目的 研究北京大学第一医院呼吸监护室近年来的鲍曼不动杆菌的耐药情况，亚胺培南耐药鲍曼不动杆菌的分子流行病学及其碳青霉烯酶的基因型。 方法 选取我院呼吸监护室2006年1月-2008年7月以及2009年1-4月间迁入新呼吸监护室后分离到的鲍曼不动杆菌。此外还选取了与后者同期的2株急诊室分离到的耐亚胺培南的鲍曼不动杆菌。对其患者的临床资料进行分析，采用琼脂二倍稀释法测定13种抗菌药物对亚胺培南耐药菌株的最低抑菌浓度(MIC)，采用脉冲场凝胶电泳法(PFGE)对耐药菌株进行同源性分析，采用PCR法检测亚胺培南耐药鲍曼不动杆菌碳青霉烯酶基因型。 结果 2006年1月-2008年7月呼吸监护室共分离到57株鲍曼不动杆菌，其中50株对亚胺培南敏感，7株对亚胺培南耐药；2009年1-4月共分离到5株鲍曼不动杆菌，100%对亚胺培南耐药。亚胺培南耐药与敏感鲍曼不动杆菌感染患者有糖尿病史的比率分别为58.33%和18.00%(P=0.04)；亚胺培南耐药鲍曼不动杆菌和亚胺培南敏感鲍曼不动杆菌感染患者病死率分别为60%和28.26%。所有亚胺培南耐药鲍曼不动杆菌对美洛培南耐药，对米诺环素均敏感。12株亚胺培南耐药鲍曼不动杆菌根据PFGE条带分析发现属于6个克隆株，其中9株菌属于A、D、E3个克隆，为主要流行克隆株，E克隆仅出现在2009年分离到的菌株中，同期急诊室的两株亚胺培南耐药鲍曼不动杆菌同属E克隆。PCR检测显示，12株菌OXA-23组、OXA-51组酶基因均阳性。未检测到OXA-24组、 OXA58组、IMP型和VIM型碳青霉烯酶基因。 结论 北大医院呼吸监护室患者糖尿病史与亚胺培南耐药鲍曼不动杆菌感染发生有关。对亚胺培南耐药的鲍曼不动杆菌全部对美洛培南耐药。我院呼吸监护室亚胺培南耐药鲍曼不动杆菌的流行与院内感染，包括从急诊室输入相关。其碳青霉烯酶基因型为OXA-23组和OXA-51组。 关键词：鲍曼不动杆菌，耐药性，脉冲场凝胶电泳(PFGE)，碳青霉烯酶

 Objectives: To investigate the resistance of Acinetobacter baumannii , molecular epidemiology, carbapenemase genes of imipenem-resistant Acinetobacter baumannii in RICU of Peking University First Hospital in recent years. Methods: Isolates of A. baumannii were recovered from RICU of our hospital, form January 2006 to July 2008 and also from January to April of 2009 after RICU was moved to a new building. The risk factors, clinical courses, mortality of these patients were investigated. The MICs of 13 antimicrobials to resistant isolates were detected by agar dilution and PFGE was performed to analyse their relatedness. Two isolates from emergency department during the same period were also tested. The genotypes of carbapenamases were determined by PCR and DNA sequencing. Results: Form January 2006 to July 2008, 57 isolates of A. baumannii were recovered from RICU, 50 isolates were sensitive to imipenem, and 7 isolates were resistant to imipenem, as well as another 5 isolates of A. baumannii, which were all imipenem-resistant between January to April of 2009 after RICU moving. Imipenem-resistant and imipenem-sensitive A. baumannii infected patients with diabetes mellitus are 58.33% and 18.00% (P=0.04). Mortality of imipenem-resistant and imipenem-sensitive A. baumannii infected patients are 60.00% and 28.26%. All imipenem-resistant isolates were also resistant to meropenem, but susceptible to minocycline. PFGE revealed 6 patterns in 12 strains of imipenem-resistant A. baumannii, in which clones A, D, and E involving 9 isolates were dominant. Clone E was present in strains recovered from RICU in 2009 and from emergency room during the same period. PCR confirmed the presence of bla-OXA-23-like and bla-OXA-51-like genes in all imipenem-resistant isolates, with no bla-OXA-24-like, bla-OXA-58-like, IMP-type, or VIM-type genes detected. Conclusions: Diabetes mellitus might be associated with imipenem-resistant A. baumannii infection in our RICU. There is clonal spread of imipenem-resistant A. baumannii inside RICU, including the influx from emergency room. Carbapenemase genotypes are bla-OXA-23-like and bla-OXA-51-like. Keywords: Acinetobacter baumannii; resistance; pulse field gel electrophresis (PFGE); carbapenem