腹腔感染大肠埃希菌和肺炎克雷伯菌的耐药性监测

目的监测2008—2010年我国不同地区6所教学医院腹腔感染患者中分离的大肠埃希菌和肺炎克雷伯菌的体外药物敏感性。方法收集2008—2010年全国6所教学医院腹腔感染患者分离的大肠埃希菌和肺炎克雷伯菌。采用微量肉汤稀释法测定多种抗菌药物的最低抑菌浓度(MIC)。数据采用WHONET 5.6软件进行耐药性分析。结果 2008—2010年共收集到腹腔感染大肠埃希菌789株和肺炎克雷伯菌263株。对于大肠埃希菌,碳青霉烯类抗生素物具有高度体外抗菌活性(细菌对其敏感率96.7%～99.3%),哌拉西林-他唑巴坦(87.1%～93.2%)和阿米卡星(86.7%～89.8%)次之。细菌对头孢他啶的敏感率较高(48.5%～59.2%),2010年头孢曲松、头孢噻肟和头孢吡肟的敏感率仅为24.5%～32.8%。细菌对2种氟喹诺酮类药物的敏感率逐年降低,对氨苄西林-舒巴坦的敏感率最低,为12.4%～20.6%。大肠埃希菌中ESBLs的检出率逐年上升,从2008年的59.7%升至2010年的73.5%。厄他培南(90.4%～94.1%)、亚胺培南(95.1%～97.1%)、阿米卡星(79.2%～92.6%)和哌拉西林-他唑巴坦(80.2%～85.3%)对肺炎克雷伯菌保持了较高的抗菌活性。细菌对头孢他啶(66.3%～72.1%)和头孢吡肟(67.3%～79.1%)的敏感率略高于头孢噻肟(59.4%～61.8%)和头孢曲松(60.3%～60.6%)。细菌对2种氟喹诺酮类药物的敏感率从2008年的58.4%～60.4%到2010年的64.7%～72.1%。肺炎克雷伯菌中产ESBLs菌株的检出率略有下降,从2008年的37.6%至2010年的28.1%。产ESBLs菌株对厄他培南和亚胺培南保持了高的敏感率(88.5%～99.4%)。结论腹腔感染患者中分离的大肠埃希菌和肺炎克雷伯菌对碳青霉烯类抗生素、哌拉西林-他唑巴坦和阿米卡星保持了较高的体外敏感性。大肠埃希菌对第三代、第四代头孢菌素和氟喹诺酮类抗菌药物敏感性较低,提示临床上应谨慎使用。

Multicenter antimicrobial resistance surveillance in the strains of Escherichia coli and Klebsiella pneumonia isolated from intra-abdominal infections in China

Objective To investigate the antimicrobial resistance in the strains of E.coli and K.pneumoniae isolated from intra -abdominal infections in 6 teaching hospitals located at different geographical region of China during 2008-2010.Methods The E.coli and K.pneumoniae strains isolated from intra-abdominal infections in 6 teaching hospitals were collected and sent to the central lab for re-identification and susceptibility testing. The minimum inhibitory concentrations(MICs) of antimicrobial agents were determined by broth microdilution method.WHONET 5.6 software was used to analyze the data.Results A total of 789 strains of E.coli and 263 K.pneumoniae were collected during 2008-2010.Carbapenems remained the most active agent against E.coli(96.7%-99.3%susceptible),followed by piperacillintazobactam (87.1%-93.2%) and amikacin(86.7%-89.8%). Ceftazidime showed higher activity(48.5%-59.2%susceptible) than ceftriaxone,cefotaxime and cefepime(24.5%-32.8%susceptible). The susceptibility of these strains to fluoroquinolones was decreasing year by year.Ampicillin-sulbactam showed the lowest activity(12.4%-20.6%susceptible).The prevalence of ESBL-producing strains ranged from 59.7%in 2008 to 73.5%in 2010.As for K.pneumoniae,ertapenem(00.4%-94.1% susceptible),imipenem(95.1%-97.1%).amikacin(79.2%-92.6%) and piperacillin-tazobaciam(80.2%-85.3%) showed relatively higher activity.The susceptibility rate to ceftazidime(66.3%-72.1%) and cefepime(67.3%-79.1%) were higher than cefotaxime(59.4%-61.8%) and ceftriaxone(60.3%-60.6%).The susceptibility to fluoroquinolones increased from 58.4%-60.4%in 2008 to 64.7%-72.1%in 2010.The prevalence of ESBL-producing strains decreased from 37.6%in 2008 to 28.1%in 2010.ESBL-producing isolates remained highly susceptible to ertapenem and imipenem(88.5%-99.4%).Conclusions Carbapenems,amikacin and piperacillin-tazobactam are highly active against the E.call and K.pneumoniae isolated from intra-abdominal infections,while the third/fourth generation cephalosporins and fluoroquinolones showed poor activity against E.coli ? to which clinicians should pay attention.