胃肠外科超广谱β-内酰胺酶大肠杆菌的耐药基因分型研究

Drug resistant genotype in Escherichia coli producing extended-spectrum β-lactamases in department of gastrointestinal surgery

目的通过对医院胃肠外科患者体液中超广谱β-内酰胺酶(ESBLs)大肠杆菌耐药基因分型检测,探究胃肠外科室内的耐药基因流行特点。方法收集300例在2015年8月-12月住院患者样本,通过VITEK-2Compact全自动细菌鉴定及药敏分析系统筛选高耐药ESBLs大肠杆菌;通过PCR技术对耐药基因鉴别和扩增;将耐药基因亚型测序,通过序列比对方法对耐药基因亚型进行确认。结果筛选发现120株耐药ESBLs大肠杆菌菌株;其中14株高耐药ESBLs大肠杆菌PCR鉴定发现ESBLs大肠杆菌耐药基因的主要类型是CTX-M型,测序发现其亚型主要为CTX-M-14(64.3%)、CTX-M-15(28.6%)和CTX-M-123(7.1%)。结论本研究发现胃肠外科住院患者体液内存在的大肠杆菌超广谱耐药基因ESBLs主要为CTX-M型,其亚型为CTX-M-14、CTX-M-15和CTX-M-123。

OBJECTIVE Through the detection of drug resistant genotype in Escherichia coli（E.coli）producing extended-spectrumβ-lactamases（ESBLs）from the patients body fluids in Zhejiang Provincial People′s Hospital of the department of gastrointestinal surgery,to explore the indoor epidemic characteristics of drug-resistant genes.METHODS A total of 300 samples of different hospitalized patients＇ body fluids from Aug.2015 to Dec.2015 were collected,and high resistant E.coli strains with ESBLs were screened by VITEK 2Compact automated bacterial identification and antibiotic susceptibility analysis system.Drug resistant genes were detected and extended by PCR technique.The resistant gene isoforms were sequenced and confirmed by BLAST analysis.RESULTS Totally 120 strains of drug-resistant E.coli with ESBLs were screened,the mainly resistant gene was CTX-M in 14 strains of drug-resistant E.coli with ESBLs by PCR,and the mainly resistant gene isoforms were CTX-M-14（64.3%）,CTX-M-5（28.6%）and CTX-M-123（7.1%）.CONCLUSIONThe primary resistant gene was CTX-M and the resistant gene isoforms were CTX-M-14,CTX-M-15 and CTX-M-123 in E.coli with ESBLs from the samples of the hospitalized patients＇ body fluids in the department of gastrointestinal surgery.