唐山市碳青霉烯耐药肠杆菌科细菌分布及耐药基因检测

Distribution characteristics of carbapenem-resistant Enterobacteriaceae and analysis of drug resistance genes in Tangshan city

目的了解唐山市碳青霉烯类耐药肠杆菌科细菌(CRE)菌种分布、耐药特点及碳青霉烯酶耐药基因的主要型别,为临床合理选用抗菌药物提供依据。方法收集唐山市3家三级甲等综合医院2019年6月—2021年3月临床分离的非重复菌株CRE 152株。采用VITEK2 Compact全自动微生物分析系统对细菌进行菌种鉴定和药物敏感性检测;改良碳青霉烯类灭活试验(mCIM)和EDTA协同改良碳青霉烯类灭活试验(eCIM)对CRE进行耐药表型筛查;PCR法扩增常见的碳青霉烯酶基因blaKPC、blaIMP、blaVIM、blaNDM和blaOXA-48。结果CRE标本来源主要是痰液(36.2%)、尿液(19.7%)和分泌物(15.8%);菌种主要是肺炎克雷伯菌(74.3%)和大肠埃希菌(15.8%);143株CRE检测出碳青霉烯酶基因,blaKPC-2占74.8%,blaNDM占25.2%,1株CRE同时携带blaKPC-2和blaNDM;CRE仅对替加环素高度敏感,对临床常用抗菌药物耐药率超过80%。结论唐山市CRE主要来自呼吸道和泌尿道,菌种以肺炎克雷伯菌为主,耐药基因主要是blaKPC-2和blaNDM,表现为多重耐药。

Objective To investigate the distribution and characteristics of carbapenem-resistant Enterobacteriaceae(CRE)and the main types of carbapenemase resistance genes in Tangshan,so as to provide a basis for the rational selection of antimicrobial drugs in clinical practice.Methods A total of 152 CRE were isolated from 3 tertiary hospitals in Tangshan city from 2019 to 2021.Vitek 2 Compact was used for bacterial identification and drug sensitivity testing.The modified carbapenem inactivation test and EDTA synergistically modified carbapenem inactivation test were used for phenotypic screening to predict the type of carbapenemase produced by CRE.The common carbapenemase genes blaKPC,blaIMP,blaVIM,blaNDM and blaOXA-48 amplificated by PCR method,and the products were sequenced.Results The main sources of CRE specimens were sputum(36.2%),urine(19.7%)and secretion(15.8%).The strains were mainly K.pneumoniae(74.3%)and E.coli(15.8%).Carbonapenase gene was detected in 143 CRE strains,74.8%of which were blakPC-2 and 25.2%of which were blaNDM.One CRE strain carried both blakPC-2 and blaNDM.CRE was only highly sensitive to tigecycline,and the drug resistance rate to commonly used antibiotics in clinical practice was>80%.Conclusion CRE stains in Tangshan city mainly are K.pneumoniae,and the drug resistance genes are mainly blakPC-2 and blaNDM,showing multiple drug resistance.