产超广谱β内酰胺酶大肠埃希菌的耐药性及基因型研究  

Antimicrobial resistance and genotypes of extended-spectrum β-lactamases in Escherichia coli

作　　者：周东升[1] 潘晓龙[1] 熊自忠[2] 吴祥林[1] 吴志平[1] 富铮[1] 蒋静 

机构地区：[1]安徽铜陵市人民医院检验科,安徽铜陵244000 [2]安徽医科大学附属医院感染科 [3]安徽铜陵市中医院检验科

出　　处：《中国感染与化疗杂志》2006年第5期317-320,共4页Chinese Journal of Infection and Chemotherapy

基　　金：安徽省自然科学基金(050430804)。

摘　　要：目的了解我院临床分离的大肠埃希菌中产ESBLs菌株的阳性率、耐药性及ESBLs基因型。方法采用纸片扩散法(K-B法)测定2004年1月-2005年12月我院临床分离221株大肠埃希菌对23种抗菌药物的敏感度,用酶抑制剂增强试验(纸片法)进行产ESBLs菌株的检测;用PCR和DNA序列分析检测ESBLs基因型。并用WHONET5．3软件进行统计分析。结果221株大肠埃希菌中共检出89株产ESBLs菌株(40．3％);产ESBLs菌株对青霉素类、第一、第二代头孢菌素100％耐药,第三代头孢菌素中,除细菌对头孢他啶耐药率为41．6％外,对头孢哌酮、头孢噻肟、头孢曲松的耐药率均在95％以上．对哌拉西林-三唑巴坦、头孢哌酮-舒巴坦的耐药率分别为9．0％、18．0％;对亚胺培南的耐药率为0％;89株产ESBLs菌株中,88株(98．9％)PCR检测ESBLs基因型阳性,且均为CTX—M型,其中CTX-M-14为86．5％(77／89)、CTX-M-3为19．1％(17／89),6株细菌(6．7％)同时产CTX-M-14和CTX-M-3。结论我院大肠埃希菌中产ESBLs菌株阳性率较高;产ESBLs菌株耐药显著,ESBLs基因型以CTX-M-14型为主。未检出其他型ESBLs。Objective To investigate the prevalence, resistance and genotypes of extended-spectrum β-lactamases in E. coli isolates. Methods K-B disk diffusion method was used in susceptibility testing and ESBLs producers were detected by NCCLS Phenotypie Confirmatory Test （disk diffusion test） in E. coli isolates. The β-laetamase genes were identified by PCR and sequencing. Results The prevalence of ESBLs producers were 40.3% and all of them were resistant to penicillins, the first, second generation cephalosporins. The resistance rates to ceftriaxone, cefotaxime, and cefoperazone were more than 95%, but only 41.6H to ceftazidime. The resistance rates to piperacillin-tazobactam, cefoperazone-sulbactam, gentamicin, trimethoprim- sulfamethoxazole, fluoroquinolones, and imipenem were 9.0%, 18.0%, 62.9%, 83.1%, 75.3% and 0 %. ESBLs gene was positive in 98.9% （88/89） of the E. coli strains by PCR. CTX-M-14 was the most prevalent （86. 5%, 77/89） genotype. Some ESBLs producers produced more than one type of ESBLs. Conclusions ESBLs producers are common in E. coli isolated from our hospital. Most of them are multidrug resistant. CTX-M-14 was the main genotype of ESBLs. Other genotype of ESBLs is not found.

关 键 词：大肠埃希菌 超广谱Β内酰胺酶 基因型 耐药性 

分 类 号：R378[医药卫生—病原生物学]