革兰阴性杆菌对亚胺培南耐药性的变迁

目的 调查近3年医院革兰阴性杆菌对亚胺培南的耐药率.方法 收集2008年7月-2010年12月住院及门诊患者各种标本中分离的革兰阴性杆菌,使用MicroScan-WalkWay40全自动微生物分析仪进行菌种鉴定及药敏试验,对结果进行回顾性分析.结果 3年来分离到的革兰阴性杆菌排前5位的依次为铜绿假单胞菌、肺炎克雷伯菌、鲍氏不动杆菌、大肠埃希菌和阴沟肠杆菌,共分离出革兰阴性杆菌4083株,肠杆菌科细菌2104株占51.5％,非发酵菌1880株占46.0％,其他99株占2.5％；3年来肠杆菌科细菌对亚胺培南耐药率,阴沟肠杆菌为9.5％、5.4％、8.3％,肺炎克雷伯菌为4.2％、8.8％、6.2％,大肠埃希菌为0、0.6％、1.3％；非发酵菌中(嗜麦芽寡养单胞菌除外)鲍氏不动杆菌为58.0％、48.5％、68.8％,铜绿假单胞菌为23.1％、15.3％、11.9％,鲁氏不动杆菌为23.8％、5.9％、3.6％.结论 临床分离的革兰阴性杆菌主要为肠杆菌科细菌和非发酵菌；肠杆菌科细菌以肺炎克雷伯菌、大肠埃希菌和阴沟肠杆菌为主,非发酵菌以铜绿假单胞菌和鲍氏不动杆菌为主；肺炎克雷伯菌对亚胺培南耐药率较高,大肠埃希菌对亚胺培南耐药率呈上升趋势,应引起重视；鲍氏不动杆菌等非发酵菌对亚胺培 南的体外抗菌活性较差,但耐药率有下降趋势.

Changes of resistance to imipenem in gram-negative bacilli

OBJECTIVE To investigate the resistance rate of gram-negative bacilli to imipenem.METHODS Gram-negative bacilli isolated from various specimens of the inpatients and outpatients in hospital from Jul.2008 to Dec.2010 were collected.The identification and antimicrobial susceptibility test were performed by MicroScan-WalkWay40 automated microbiology analyzer and the results were retrospectively analyzed.RESULTS The top 5 gram-negative bacilli isolated during the past 3 years were in turn as follows:in turn as follows:Pseudomonas aeruginosa,Klebsiella pneumoniae,Acinetobacter baumannii,Escherichia coli and Enterobacter cloacae.A total of 4083 strains of gram-negative bacilli were isolated,including 2104 isolates of Enterobacteriaceae(51.5%),1880 isolates of nonfermenting bacteria(46.0%) and 99 isolates of others(2.5%).The resistance rates of Enterobacteriaceae to imipenem during the past 3 years were as follows:E.cloacae(9.5%,5.4%,8.3%),Klebsiella pneumoniae(4.2%,8.8%,6.2%),and E.col i(0,0.6%,1.3%);the resistance rates of nonfermenting bacteria(excluding Stenotrophomonas maltophilia) to imipenem were as follows:A.baumannii(58.0%,48.5%,68.8%),P.aeruginosa(23.1%,15.3%,11.9%) and Lafite Acinetobacter(23.8%,5.9%,3.6%).CONCLUSION The gram-negative bacilli isolated are mainly Enterobacteriaceae and nonfermenting bacteria;the predominant Enterobacteriaceae are K.pneumoniae,E.coli and E.cloacae,and the predominant nonfermenting bacteria are P.aeruginosa and A.baumannii.The resistance rate of K.pneumoniae to imipenem is high,the resistance rate of E.coli to imipenem keeps an upward trend,which deserves our attention.Nonfermenting bacteria like A.baumannii are with poor in vitro antibacterial activity against imipenem,but the resistance rate tends to decrease.