ESBLs肠道致病菌中CTX-M基因的鉴定与分型  

Identification of ESBLs producing enteropathogenic bacteria and genotyping of CTX-M

作　　者：党荣理[1] 董路宁[1] 刘栓奎[1] 李明[1] 刘磊[1] 何俊伟[1] 吴静怡[1] 刘正祥[2] 孙立茹 蒋莹[4] 

机构地区：[1]新疆军区疾病预防控制中心,乌鲁木齐830011 [2]兰州军区乌鲁木齐总医院,乌鲁木齐830001 [3]解放军第四七四医院二十三临床部,乌鲁木齐830000 [4]新疆医科大学第二附属医院,乌鲁木齐830028

出　　处：《中国抗生素杂志》2013年第4期293-296,313,共5页Chinese Journal of Antibiotics

基　　金：国家科技重大专项(项目编号:2009ZX10004-205)

摘　　要：目的了解临床分离肠道致病菌中产ESBLs菌株的发生率、流行特征及产CTX-M型耐药表型和基因型。方法对临床分离到的161株肠道致病菌进行ESBLs表型确证试验;采用聚合酶链反应(PCR)检测CTX-M基因,对PCR产物测序并确定基因亚型;采用K-B琼脂扩散法对23种抗菌药物的耐药性进行检测。结果 161株肠道致病菌中有85株(52.8%)ESBLs表型检测阳性。PCR扩增结果表明,共有24株(28.2%)携带CTX-M型基因,其中10株(41.7%)检出CTX-M-1组基因,14株(58.3%)检出CTX-M-9组基因。基因测序确定存在CTX-M-3、CTX-M-14、CTX-M-15、CTX-M-24、CTX-M-27等多种亚型,以CTX-M-14为主。药敏结果显示,不同基因型均对青霉素类,第一、二、三代头孢菌素类抗生素有较为明显的抗药性。结论乌鲁木齐地区肠道致病菌产ESBLs现象较为普遍,对氨苄西林、头孢唑林、头孢噻吩、和头孢呋辛高度耐药。细菌基因型以CTX-M-14亚型为主,同时存在多种亚型。首次在新疆地区检出CTX-M-3、CTX-M-15、CTX-M-24、CTX-M-27基因亚型。Objective To identify the distribution of ESBLs in enteropathogenic bacteria and its epidemiological characteristics in clinical data, and to find out the genotype of CTX-M and its resistance phenotype. Methods 161 clinical strains of multi-resistant Enterobacteriaceae isolates were collected, ESBLs-producing isolates were confirmed by phenotypic confirmatory tests： PCR and DNA sequencing were used to determine the genotype of the CTX-M; K-B agar diffusion test was employed to detect the drug resistance of 23 antibacterial agents. Results 85 of 161 enteropathogenic bacteria were positive for phenotype of ESBLs. 24 of 85 ESBLs isolates were confirmed to carry CTX-M encoding genes, including 10 strains （41.7%） producing CTX-M-1, 14 strains （58.3%） CTX-M-9. CTX-M-3, CTX-M-14, CTX -M-15, CTX-M-24, CTX-M-27 were also found. Antimicrobial susceptibility test＇s results showed that drug sensitivity of different genotypes were different, but they all resisted to cephalosporin of the first, the second and the third generation. Conclusion ESBLs were widespread in Urumqi area, and they showed a high resistance to ampicillin, cefazolin, cefoxitin and cefuroxime. Subtypes of CTX-M-14 were principal and coexisted with CTX-M-3, CTX-M- 15, CTX-M-24 and CTX-M-27 in XinJiang which was never reported before.

关 键 词：乌鲁木齐 肠道致病菌 超广谱Β-内酰胺酶 CTX-M基因 耐药性 

分 类 号：R378[医药卫生—病原生物学]