevalent mutation was located in codon <italic>rpoB531</italic> and <italic>katG315</italic>. In addition, the <italic>rpoB</italic>531 and <italic>katG</italic> mutation were more frequently observed among Beijing genotype strains than non-Beijing strains, while non-Beijing genotype showed stronger association with isolates lacking mutation in rifampicin resistance determination region (<italic>P</italic> < 0.05).</p> </sec> <sec> <title id="sectitle0030">Conclusions</title> <p id="abspara0025">Our findings demonstrated that ancient Beijing MDR strains were associated with drug resistance, while modern Beijing MDR strains were more likely to be clustered.</p> </sec> </abstract>