Wang Yuan-Chuan, Zhu Ru-Yi, Xu Yun-Yi, Zhao Ming-Qiu, Liu Ya-Hong, Li Bing, Chen Jin-Ding
College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.
Jpn J Infect Dis. 2009 Jul;62(4):270-4.
The aim of this study was to characterize 160 clinical Mycobacterium tuberculosis isolates from Guangdong with respect to their drug susceptibility phenotypes to three common anti-tuberculosis drugs, isoniazid (INH), rifampin (RIF) and streptomycin (SM), and with respect to genetic mutations in the most commonly corresponding resistance genes (katG, rpoB and rpsL). The drug susceptibility profiles were evaluated by the absolute concentration method, and genetic mutations in the corresponding resistance genes were identified by DNA sequencing. Among these isolates, 33.1% (53/160) were drug-resistant. The percentages of isolates resistant to INH, RIF and SM were 21.9% (35/160), 16.9% (27/160) and 15.6% (25/160), respectively. Twenty-five of 35 (71%) INH-resistant isolates, 22 of 27 (81.5%) RIF-resistant isolates and 19 of 25 (76%) SM-resistant isolates were found to have mutations in the analyzed katG, rpoB and rpsL gene fragments. The most frequent mutation patterns for the three drugs were as follows: INH, Ser315Thr (68.6%) in katG; RIF, Ser531Leu (55.6%) in rpoB; and SM, Lys43Arg (72%) in rpsL. These findings provide useful data on the mutation types of drug-resistant genes in M. tuberculosis isolates from Guangdong province in China.
本研究的目的是对来自广东的160株临床结核分枝杆菌分离株进行特征分析，包括它们对三种常见抗结核药物异烟肼（INH）、利福平（RIF）和链霉素（SM）的药敏表型，以及最常见的相应耐药基因（katG、rpoB和rpsL）中的基因突变情况。采用绝对浓度法评估药敏谱，通过DNA测序鉴定相应耐药基因中的基因突变。在这些分离株中，33.1%（53/160）对药物耐药。对INH、RIF和SM耐药的分离株百分比分别为21.9%（35/160）、16.9%（27/160）和15.6%（25/160）。在35株INH耐药分离株中有25株（71%）、27株RIF耐药分离株中有22株（81.5%）、25株SM耐药分离株中有19株（76%）在分析的katG、rpoB和rpsL基因片段中发现有突变。三种药物最常见的突变模式如下：INH，katG基因中的Ser315Thr（68.6%）；RIF，rpoB基因中的Ser531Leu（55.6%）；SM，rpsL基因中的Lys43Arg（72%）。这些发现为中国广东省结核分枝杆菌分离株耐药基因的突变类型提供了有用数据。
