耐碳青霉烯类大肠埃希菌耐药基因检测及同源性分析  

Analysis of drug resistance genes and homology of carbapenem-resistant Escherichia coli

作　　者：于江[1] 刘元元[1] 李晓哲[1] 金呈强[1] YU Jiang;LIU Yuanyuan;LI Xiaozhe;JIN Chengqiang(Department of Clinical Laboratory,Affiliated Hospital of Jining Medical University,Jining 272000,Shandong,China)

机构地区：[1]济宁医学院附属医院检验科,山东济宁272000

出　　处：《中国现代医生》2023年第25期69-73,78,共6页China Modern Doctor

摘　　要：目的探讨耐碳青霉烯类大肠埃希菌(carbapenem-resistan Escherichia coli,CREco)的耐药基因分布情况,并进行同源性分析,为细菌感染的治疗和预防其传播提供理论依据。方法自2016年1月至2022年7月济宁医学院附属医院住院患者分离出的大肠埃希菌1311株中筛选出CREco 16株。最低抑菌浓度法进行药敏试验,聚合酶链反应(polymerase chain reaction,PCR)扩增碳青霉烯酶基因及喹诺酮类耐药基因,对阳性基因进行测序比对,用脉冲场凝胶电泳检测菌株间的同源性。结果16株CREco仅对个别抗生素敏感,对多数抗生素表现为耐药,其中对β-内酰胺类和喹诺酮类耐药率最高。经PCR扩增发现,100%携带碳青霉烯酶基因,包括NDM-1型13株,NDM-5型3株,KPC-2型8株,未检测出OXA、IMP和VIM。喹诺酮类耐药基因中,5株扩增出qnrS基因,14株扩增出aac(6’)-Ib基因。脉冲场凝胶电泳分型共获得12种谱型,C谱型最多,为流行谱型。结论CREco耐药形势严峻。碳青霉烯酶以NDM-1最常见,其次为KPC-2。喹诺酮类耐药基因aac(6’)-Ib阳性率最高。脉冲场凝胶电泳分型呈现多态性,C谱型在院内存在流行趋势。应加强CREco耐药基因的监测,采取感染控制措施以帮助遏制耐药菌的传播。Objective To investigate the distribution of drug resistance genes in carbapenem-resistant Escherichia coli(CREco)and analyze homology,so as to provide theoretical basis for the treatment and prevention of bacterial infection.Methods Sixteen CREco strains were selected from 1311 trains of Escherichia coli from inpatients in Affiliated Hospital of Jining Medical University from January 2016 to July 2022.The drug sensitivity test was performed by minimum inhibitory concentration method,the carbapenemase genes and the quinolone resistance genes were amplified by polymerase chain reaction(PCR).The positive genes were sequenced,and the homology between strains was detected by pulsed field gel electrophoresis.Results The 16 strains were sensitive to only a few antibiotics and resistant to most of them,among them,the resistance rate toβ-lactams and quinolones was the highest.100%carried carbapenemase genes by PCR,including 13 strains of NDM-1,3 strains of NDM-5 and 8 strains of KPC-2.The genes of OXA,IMP and VIM were not detected.5 strains amplified the qnrS gene,14 strains amplified the aac(6’)-Ib gene among the quinolone resistance genes.A total of 12 types were obtained by pulsed field gel electrophoresis,and the C type was the most popular.Conclusion The situation of drug resistance of CREco is serious.NDM-1 was the most common carbapenemase,followed by KPC-2.The highest positive rate of quinolone resistance gene is the aac(6’)-Ib gene.Pulsed field gel electrophoresis typing showed polymorphism,and the C type was prevalent in hospital.Surveillance of CREco resistance genes should be strengthened and infection control operations should be implemented to help contain the spread of resistant bacteria.

关 键 词：大肠埃希菌 碳青霉烯酶 耐药基因型 同源性 

分 类 号：R378[医药卫生—病原生物学]