摘要目的 探讨多药耐药鲍曼不动杆菌(multi-drug resistant Acinetobacter baumannii,MDR-ABA)对氯霉素、利福平、四环素和复方磺胺甲恶唑等广谱抗菌药物的耐药性,并进行耐药相关基因分析.方法 临床分离62株MDR-ABA,采用K-B纸片扩散法测定它们对22种抗菌药物的敏感性,并用PCR及序列分析法检测氯霉素耐药相关基因catB、cmlA.利福平耐药相关基因arr-2/3,四环素耐药相关基因tetA、tetB,复方磺胺甲恶唑耐药相关基因sul1、dfrA1、dfrA5、dfrA7/17、dfrA12和dfrB5,抗菌化合物外排泵蛋白基因tehA、emrB、emrD、emrE、smr-2和其他广谱的抗菌药物外排泵mafA基因等17种基因.结果 62株MDR-ABA对氯霉素、利福平、四环素和复方磺胺甲恶唑的耐药率分别为100.0%(62/62)、100.0%(62/62)、90.3%(56/62)和82.3%(51/62),mafA、tetB、sull和tehA基因阳性株数和阳性率分别为62株(100.0%)、46株(74.2%)、36株(58.1%)和8株(12.9%),其余13种基因均为阴性.任选2株tetB、sull、tehA和mdfA基因阳性菌株进行DNA测序,并作BLASTn比对,与已登录于美国GenBank的序列一致.结论 MDR-ABA临床分离株对氯霉素、利福平、四环素和复方磺胺甲恶唑等广谱抗菌药物的耐药性很高,其多药耐药表型与携带mayA基因密切相关.

abstractsObjective To investigate ehloramphenicol,tetracycline,rifampicin and trimethoprimsulfamethoxazole resistance and the related genes in multi-drug resistant Acinetobacter baumannii(MDR-ABA).Methods Sixty-two strains of MDR-ABA were isolated from clinical samples,and their susceptibilities to 22 antimicrobial agents were detected by Kirby-Bauer disk diffusion tests.Genes related to chloramphenicol(catB and cmlA),rifampicin(arr-2/3),tetracycline(tetA and tetB)and trimethoprimsulfamethoxazole(sull,dfrA1,dfrA5,dfrA7/17,dfrA12,dfr85)resistance and drug emux genes(tehA,emrB,emrD,emrE,smr-2,mdfA)were analyzed by PCR and verified by DNA sequencing.Results Resistant rates of these MDR-ABAs to chloramphenicol,rifampicin,tetracycline and trimethoprimsulfamethoxazole were 100.0%(62/62),100.0%(62/62),90.3%(56/62)and 82.3%(51/62)respectively,while62 strains(100.0%),46 strains(74.2%),36 strains(58.1%)and 8 strains (12.9%)were detected to carry mafA,tetB,sull and tehA genes,respectively.The lest 13 genes were all negative.tetB,sull,tehA and mafa genes(2 for each)chosen optionally from positive ones were verified by DNA sequencing and BLASTn.and all were identified as the same sequences in GenBank.Conclusions MDR-ABAs show hish resistance to chloramphenicol,tetracycline, rifampiein and trimethoprimsulfamethoxazole.Multi-drug resistant phenotypes of MDR-ABAs may be closely related to mdfA genes harboring in strains.