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.
出处
《中国感染与化疗杂志》
CAS
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)。