摘要
目的探讨1株多药耐药鲍氏不动杆菌(MDR-ABA)对7类抗菌药物的耐药机制。方法采用K-B纸片扩散法或E-test法测定23种抗菌药物的敏感性,用聚合酶链反应(PCR)及序列分析的方法检测7类抗菌药物耐药相关基因和多种药物外排泵基因以及质粒、转座子与整合子等遗传标记,同时采用改良三维试验法检测超广谱β-内酰胺酶(ESBLs)、头孢菌素酶(AmpC)和金属β-内酰胺酶(MBL)活性。结果该MDR-ABA除对多黏菌素B和头孢哌酮/舒巴坦敏感以外,其余21种抗菌药物均为耐药,共检出TEM-1、OXA-23、ADCt、etB、mdfA、tehA、qacE△1-sul1t、npUt、np513I、Saba1、gyrA突变等11种耐药基因及遗传标记,ESBLs和AmpC酶检测均为阳性。结论携带多种耐药基因和多种药物外排泵基因mdfAt、ehA是该菌株对7类抗菌药物耐药的原因,同时该菌株携带多种可移动遗传元件,极易造成耐药基因的水平转移。
OBJECTIVE To investigate the mechanisms of drug resistance to 7 classes of antibiotics in a multidrug-resistant strain of Acinetobacter baumannii（MDR-ABA）.METHODS Drug susceptibility to 23 kinds of antimicrobial agents was detected by K-B disk diffusion tests or E-test.Then,7 kinds of antibiotic resistant genes and drug efflux genes and genetic markers（conjugal plasmids and transposons and integrons）were analyzed by PCR and verified by DNA sequencing,and activities of beta-lactamases,such as extended spectrum beta-lactamases（ESBLs）,cephalosporinase（AmpC）and metallo-beta-lactamases（MBL） were detected by the modified three-dimensional test using enzyme extraction.RESULTS The strain of MDR-ABA was susceptible to polymyxine and cefoperazone/sulbactam,but resistant to other 21 kinds of antimicrobial agents.And 11 kinds of resistant genes and genetic markers were detected TEM-1,OXA-23,ADC,tetB,mdfA,tehA,qacE△1-sul1,tnpU,tnp513,ISaba1,and gyrA mutation.However,the ESBLs and AmpC were produced together.CONCLUSIONS The strain shows drug resistance to 7 classes of antibiotics result from some kinds of resistant genes and genetic markers as well as drug efflux genes mdfA and tehA harboring on it.Furthermore,some kinds of mobile genetic elements harboring on the strain are prone to lead to horizontal dissemination of resistant genes and genetic markers.
出处
《中华医院感染学杂志》
CAS
CSCD
北大核心
2010年第15期2184-2188,共5页
Chinese Journal of Nosocomiology
基金
杭州市科技发展计划项目(20090833B35)
杭州市卫生科技计划项目(2008B0113)
杭州市余杭区重大科技项目(2008001)
关键词
鲍氏不动杆菌
多药耐药
耐药基因
可移动遗传元件
Acinetobacter baumannii
Multi-drug resistance
Resistant gene
Mobile genetic element
