不同地区宋内志贺菌耐药性及脉冲场凝胶电泳分型分析

Antibiotics-resistance and pulsed-field gel electrophoresis patterns of Shigella sonnei from different regions

摘要:

摘要:【目的】通过对不同地区的宋内志贺菌株进行药物敏感性检测、耐药基因的扩增以及基因分型，了解不同地区宋内志贺菌的耐药情况与流行趋势。【方法】使用微量肉汤稀释法测定了54 株宋内志贺菌对21种药物的敏感性，用PCR方法扩增相关耐药基因，利用脉冲场凝胶电泳(Pulsed Field Gel Electrophoresis，PFGE)技术进行宋内志贺菌的基因分型，最后采用BioNumerics分析软件对所有菌株进行聚类，分析其相似度。【结果】实验菌株对于甲氧苄氨嘧啶/磺胺甲噁唑、四环素、替卡西林/棒酸、氨苄西林、庆大霉素5种抗生素普遍耐药，对亚胺培南、头孢吡肟、左氟沙星、诺氟沙星、阿米卡星5种抗生素全部表现为敏感。共检测出包括blaTEM，blaCTX以及整合子在内的7 种不同的耐药基因。全部实验菌株可分为26个不同的PFGE带型，分型后表现出较高的基因同源性。宋内志贺菌的耐药性、携带基因与带型具有一定地域相关性。【结 论】目前各地区流行的宋内志贺菌株对甲氧苄氨嘧啶/磺胺甲噁唑与四环素已经普遍耐药，不同地区出现相同聚类分型的菌株表明存在跨区域流行的宋内志贺菌群。因此，加强对不同地区宋内志贺菌的监控对减少多重耐药菌株的产生具有重要意义。

关键词:关键词:宋内志贺菌，耐药性，脉冲场凝胶电泳，基因分型

Abstract:

Abstract:［Objective］ To understand the epidemic tendency and antibiotics-resistance among Shigella sonnei isolates collected from different regions by antibiotic susceptibility testing，PCＲ amplification of the resistance genes and genotyping．［Methods］ The susceptibilities to 21 antibiotics of 54 S． sonnei strains were determined by broth microdilution using a 96-well microtiter plate．The amplification of resistance genes was performed by PCR．Pulsed field gel electrophoresis genotyping method was applied to analyze their genetic relationships，and BioNumerics software was used to analyze the PFGE patterns． ［Ｒesults］ All tested S． sonnei strains were resistant to Trimethoprim/Sulfamethoxazole，Tetracycline，Ticarcillin，Ampicillin and Gentamicin，whereas sensitive to Imipenem，Cefepime，Levofloxacin，Norfloxacin and Amikacin．A total of 7 different antibiotic resistance genes including blaTEM，blaCTX and intI were identified in the multidrug-resistant S．sonneis strains．PFGE patterns of all the isolates showed a high genetic homology．［Conclusion］It is of great importance to strengthen the surveillance of S．sonnei from different regions in order to reduce the prevalence of multidrug-resistant strains.

Key words:Keywords: Shigella sonnei，antibiotic resistance，pulsed field gel electrophoresis，genotyping