亚胺培南耐药鲍曼不动杆菌的碳青霉烯酶基因及同源性分析  

Carbapenemase gene of Imipenem-resistant Acinetobacter baumannii and its homology

作　　者：郭萍[1] 曹彬[1] 尹玉东[1] 刘颖梅[1] 栗方 

机构地区：[1]首都医科大学附属北京朝阳医院北京市呼吸疾病研究所感染和临床微生物科,北京100020

出　　处：《军医进修学院学报》2011年第7期690-694,共5页Academic Journal of Pla Postgraduate Medical School

摘　　要：目的研究本院近3年临床分离的亚胺培南耐药鲍曼不动杆菌耐药现状、同源性及碳青霉烯酶基因型。方法收集2006年1月-2009年7月临床分离存活的、非重复的亚胺培南耐药及敏感对照株鲍曼不动杆菌,进行扩增性rDNA限制性酶切片段分析(ARDRA)分子鉴定菌种,采用琼脂稀释法测定菌株对美罗培南、亚胺培南等抗菌药物的MIC;采用基因间重复序列引物PCR(REP-PCR)和脉冲场凝胶电泳(PFGE)分析同源性;用多重PCR、测序等方法分析鲍曼不动杆菌β-内酰胺酶包括TEM-1型酶、SHV-型酶、GES-型、VEB-型、PER-型及IMP-、VIM-型碳青霉烯酶和OXA型碳青霉烯酶分布特点。结果 274株亚胺培南耐药鲍曼不动杆菌(CRAB)对头孢菌素类、头孢哌酮/舒巴坦、阿米卡星、喹喏酮类抗生素敏感率<10%,对米诺环素敏感率为41.2%;对多黏菌素B 100%敏感。2006年1月-2009年7月期间共检出5个克隆,主要为A1耐药克隆株于不同病房的暴发流行。β-内酰胺酶检测出OXA-23、-66、-69、-72、-58型碳青霉烯酶及PER-1型酶。blaOXA-23-like与blaOXA-51-like基因同时存在的CRAB株为53.6%(147/274)。未检出IMP-、VIM-型碳青霉烯酶及TEM-1型酶、SHV-型酶、GES-型、VEB-型β-内酰胺酶。结论 CRAB克隆株的传播是造成我院碳青霉烯类耐药率增加的重要原因。OXA-51-like、OXA-23型酶为对CRAB对碳青霉烯类耐药的主要碳青霉烯酶。Objective To study the status quo and homology of imipenem-resistant Acinetobacter baumanii and the genomic type of carbapenemase gene isolated from January 2006 to July 2009 in our hospital. Methods A total of 309 living, non-repetitive imipenem-resistant and sensitive Acinetobacter baumanii isolated from January 2006-July 2009 in our hospital were collected to identify their genomic types by amplified rRNA gene restriction analysis（ARDRA）. Minimum inhibitory concentrations （MICs） of meropenem, imipenem and other antibiotics were measured by agar dilution and interpreted according to the clinical laboratory standards Institute （CLSI） breakpoints. The homology of isolates was determined by both pulsed field gel electrophoresis （PFGE） and repetitive extragenic palindromic-polymerasechain reaction （REP-PCR）. blasav, blawB, bla6Es, blaiMP-blavIM-, blaoXA-23-like, blaOXA-24-like, blaOXA-58-1ike, and blaoXA.51-like genes for these strains were amplified and sequenced. Results The CRAB strains resistant rate of cefoperazone/sulbactam, ceftazidime, cefepime, ciprofloxacin and amikacin was less than 10%. The CRAB strain resistant rate of minocycline was 41.2% and the susceptible rate of polymyxin B was 100%. The molecular epidemiology of CRAB typing by PFGE and Rep-PCR showed that 5 different clones were identified. The PFGE pattern A1 was found in 17 different wards, the other clones were named A2, B, C, D and E clones. The multiplex PCR assay amplified fragments of blaoxA alleles encoding each of the 4 subgroups of OXA carbapenemases in Acinetobacter spp. alleles encoding blaoxA-23-like and blaoXA_51_like were detected in 147 of 274（53.6%） isolates. Genes encoding OXA-23, OXA-66, OXA-69, OXA-72, OXA-58 and PER-1 enzymes were detected. Sequence analysis of the products from different wards and MICs for the blaoxA^51-like amplicons （15 cases） identified blaOXA-66 in 14 cases and blaoxA.69 in 2 cases. Conclusion A1 clone spread is the main reason for the increased Imipenem resistance in Chaoyan

关 键 词：鲍曼不动杆菌 碳青霉烯类 耐药 基因同源性 碳青霉烯酶 

分 类 号：R446.5[医药卫生—诊断学]