铜绿假单胞菌耐药性及质粒介导的耐环丙沙星分子机制研究  

Study on drug resistance and plasmid-mediated resistance mechanisms of ciprofloxacin-resistant Pseudomonas aeruginosa

作　　者：陈茶[1] 黄彬[2] 陈利达[2] 吴强贵[3] 陈树林[2] 李有强[1] 林冬玲[1] 张妮[1] 

机构地区：[1]广东省中医院检验医学部,广东广州510120 [2]中山大学附属第一医院检验医学部,广东广州510080 [3]广州医学院医学检验系,广东广州510000

出　　处：《中华医院感染学杂志》2012年第16期3444-3447,共4页Chinese Journal of Nosocomiology

基　　金：国家自然科学基金资助项目(30770935);广东省科技计划项目(2011B031800037);广东省医学科研基金资助项目(A2011168)

摘　　要：目的研究临床分离铜绿假单胞菌的耐药性和质粒介导铜绿假单胞菌对环丙沙星耐药的分子机制。方法采用VITEK-2型全自动微生物检测系统鉴定细菌,用K-B法测定铜绿假单胞菌对24种常用抗菌药物的药敏率,用聚合酶链反应检测喹诺酮类耐药基因,包括qnrA、qnrB、qnrC、qnrD、qnrS、qepA和aac(6′)-Ib-cr。结果 423株铜绿假单胞菌对环丙沙星和左氧氟沙星的耐药率均为23.2%,对第一、三代头孢菌素类药物的耐药率>49.2%(除头孢他啶为22.7%),对氨基糖苷类药物庆大霉素、妥布霉素、阿米卡星的耐药率分别为17.5%、17.5%和13.0%,对青霉素类药物的耐药率>40.4%(除哌拉西林为26.2%),对含β-内酰胺酶抑制剂复合物的耐药率差异较大,哌拉西林/他唑巴坦为17.0%,而氨苄西林/舒巴坦为98.6%;对碳青霉烯类药物亚胺培南和美罗培南的耐药率分别为24.6%和26.0%;127株耐环丙沙星铜绿假单胞菌的耐药性明显升高,对左氧氟沙星的耐药率为86.6%,对第三代头孢菌素的耐药率上升至>61.4%,对第四代头孢菌素头孢吡肟的耐药率由20.3%上升至62.2%,对含β-内酰胺酶抑制剂复合物的耐药率从17.0%上升至>49.6%,对氨基糖苷类药物庆大霉素、妥布霉素的耐药率上升至>64.6%,对阿米卡星的耐药率由13.0%上升至48.8%;耐环丙沙星铜绿假单胞菌中未检出qnrS基因和qnrC基因,qnrA、qnrB、qnrD、qepA和aac(6′)-Ib-cr的阳性率分别为31.2%、87.5%、15.6%、10.9%、39.1%。结论临床分离的耐环丙沙星铜绿假单胞菌携带qnrA、qnrB、qnrD、qepA和aac(6′)-Ib-cr基因,未检出qnrS、qnrC基因;qnr、qepA和aac(6′)-Ib-cr基因是质粒介导的铜绿假单胞菌耐环丙沙星的主要机制。OBJECTIVE To study the drug resistance and detect plasmid-mediated ciprofloxacin-resistant genes in clinical isolates of Pseudomonas aeruginosa, and study the molecular resistant mechanisms. METHODS The clinical isolates were identified by the automatic VITEK 2 system and the antimicrobial susceptibility was tested by K-B disc diffusion. The quinolone-resistant genes mediated by plasmids including qnrA, qnrB, qnrC, qnrD, qnrS, qepA and aac （6＇）-Ib-cr were analyzed by polymerase chain reaction. RESULTS The resistance rates of 423 isolates of P. aeruginosa to ciprofloxacin and levofloxacin were 23.2%, the resistance rates to the first and third generation of cephalosporins were higher than 49. 2% except 22. 7% to ceftazidime, the resistance rates to aminoglycoside antibiotics such as gentamicin, tobramycin, and amikacin were 17. 5%, 17. 5% and 13. 0%, respectively） the drug resistance rates to penicillins were higher than 40. 4% except 26.2% to piperacillin, there was large difference in the resistant rate to ^-lactamase inhibitor combinations, piperacillin/tazobactam （17. 0 %） and ampicillin/sulbactam （98.6%）; the resistance rates to imipenem and meropenem were 24. 6% and 26.0%, respectively） of 127 strains of ciprofloxacin-resistant p. aeruginosa isolates, the drug resistance increased significantly, the resistance rate to levofloxacin was 86. 6%, the resistance rate to the third generation of cephalosporin rose above 61.4%, the resistance rate to the fourth generation of cephalosporin cefepime rose from 20.3% to 62. 2%;the resistance rate to ^-lactamase inhibitor complexes increased from 17. 0% to 49. 6% or above, and the resistance rates to aminog[ycosides （gentamicin, tohramycin） rose to 64. 6% or above, the resistance rate to amikacin increased from 13.0% to 48.8%） there were no qnrS and qnrC that were detected in ciprofloxacin-resistant p. aeruginosa, the positive rates of qnrA, qnrB, qnrD, qepA and aac（6/）-Ib-cr gene were 31.2%, 87. 5%, 15.6%, 10.9%, and 39.1%, respectively

关 键 词：铜绿假单胞菌 环丙沙星 耐药 机制 

分 类 号：R378.991[医药卫生—病原生物学]