碳青霉烯类耐药肠杆菌科细菌耐药基因分型与临床感染分析

Genotyping and clinical infection of carbapenem resistant Enterobacteriaceae

目的分析碳青霉烯类耐药肠杆菌科细菌(CRE)的流行分布、耐药情况与耐药基因分型,为临床合理用药与院感防控提供依据。方法收集2016-2020年唐山市人民医院临床分离的84株CRE临床分离菌株及其临床资料。进行体外药物敏感试验。对常见耐药基因bla_(KPC)、bla_(VIM)、bla_(IMP)、bla_(NDM)、bla_(OXA-48)进行PCR扩增检测与序列分析,确定耐药菌株耐药表型与耐药基因分型。结果共收集84株CRE菌株,其中肺炎克雷伯菌47株,阴沟肠杆菌13株,大肠埃希菌12株,产气克雷伯菌8株,产酸克雷伯菌3株,异栖克雷伯菌1株。菌株来源于7个科室,重症监护室为主要来源科室(47株),呼吸道标本为主要分离标本(67株)。体外药敏试验结果显示,所有菌株均表现对β-内酰胺酶类、喹诺酮类、四环素类药物耐药,阿米卡星、氨苄西林/舒巴坦与复方新诺明对部分菌株有一定体外抗菌活性。不同菌属之间耐药谱有部分差异。54株CRE菌株携带bla_(KPC-2),占64.3%(54/84),15株携带bla_(NDM-1),占17.9%(15/84),9株携带bla_(OXA-48),占10.7%(9/84),各1株携带bla_(IMP)与bla_(VIM)。此外有4株CRE菌株同时检出多种耐药基因。结论本院CRE菌株以肺炎克雷伯菌和阴沟肠杆菌为主,前者主要携带bla_(KPC-2)基因,后者主要携带bla_(NDM-1)基因。应对CRE菌株和主要耐药基因进行流行病学监测,控制CRE菌株的院内传播流行。

Objective To analyze the prevalence,drug resistance and genotyping of carbapenem resistant Enterobacteriaceae(CRE),so as to provide basis for clinical rational drug use and nosocomial infection prevention and control.Methods The clinical isolates of CRE in Tangshan People’s Hospital from 2016 to 2020 were collected and analyzed.The common drug resistance genes bla_(KPC),bla_(VIM),bla_(IMP),bla_(NDM)and bla_(OXA-48)were amplified and sequenced by PCR to determine the drug resistance genotypes.Results A total of 84 strains of CRE were collected in this study,including 47strains of Klebsiella pneumoniae,13 strains of Enterobacter cloacae,12 strains of Escherichia coli,8 strains of Klebsiella aerogenes,3 strains of Klebsiella oxytoca and 1 strain of Klebsiella variicola.The strains came from 7 departments,ICU was the main source department(47 strains),and respiratory specimens were the main isolated samples(67 strains).The results of antimicrobial susceptibility test showed that all strains were resistant toβ-lactam antibiotics,quinolones and tetracycline.Amikacin,ampicillin/sulbactam and cotrimoxazole have a certain antibacterial activity against some strains.There were some differences in drug resistance spectrum among different bacteria.There were 54 CRE strains carried bla_(KPC-2)gene,accounting for 64.3%(54/84),15 CRE strains carried bla_(NDM-1)gene,accounting for 17.9%(15/84),9 CRE strains carried bla_(OXA-48)gene,accounting for 10.7%(9/84),1 CRE strain carried bla_(IMP)gene,and 1 CRE strain carried bla_(VIM)gene.In addition,4 strains of CRE were found to have multiple drug resistance genes at the same time.Conclusions Klebsiella pneumoniae and Enterobacter cloacae were the main strains of CRE in our hospital.Klebsiella pneumoniae mainly carried bla_(KPC-2)gene,and Enterobacter cloacae mainly carried bla_(NDM-1)gene.Monitor of epidemiology of CRE strains and major drug resistance genes should be carried out to control the nosocomial transmission of CRE strains.