厄他培南对产超广谱β-内酰胺酶细菌的抑菌活性

In vitro Activity of Ertapenem and Other Antibiotics Against Extended-spectrum Beta-lactamase Producing Escherichia coli and Klebsiella pneumoniae

目的分析厄他培南和常用抗菌药物对产超广谱β-内酰胺酶(ESBLs)菌株的体外抗菌活性。方法采用WalkAway40和NC21板对临床分离的大肠埃希菌、肺炎克雷伯菌鉴定并同时做常用抗菌药物敏感试验,按CLSI推荐的标准方法确认产ESBLs菌株,厄他培南K-B法药敏试验和E-test试验同时进行。结果各病房均分离到产ESBLs菌株,肾内科最高为18.67%,其次依次为脑外科、呼吸科和ICU,分别为11.14%、9.34%和9.04%;产ESBLs菌株以痰液、尿液、分泌物和血液标本为主;产ESBLs菌株对环丙沙星、庆大霉素、妥布霉素和复方新诺明的耐药率分别为63.42%、61.14%、45.22%、61.78%,对阿米卡星和哌拉西林/他唑巴坦耐药率分别为15.29%、11.46%,对亚胺培南100.00%敏感;厄他培南对产ESBLs菌株具有很强的抗菌活性,MIC500.032μg/ml、MIC901.0μg/ml。结论厄他培南对临床分离的产ESBLs大肠埃希菌和肺炎克雷伯菌的抗菌活性较高,较亚胺培南稍弱,有可能成为产卡巴培南酶菌株的筛选抗菌药物。

OBJECTIVE To analyze in vitro activity of ertapenem and other antibiotics against clinical bacterial isolates of ESBLs-producing Escherichia coli and Klebsiella pneumoniae. METHODS E. coli and K. pneumoniae were identified by WalkAway40 with 21CN. ESBLs-producing isolates confirmed accordance with the CLSI guidelines. E-test strips were used for determining the minimum inhibitory concentration （MIC） of ertapenem, while disk diffusion test was performed on each isolate using 10 μg ertapenem disc. RESULTS ESBLs-producing strains were isolated mainly from sputum, urine, secretion and blood, most of them were from nephrology, neurosurgery, Respiratory department and ICU. High resistance rates were shown for both E. coli and K. pneumoniae against cefepime, ciprofloxacin （63.42%）, SMZco （61.78%）, tobramycin （45.22%）and gentamicin （61. 14%）. Most K. pneumoniae and E. coli isolates were susceptible to amikacin （78. 70%） and piperacillin/tazobactam （81. 30%）. Tmipenem showed 100. 00% of activity the isolates. Ertapenem showed activity against 100. 00% ESBLs-producing E. coli, one ESBLs-producing K. pneumoniae isolate showed ertapenem resistance and another one intermediate, the ratio of susceptibility was 99.40%, ertapenem had MIC at which 50.00% and 90.00% of the isolates were inhibited of 0. 032 μg/ml and 1.0 μg /ml for ESBLs-producing organisms respectively. CO.NCLUSIONS Ertapenem is less active to ESBLs-producing organisms then imipenem. Ertapenem resistance appears to be the most sensitive indicator for detection of KPCs.