产金属β-内酰胺酶大肠埃希菌对亚胺培南的耐药性研究  

Resistance of Escherichia coli producing metallo-β-lactamases to imipenem Depnrtnlent

作　　者：郑媛媛[1] 董春忠[1] 刘学雷 王月玲[2] ZHENG Yuan-yuan;DONG Chun-zhong;LIU Xue-lei(Department of clinical laboratory,the people's hospital of Binzhoucity,Shandong Binzhou 256610)

机构地区：[1]滨州市人民医院检验科,山东滨州256610 [2]山东省立医院检验科,山东济南250013

出　　处：《医学检验与临床》2024年第12期1-8,共8页Medical Laboratory Science and Clinics

基　　金：山东省自然科学基金资助项目,项目编号:ZR2020MH306。

摘　　要：目的:分析产金属β-内酰胺酶大肠埃希菌对亚胺培南和美罗培南敏感性降低的原因。方法:用脉冲场凝胶电泳(PFGE)进行同源性分析,采用E-test方法测定菌株及接合子和转化子的药敏情况。采用RT-PCR扩增和序列分析、碳青霉烯酶抑制剂增强实验、外膜蛋白分析(SDS-PAGE)以及羰酰氰氯苯腙(CCCP)抑制试验分析大肠埃希菌对亚胺培南耐药的原因。结果:菌株Eco1、Eco2和Eco3为非同一克隆株,对亚胺培南的MIC分别为6μg/mL、16μg/mL和16μg/mL,对美罗培南的MIC分别为6μg/mL、16μg/mL和32μg/mL,对厄他培南、哌拉西林/他唑巴坦耐药、氨曲南、头孢噻肟、头孢曲松、头孢吡肟、头孢西丁、左氧氟沙星和庆大霉素均高度耐药;菌株Eco3对阿米卡星敏感,菌株Eco1和Eco2对阿米卡星高度耐药。菌株Eco1产CTX-M-79、SHV-11、IMP-4、CMY-6和NDM-1,菌株Eco2产CTX-M-79、CTX-M-14、CMY-6和NDM-1,菌株Eco3产CTX-M-14、CMY-6和IMP-4。CCCP不能提高Eco1、Eco2和Eco3对亚胺培南的敏感性,SDS-PAGE发现菌株Ompk35和Ompk36未见缺少,3株大肠埃希菌EDTA增强实验阳性。仅菌株Eco1的NDM-1金属β-内酰胺酶通过接合试验传递到大肠埃希菌J53上,其接合子对亚胺培南和美罗培南耐药,EDTA增强实验阳性;菌株Eco2接合子和转化子不含NDM-1金属β-内酰胺酶,其接合子和转化子对亚胺培南和美罗培南敏感;菌株Eco3接合试验和转化试验未成功。结论:同时产CTX-M-79、CTX-M-14、CMY-6、NDM-1、IMP-4或CTX-M-79、CTX-M-14、CMY-6、IMP-4β-内酰胺酶的大肠埃希菌可引起亚胺培南高度耐药。Objective:To analyze the reason of the decreased sensitivity of Escherichia coli producing metallo-β-lactamase to imipenem and meropenem.Methods:Homology analysis was performed by pulsed field gel electrophoresis(PFGE).E-test was used to determine the drug susceptibility of the strains,zygotes and converters.The causes of imipenem resistance of Escherichia coli were analyzed by RT-PCR amplification and sequence analysis,carbapenase inhibitor enhancement test,outer membrane protein analysis(SDS-PAGE)and carbonyl cyanchlorophenzone(CCCP)inhibition test.Results:Strains Eco1,Eco2 and Eco3 were different clones.MIC for imipenem was 6μg/mL,16μg/m and 16μg/mL,and MIC for meropenem was 6μg/mL,16μg/m and 32μg/mL,respectively.Highly resistant to ertapenem,piperacilin/Tazobactam,amtraxam,cefotaxime,ceftriaxone,cefepime,cefoxime,levofloxacin and gentamicin;Strains Eco3 were sensitive to amikacin,and strains Eco1 and Eco2 were highly resistant to amikacin.Strain Eco1 produced CTX-M-79,SHV-11,IMP-4,CIMY-6 and NDM-1,strain Eco2 produced CTX-M-79,CTX-M-14,CIMY-6 and NDM-1,and strain Eco3 produced CTX-M-14,CIMY-6 and IMP-4.CCCP could not improve the sensitivity of Eco1,Eco2 and Eco3 to imipenem.SDS-PAGE found no deficiency in Ompk35 and Ompk36 strains,and 3 strains of Ecoli were positive for EDTA enhancement.Only NDM-1 metallo-β-lactamase of strain Eco1 was transferred to Escherichia colij53 through conjugation test,and its conjugants were resistant to imipenem and meropenem,and EDTA enhancement test was positive.The zygotes and converters of the strain Eco2 did not contain NDM-1 metallo-β-lactamase,and their zygotes and converters were sensitive to imipenem and meropenem.The conjugation test and transformation test of strain Eco3 were not successful.Conclusion:E.coli producing CTX-M-79,CTX-M-14,CIMY-6,NDM-1,IMP-4 or CTX-M-79,CTX-M-14,CIMY-6,IMP-4β-lactamase at the same time can cause high resistance to imipenem.

关 键 词：大肠埃希菌 Β-内酰胺酶 外膜蛋白 碳青霉烯类 耐药性 

分 类 号：R44[医药卫生—诊断学]