检验医学 ›› 2014, Vol. 29 ›› Issue (6): 646-650.DOI: 10.3969/j.issn.1673-8640.2014.06.016

• 临床应用研究·论著 • 上一篇    下一篇

临床分离的美罗培南和环丙沙星共同耐药的铜绿假单胞菌耐药机制的研究

张国栋1,王莹2,朱红胜1   

  1. 1. 南京医科大学附属苏州医院,苏州市立医院(东区)检验科,江苏 苏州 215001;
    2. 南京市浦口区疾病预防控制中心,江苏 南京 210031
  • 收稿日期:2013-07-20 出版日期:2014-06-30 发布日期:2014-06-23
  • 通讯作者: 朱红胜, 联系电话:0512-62364338。
  • 作者简介:张国栋,男,1981年生,学士,主管技师,主要从事临床微生物检验工作。

Research on the drug resistance mechanisms of meropenem and ciprofloxacin in clinical isolates of Pseudomonas aeruginosa

ZHANG Guodong1, WANG Ying2, ZHU Hongsheng1   

  1. 1. Department of Clinical Laboratory, the Affiliated Suzhou Municipal Hospital(East-Section) of Nanjing Medical University, Jiangsu Suzhou 215001, China;
    2. Pukou District Center for Disease Control and Prevention, Jiangsu Nanjing 210031, China
  • Received:2013-07-20 Online:2014-06-30 Published:2014-06-23

摘要: 目的 探讨临床分离的对美罗培南和环丙沙星均耐药的铜绿假单胞菌的耐药机制。方法 收集经VITEK-2 Compact微生物分析系统检测为美罗培南和环丙沙星耐药的铜绿假单胞菌30株,琼脂稀释法复查最小抑菌浓度(MIC)值。改良三维试验检测碳青霉烯酶,聚合酶链反应(PCR)扩增耐药基因,逆转录PCR 分析细菌外排系统表达情况。结果 琼脂稀释法与VITEK-2 Compact微生物分析系统检测结果相同。所有菌株均未产碳青霉烯酶,PCR扩增测序未发现基因改变,逆转录PCR检测外排系统发现以mexX和mexC基因表达增加为主,其调控基因扩增测序发现4株mexC过度表达的调控基因nfxB Gly→Val(GGC→GTC),6株mexX过度表达的调控基因mexZ Val→Gly(CTG→CAG)。结论 外排系统调控基因突变而引起的外排系统MexXY-OprM和MexCD-OprJ过度表达是引起美罗培南和环丙沙星耐药的主要原因。

关键词: 铜绿假单胞菌, 耐药机制, 美罗培南, 环丙沙星, 外排系统

Abstract: Objective To investigate the drug resistance mechanisms of both meropenem and ciprofloxacin in clinical isolates of Pseudomonas aeruginosa. Methods A total of 30 isolates of Pseudomonas aeruginosa which had been tested resistance to both meropenem and ciprofloxacin by VITEK-2 Compact were collected. Agar dilution method was used to reexamine the minimal inhibitory concentrations (MIC) of meropenem and ciprofloxacin. Carbapenemases were detected by modified three-dimensional test. The resistance genes were analyzed by polymerase chain reaction (PCR) amplification. The expression of efflux systems was analyzed by reverse transcription PCR. Results The same results were showed between agar dilution method and VITEK-2 Compact. Carbapenemases were not detected by modified three-dimensional test. The overexpression ofmexX and mexC genes were detected by reverse transcription PCR. The sequencing of regulatory genes showed that there were 4 isolates which the Gly(GGC) of nfxB was substitute for Val(GTC) and 6 isolates which the Val(CTG)of mexZ was substitute for Gly (CAG). Conclusions The overexpression of the MexXY-OprM and MexCD-OprJ efflux system, due to the mutation of regulatory genes of efflux system, is contributed to the drug resistance to both meropenem and ciprofloxacin of Pseudomonas aeruginosa.

Key words: Pseudomonas aeruginosa, Drug resistance mechanism, Meropenem, Ciprofloxacin, Efflux system

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