医源性尿路感染大肠埃希菌与奇异变形菌的耐药性分析

Analysis of drug resistance of Escherichia coli and Proteus mirabilis in iatrogenic urinary tract infections

目的探讨医源性大肠埃希菌及奇异变形菌引起尿路感染的相关性与耐药机制,并分析大肠埃希菌及奇异变形菌产超广谱β-内酰胺酶(ESBLs)的情况,为指导临床合理使用抗菌药物提供参考依据。方法回顾性分析2012年1月-2013年12月临床送检的尿液标本分离出大肠埃希菌及奇异变形菌进行鉴定和药物敏感性试验,并作ESBLs初筛和确证试验,采用WHONET 5.6软件进行统分析。结果共分离出病原菌1 181株,大肠埃希菌893株占75.61%,奇异变形菌288株占24.39%;大肠埃希菌对头孢他啶、头孢唑林、头孢噻肟、头孢曲松和氨曲南的耐药率较高,均>85.00%,而对亚胺培南、美罗培南的耐药率较低,均<2.00%;奇异变形菌对庆大霉素、呋喃妥因、磺胺甲噁唑/甲氧苄啶的耐药率较高,均>66.00%。结论大肠埃希菌及奇异变形菌是引起医源性尿路感染的主要病原菌;大肠埃希菌及奇异变形菌产ESBLs菌株检出率较高,产ESBLs菌对头孢菌素类、喹诺酮类、磺胺类和氨基糖苷类等抗菌药物呈多药耐药性。

OBJECTIVE To investigate the correlation and drug resistance mechanism of Escherichia coli and Proteus mirabilis causing iatrogenic urinary tract infections and. the produution of extended-spectrum β-lactamases （ESBLs） in E. coli and P. mirabilis so as to provide evidence to guide the clinical reasonable use of antibiotics. METHODS A total of 197 strains of E. coli and P. rnirabilis isolated from the urine specimens of hospitalized patients from Jan. 2012 and Dec. 2013 were retrospectively analyzed as well as drug susceptibility, and screening and confirmatory tests were done to identify ESBLs-producing strains. The software WHONET 5.6 was used for statistical analysis. RESULTS Totally 1181 strains of pathogens were isolated, including 893 strains of E. coli accounting for 75.61% and 288 strains of P. mirabilis accounting for 24.39%. The drug resistance rate of E. coli was over 85.38% to ceftazidime, cefazolin, cefotaxime, ceftriaxone and aztreonam, and the drug resistance rate of it was lower than 〈2. 00% to Imipenem and Meropenem. The drug resistance rate of P. mirabilis was over 66.00% to gentamicin, nitrofurantoin and sulfamethoxazole/trimethoprim. CONCLUSION E. coli and P. mirabi lis were main pathogens in iatrogenic urinary tract infections. The prevalence of ESBLs is high in E. coli and P. mirabilis isolates. ESBLs-producing strains are resistant to multi-antibiotics, including penicillins, cepbalosporins, quinolones, sulfonamides and aminoglycosides.