碳青霉烯类耐药鲍曼不动杆菌分子流行病学及耐药.doc

碳青霉烯类耐药鲍曼不动杆菌分子流行病学及耐药机制的研究 张晓兵，刘 星，龚雅利，府伟灵 （400038 重庆，第三军医大学西南医院检验科） [摘要] 目的 分析我院碳青霉烯类耐药鲍曼不动杆菌分子流行病学及耐药机制。方法 鲍曼不动杆菌源自2008年1—12月我院临床分离株，共51株。采用K-B法（CLSI 2008年标准）筛选对碳青霉烯类耐药的鲍曼不动杆菌临床分离株，采用随机引物多态性DNA(RAPD)分型对其进行分子流行病学研究；PCR方法检测TEM、SHV、CTX-M、IMP-1、IMP-2、VIM、VIM-2、OXA-23、OXA-24等耐药基因型以及Ⅰ、Ⅱ类整合酶。结果 51株碳青霉烯类耐药鲍曼不动杆菌为多重耐药菌株，除阿米卡星外，其他抗生素耐药率非常高；其中50株为同一克隆株；TEM、SHV、CTX-M、IMP-1、VIM-2、OXA-23、Int1基因阳性率分别为98.0%、23.5%、19.6%、25.5%、19.6%、72.5%、86.3%；而IMP-2、VIM、OXA-24和Int-2基因均为阴性。结论 我院碳氢霉烯类耐药鲍曼不动杆菌暴发，携带TEM型β-内酰胺酶、OXA-23、IMP-1和VIM-2型碳青霉烯酶基因和Ⅰ类整合酶。产生OXA-23型碳青霉烯酶和金属酶是本院鲍曼不动杆菌对碳氢霉烯类耐药的主要机制。 [关键词] 鲍曼不动杆菌；碳青霉烯类；耐药性 [中图法分类号] [文献标志码] A Molecular epidemiology and resistant mechanisms of carbapenem-resistant Acinetobacter baumannii Zhang Xiaobing,Liu Xing,Gong Yali, Fu Weiling (Department of Laboratory Medicine,Southwest Hospital,Third Military Medical University,Chongqing, 400038,China) [Abstract] Objective To investigate molecular epidemiology and resistance mechanism of carbapenem-resistant Acinetobacter baumannii（CRAB）.Methods Antimicrobial susceptibility test was done on 51 strains of Acinetobacter baumannii isolated by Kirby-Bauer method. Results were assessed according to the standands recommended by CLSI (2008). The homology of 51 isolates of CRAB was determined by randomly amplified polymorphism DNA (RAPD).The genotype of TEM, SHV, CTX-M, IMP-1, IMP-2, VIM, VIM-2, OXA-23, OXA-24 and class Ⅰ,Ⅱ integrase was performed by polymerase chain reaction (PCR). Results 51 strains Acinetobacter baumannii were multi-drug resistant. Sensitive to antibiotics except Amikacin were low. 50 strains were the same clone . Positive rate of strains of TEM,SHV,CTX-M,IMP-1,VIM-2,OXA-23,Int1 was 98.0%, 23.5%, 19.6%, 25.5%, 19.6%, 72.5%, 86.3%, respectively. But no IMP-2,VIM,OXA-24 and Int-2 type gene was detected. Conclusion Carbapenem-resistant Acinetobacter baumannii broke out which carried TEM, OXA-23, IMP-1,VIM-2 and Int-2 type gene. Production of OXA-23 carbapenemase and metall