烧伤患者中产VIM-2型金属β内酰胺酶鲍氏不动杆菌耐药机制及同源性分析  

Analysis of the mechanism of drug resistance of VIM-2-type metallo-β-lactamase-producing Acineto- bacter baumannli isolated from burn patients and its homology

作　　者：杨喜丽[1] 李悦[1] 詹剑华[1] 郭菲[1] 闵定宏[1] 王年云[1] 李国辉[1] 郭光华[1] 

机构地区：[1]南昌大学第一附属医院烧伤中心,330006

出　　处：《中华烧伤杂志》2015年第3期205-210,共6页Chinese Journal of Burns

基　　金：江西省教育厅科学技术研究重点项目（GJJ13200）

摘　　要：目的探讨我院烧伤患者中产VIM-2型金属β内酰胺酶（MBL）的鲍氏不动杆菌（AB）对碳青霉烯类抗生素的耐药机制及同源性。方法2011年9月-2014年3月，收集从笔者单位收治的烧伤住院患者痰液、尿液、血液、脓液、引流液中分离的400株AB（经鉴定）。采用全自动微生物鉴定及药敏分析系统测定菌株对复方磺胺甲嗯唑、氨曲南等15种抗生素的耐药性。针对抗碳青霉烯类抗生素菌株，采用改良Hodge试验筛选产碳青霉烯酶菌株。PCR法及测序检测产碳青霉烯酶AB的碳青霉烯酶基因、携带blaVIM-2基因的产碳青霉烯酶AB的可移动基因元件1类整合子（Intll）及其保守片段（cs）。针对携带blaVIM-2基因产碳青霉烯酶AB行亚胺培南-乙二胺四乙酸（EDTA）协同试验以及亚胺培南．EDTA与头孢他啶-EDTA增效试验验证其产MBL情况，并分析产VIM-2型MBL的AB的耐药情况。对产VIM-2型MBL的AB行质粒接合试验检测质粒转移情况，PCR法检测外膜蛋白CarO基因。十二烷基硫酸钠．聚丙烯酰胺凝胶电泳检测携带CarO基因的产VIM-2型MBL的AB菌株的CarO蛋白表达量。肠杆菌基因间重复一致序列（ERIC）-PCR法对产VIM-2型MBL的AB菌株进行基因分型，分析同源性。结果（1）400株AB对左氧氟沙星和复方磺胺甲嘿唑的耐药率低。共筛选出381株抗碳青霉烯类抗生素AB，其中240株产碳青霉烯酶。（2）240株产碳青霉烯酶AB中检出18株携带VIM-2酶基因6laVIM-2，占7．5％；133株携带bla TEM-1基因，占55．42％；195株携带blaOXA-23基因，占81．25％；188株携带bla armA基因，占78．33％。（3）18株携带blaVIM-2基因的产碳青霉烯酶AB均携带Intll基因，呈现Intll．VIM连锁携带型，Infll可变区Cs呈现多样性。（4）经验证，18株携带blaVIM-2基因的产碳青霉烯酶AB均为产VIM-2型MBL的AB。该18株AB菌株对复方磺胺甲嘿唑的耐药率最低，其次为左氧氟沙星和头�Objective To study the drug resistance ofAcinetobacter baumannii （AB） producing VIM-2-type metallo-β-1actamase （MBL） isolated from burn patients of our ward against carbapenem antibiot- ics and its homology. Methods A total of 400 strains of AB （identified） were isolated from sputum, u- rine, blood, pus, and wound drainage of burn patients hospitalized in our ward from September 2011 to March 2014. Drug resistance of the 400 strains of AB to 15 antibiotics, including compound sulfamothox- azole, aztreonam, etc. , was tested using the automatic microorganism identifying and drug sensitivity analy- zer. Among the carbapenems-resistant AB isolates, modified Hodge test was applied to screen carbapene- mase-producing strains. The carbapenemase genes of the carbapenemase-producing strains, and the mobile genetic elements class 1 integron （ Intll ） gene and conserved sequence （CS） of carbapenemase-producing strains carrying bla WM-2 gene were determined with PCR and DNA sequencing. For carbapenemase-producing strains carrying bla VIM-2 gene, synergism test with imipenem-ethylene diamine tetraacetic acid （EDTA） and enhancement test with imipenem-EDTA and ceftazidime-EDTA were used to verify the MBL-producing sta- tus. Drug resistance of the VIM-2-type MBL-producing AB strains was analyzed. For VIM-2-type MBL-pro- ducing AB strains, plasmid conjugation experiment was used to explore the transfer of plasmid; outer mem- brane protein （OMP） CarO gene was detected by PCR. For VIM-2-type MBL-producing AB strains carrying CarO gene, the protein content of CarO was analyzed with sodium dodecyl sulfate polyacrylamide gel electro- phoresis. The repetitive consensus sequence of Enterobacteriaceae genome PCR （ERIC-PCB） was carried out for gene typing of VIM-2-type MBL-producing AB strains to analyze their homology. Results （ 1 ） The resistant rates of the 400 strains of AB against levofloxacin and compound sulfamethoxazole were low. A total of 381 carbapenems-resistant AB strains were screened, i

关 键 词：烧伤 感染 鲍氏不动杆菌 抗药性 Β内酰胺酶类 细菌外膜蛋白质类 碳青霉烯酶 

分 类 号：R446.5[医药卫生—诊断学] R644[医药卫生—临床医学]