Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China.
Int J Tuberc Lung Dis. 2010 Feb;14(2):210-6.
A population-based study was performed to characterise the genotype and phenotype of drug-resistant tuberculosis (TB) in the year 2004-2005 in two Chinese rural counties with different durations of DOTS implementation, Deqing and Guanyun.
Mycobacterium tuberculosis strains were isolated from respectively 164 and 187 patients registered at local TB dispensaries of Deqing and Guanyun. Drug susceptibility profiling and DNA sequencing were performed on the isolates.
A total of 223 isolates from 223 patients were identified as resistant to first-line drugs, of which 53 were multidrug-resistant TB (MDR-TB, i.e., resistant to isoniazid [INH] and rifampicin [RMP]). Mutations in katG were identified in 81 of 131 INH-resistant isolates (61.8%), all of which harboured the mutation in codon 315. Mutations related to RMP resistance occurred mostly in codon 531, 526 and 516 of the rpoB gene. Seventy-eight of the 115 streptomycin-resistant isolates carried a mutation in the rpsL gene at codon 43 or 88. A mutation in codon 306 of embB occurred in 21 ethambutol (EMB) resistant and 19 EMB-susceptible isolates.
Our data indicated that DNA sequencing of specific codons of the rpoB gene should be effective for predicting RMP resistance and MDR-TB in rural China.
本研究通过对中国两个农村县（德清和灌云）的耐药结核分枝杆菌（TB）的基因和表型进行基于人群的研究，以描述 2004-2005 年不同实施直接督导下短程化疗（DOTS）时间的地区的耐药结核分枝杆菌的特征。
分别从德清和灌云当地结核病防治所登记的 164 名和 187 名患者中分离结核分枝杆菌菌株。对分离株进行药物敏感性分析和 DNA 测序。
共从 223 名患者的 223 个分离株中鉴定出对一线药物耐药的菌株，其中 53 株为耐多药结核分枝杆菌（MDR-TB，即异烟肼[INH]和利福平[RMP]耐药）。在 131 例 INH 耐药分离株中，有 81 例（61.8%）发现 katG 基因突变，所有突变均发生在密码子 315。rpoB 基因突变与 RMP 耐药有关，主要发生在 531、526 和 516 密码子。在 115 例链霉素耐药分离株中，有 78 例携带 rpsL 基因 43 或 88 密码子的突变。embB 基因 306 密码子的突变发生在 21 例乙胺丁醇（EMB）耐药和 19 例 EMB 敏感的分离株中。
我们的数据表明，rpoB 基因特定密码子的 DNA 测序可有效预测中国农村地区的 RMP 耐药和 MDR-TB。
