耐碳青霉烯类肠杆菌科细菌耐药基因分析

Analysis of drug resistance genes of carbapenem-resistant Enterobacteriaceae

目的 研究和探讨碳青霉烯类耐药肠杆菌科细菌(CRE)对临床常用抗菌药物敏感性和携带耐药基因型。方法 收集本院2018年1月-2019年10月临床分离CRE菌株,对其进行细菌鉴定及药敏试验,并应用PCR技术筛选bla_(KPC)、bla_(NDM)、bla_(IMP)、bla_(VIM)、bla_(OXA-48)、bla_(CTX-M)、bla_(SHV)、bla_(TEM)基因,扩增产物纯化后进行测序,经BLAST比对,得到耐药基因型。结果 60株CRE菌株对替加环素耐药率为3. 3%,对米诺环素耐药率为16. 7%,对复方新诺明耐药率为60. 0%,对其他药物均高度耐药(> 75%);60株碳青霉烯酶阳性57株,基因型以KPC-2(55株)为主,未检出OXA-48及VIM,其中22株同时产生2种碳青霉烯酶,35株产生一种碳青霉烯酶。所有产碳青霉烯酶肠杆菌科细菌(CPE)在携带碳青霉烯酶耐药基因同时携带了不同程度的ESBL基因。结论 本院CRE株肺炎克雷伯菌以产KPC-2为主,大肠埃希菌以产KPC-2+NDM-5为主,CPE菌株携带ESBL率为100%,60株CRE对替加环素和米诺环素耐药率较低。

Objective To study and investigate the antimicrobial resistance and resistance genes of carbapenem-resistant Enterobacteriaceae bacteria(CRE).Methods Clinical isolates of CRE were collected in our hospital from January 2018 to October 2019.Bacteria identification and drug sensitivity test were conducted.PCR was used to screen bla_(KPC),bla_(NDM),blaIMP,bla_(VIM),bla_(OXA-48),bla_(CTX-M),bla_(SHV) and bla_(TEM) genes.The amplified products were purified and sequenced,and the resistant genotypes were obtained by BLAST comparison.Results The drug resistance rates of 60 CRE strains were 3.3%to tigecycline,16.7%to minocycline,60.0%to cotrimoxazole,and highly resistant to other drugs(>75%).Of the 60 strains,57 strains were carbapenase positive,and the genotype was mainly KPC-2(55 strains).OXA-48 and VIM were not detected.Among them,22 strains produced both carbapenases and 35 strains produced one carbapenase.All carbapenemase-producing Enterobacteriaceae(CPE)bacteria carried carbapenemase-resistant genes and ESBL genes to varying degrees.Conclusion In our hospital,CRE strains of Klebsiella pneumoniae mainly produced KPC-2,Escherichia coli mainly produced KPC-2+NDM-5.The ESBL rate of CPE strains was 100%,and the drug resistance rate of 60 CRE strains to tigacycline and minocycline was low.