目的研究克雷伯菌属对亚胺培南耐药机制以及KPC-2基因在克雷伯菌属中传播机制。方法收集四川大学华西医院两个阶段(2009~2010年和2012~2013年)分离的对亚胺培南耐药的克雷伯菌属细菌。琼脂稀释法测定亚胺培南最低抑菌浓度(MIC),CARB ChromID平板和改良Hodges试验检测碳青霉烯耐药表型,PCR检测细菌的KPC-2基因表达。质粒接合试验检测质粒传播性。随机引物扩增多态性DNA(RAPD)方法和肠杆菌基因间重复一致序列聚合酶链反应(ERIC-PCR)技术分别用于分析质粒和菌株的同源性。结果第一阶段筛选并确证耐亚胺培南的3株产酸克雷伯菌首先获得碳青酶烯类抗生素耐药性,第二阶段筛选并确证耐亚胺培南的7株肺炎克雷伯菌出现相同的获得性耐药。PCR显示10株细菌均携带KPC-2型基因。质粒接合试验显示产酸克雷伯菌中携带KPC-2基因的质粒可以传递到受体菌,且与KPC-2基因阳性的肺炎克雷伯菌中携带的质粒具有同源性。ERIC-PCR结果显示7株KPC-2基因阳性的肺炎克雷伯菌具有同源性。结论四川大学华西医院分离的对亚胺培南耐药的肺炎克雷伯菌和产酸克雷伯菌主要耐药机制是产生KPC-2型碳青霉烯酶。产酸克雷伯菌中携带KPC-2基因质粒,该质粒具有传递性且与肺炎克雷伯菌携带质粒相同。肺炎克雷伯菌中耐药株的传播形式为同一克隆传播,而在克雷伯菌属中不同菌种间耐药传播途径为同一质粒的水平传播。 Objective To study the resistance mechanism of Klebsiella to imipenem and the mechanism of KPC-2 gene transmission in Klebsiella. Methods Klebsiella bacteria resistant to imipenem were isolated in two stages (2009-2010 and 2012-2013) of West China Hospital of Sichuan University. The minimum inhibitory concentration (MIC) of imipenem was determined by agar dilution method. The resistant phenotype of carbapenems was detected by CARB ChromID plate and modified Hodges test. The KPC-2 gene expression was detected by PCR. Plasmid splicing assay detects plasmid transmissibility. Random amplified polymorphic DNA (RAPD) method and Enterobacterial repetitive consensus polymerase chain reaction (ERIC-PCR) were used to analyze the homology of the plasmid and the strain, respectively. Results The first phase screening and confirmation of imipenem 3 strains of Klebsiella oxytoca first obtained carbapenem antibiotic resistance, the second phase of screening and confirmed imipenem-resistant 7 Klebsiella pneumoniae The same acquired acquired resistance. PCR showed that all 10 strains carried KPC-2 gene. Plasmid conjugation assays showed that plasmids carrying the KPC-2 gene in Klebsiella oxytoca can be transmitted to recipient bacteria and have homology to the plasmid carried in KPC-2-positive Klebsiella pneumoniae. ERIC-PCR results showed that seven strains of KPC-2-positive Klebsiella pneumoniae shared homology. Conclusions The main mechanism of resistance to imipenem-resistant Klebsiella and Klebsiella producing bacteria isolated in West China Hospital of Sichuan University is the generation of carbapenemase KPC-2. Klebsiella oxytoca carries the KPC-2 gene plasmid, which is transitive and identical to the Klebsiella pneumoniae-carrying plasmid. Klebsiella pneumoniae resistant strains in the form of transmission of the same clone, and in Klebsiella strains of different drug-resistant transmission routes for the same plasmid level.