大肠埃希菌耐药基因的聚合酶链反应分析  

Polymerase-chain-reaction of drug resistance genes in Escherichia coli

作　　者：安军 周庆元 房卿 白燕 蔡挺[2] 

机构地区：[1]汉中市3201医院呼吸内科,陕西汉中723000 [2]宁波市第二医院,浙江宁波315010

出　　处：《中华医院感染学杂志》2015年第1期22-23,36,共3页Chinese Journal of Nosocomiology

基　　金：浙江省医药卫生科学研究基金资助项目(2009A184);宁波市农业与社发择优委托基金项目(2010C50038)

摘　　要：目的了解临床分离大肠埃希菌中碳青霉烯酶的携带及耐药基因分布,为临床合理应用抗菌药物提供科学依据。方法采用VITEK-2型全自动微生物检测系统鉴定细菌,用微量稀释法筛选耐碳青霉烯类大肠埃希菌30株,通过Hodge试验检测碳青霉烯酶,以EDTA/IMP、EDTA/CAZ复合纸片,亚胺培南和头孢他啶为底物,进行协同试验检测B类碳青霉烯酶(金属酶),用聚合酶链反应(PCR)扩增耐碳青霉烯类抗菌药物的基因,以确定基因的种类。结果 25株大肠埃希菌对头孢菌素、碳青霉烯类和喹诺酮类抗菌药物耐药,5株大肠埃希菌对阿米卡星敏感;通过Hodge试验对30株大肠埃希菌表型的筛选,阳性菌株共28株,阳性率为93.0%;通过PCR基因分析,30株大肠埃希菌中检出28株KPC基因,阳性率达到93.0%,30株大肠埃希菌中未发现VIM和IMP基因。结论耐碳青霉烯类抗菌药物的大肠埃希菌主要在ICU和呼吸科,耐药原因主要是KPC基因,但是不能排除VIM和IMP基因。OBJECTIVE To investigate the carbapenemases and distribution of drug resistance genes in clinical iso-lates of Escherichia coli so as to provide guidance for reasonable clinical use of antibiotics.METHODS The bacte-rial identification was conducted by using VITEK-2 automatic microorganism detection system,30 strains of car-bapenem-resistant Escherichia coli were screened with the use of micro-dilution method,the carbapenemases were detected through Hodge test,the synergy test was carried out to detect the type B carbapenemases （metallo）by u-sing the EDTA/IMP,EDTA/CAZ complex paper and imipenem and ceftazidime as substrates,and the carbapen-em-resistant genes were amplified by using polymerase-chain-reaction （PCR）so as to determine the genotype.RE-SULTS All the 25 strains of E.coli were resistant to cephalosporins,carbapenems,and fluoroquinolones;5 strains of E.coli were susceptible to amikacin.Totally 28 strains were tested positive through the Hodge testing for screening of phenotypes of 30 E.coli strains.The PCR gene analysis indicated that 28 of 30 E.coli strains car-ried with KPC gene with the positive rate of 93.0% and that neither VIM nor IPM gene was found in the 30 strains.CONCLUSIONS The carbapenem-resistant strains mainly distribute in the ICU and respiratory depart-ment.The KPC gene is the leading cause of the drug resistance,however,the VIM and IMP gene can not be ex-cluded.

关 键 词：大肠埃希菌 聚合酶链反应 KPC基因 多药耐药 

分 类 号：R378.21[医药卫生—病原生物学]