烧伤病区产超广谱β-内酰胺酶革兰阴性菌分离率及耐药性分析

A survey of the prevalence and antimicrobial susceptibility of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in Burn Unit

目的 了解我院特别是烧伤病区产超广谱β -内酰胺酶 (ESBLs)大肠杆菌、肺炎克雷伯杆菌的流行情况 ,检测其对常用抗生素的耐药性 ,为临床治疗和控制ESBLs菌感染及流行提供重要依据。方法 通过中心化验室收集我院 2 0 0 0年 3月～ 2 0 0 1年 2月住院患者送检标本中大肠杆菌、肺炎克雷伯杆菌共计 2 5 8株 ,应用VITEK自动检测系统 (GNS - 5 0 6药敏分析卡 )及双纸片扩散法筛选产ESBLs菌。根据VITEK自动检测系统药敏检测结果分析比较产ESBLs菌和非产ESBLs菌对 15种抗生素的敏感性 ,并对其中 38株产ESBLs阳性菌进行 12种临床常用抗生素MIC检测。结果 2 5 8株入选菌株中产ESBLs阳性率分别为 :大肠杆菌 18 8% ( 2 9/ 15 4 ) ;肺炎克雷伯杆菌 12 5 % ( 13/10 4 )。按标本种类分析 ,分泌物标本培养产ESBLs阳性率最高 ,为 2 5 5 % ,与其他标本培养的总阳性率间的差别有显著性意义 ;按病区分析 ,烧伤病区产ESBLs阳性率 (大肠杆菌 38 5 % ;肺炎克雷伯杆菌 2 5 0 % )与其他病区产ESBLs阳性率间差别有显著性意义。药敏结果 :产ESBLs的大肠杆菌和肺炎克雷伯杆菌对亚胺培南、美洛培南及头孢西丁的敏感率较高 ,其次是氨基糖苷类抗生素 ,产ESBLs的肺炎克雷伯杆菌对哌拉西林 /三唑巴坦敏感 。

Objective To determine epidemic features of extended-spectrum beta-lactamase(ESBL)-producing Escherichia coli(E coli) or Klebsiella pneumoniae(K pneumoniae) in burn unit.Methods 258 non-duplicated strains of E coli and K pneumoniae were collected from different wards in hospital during Mar.2000 to Feb.2001.Producing ESBLs strains were detected by using GNS-506 susceptibility card of Vitek-60 system and double-disk synergy test. The antimicrobial susceptibility of all the strains was detected by Vitek system.Results 42 strains producing ESBLs were found in 258 strains.Of these,18 8% of E coli,12 5% of K pneumoniae were the ESBLs producing strain.The isolated rate of ESBLs in burn unit(E coli 38 5%;K pneumoniae 25 0%) was higher than that in other wards.The antimicrobial susceptibility of isolated strains producing ESBLs was lower than that of non-producing ESBLs strains.Imipenem,meropenem and cefoxitin were the most active antibiotics against ESBLs-producing E coli and K pneumoniae,while amikacin and netilmicin also showed higher activity.Conclusion Burn unit is one of the highest epidemic wards of ESBLs-producing E coli or K pneumoniae.Imipenem,meropenem,cefoxitin could be a better choice to control the burn infection due to ESBLs-producing organisms.