摘要
目的分析本院耐亚胺培南铜绿假单胞菌(imipenem resistant Pseudomonas aeruginosa,IRPA)对临床常用抗菌药物的耐药性及所产β-内酰胺酶类型,用以指导临床更有效地使用抗生素。方法按2005年NCCLS的标准用纸片扩散(K-B)法测定美洛培南等12种临床常见抗菌药物对32株耐亚胺培南铜绿假单胞菌的体外抗菌活性,三维试验、改良三维试验、2-巯基丙酸抑制试验分析β-内酰胺酶类型。结果32株细菌均为多重耐药株,敏感率居前三位的分别是头孢他啶(42.2%),头孢吡肟(36.5%)、哌拉西林(33.5%)、其次为哌拉西林/三唑巴坦、头孢哌酮,舒巴坦,头孢哌酮,敏感率依次为33 3%、31.2%、24.6%。美洛培南敏感率为9.3%,中介率为23.2%。三维试验结果表明6株产碳青霉烯酶,其中1株产金属酶,2-巯基丙酸抑制试验筛选金属酶仅1株阳性,与三维试验结果一致,2株能被氯唑西林抑制,可能是AmpC酶的变异子,另3株均不能被克拉维酸、氯唑西林、EDTA抑制,其余菌株中有2株产AmpC酶,3株产超广谱β-内酰胺酶(ESBLs),4株同时产AmpC酶和ESBLs。结论我院铜绿假单胞菌对亚胺培南耐药机制可能以外膜孔蛋白丢失或主动泵出系统过度表达为主,不是以产碳青霉烯酶为主。
Objective To study the clinical antibiotic resistance and β-laetanmses of imipenem-resistoalt pseudomonas aeruginosa （IRPA） for guiding the effective use of antibiotics in clinical practice. Methods Disk-diffusiou （K-B） method was used to test in vitro antimicrobial activty of meropcncm and other 11 untimicrbiadls against 32 strains of IRPA according to the standards of NCCIS （2005）, three-dinensional test, modifiled three-dinmnsion＇al test and 2-mercaptoproptmoic acid inhibited assays were used to c characterize β-lactanmses which produced by these strains. Results 32 strains were all multidrugrasistant, and according to their susceptibility rates to the 12 antimicrobials, the first three oues were ceftazidime （42.2%）, cefepime （36.5%） and piperacillin （33.5%）, and the next were piperacillin/tazobactam （33.3%）, cefoperazone/sulbactam （31.2%） and cefoperazone （24.6%）. The susceptibility rate to meropenem was 9.3%, and intermediate rate was 23.2%. There-dimensional test indicated 6 strains produced cabapenemases, 1 strain produced metallo-β-1actamase; 2-mercaptqawpanoic acid inhibited assays indicated only 1 strains produced metallo-β-lactamase, which was in agreenvent with the result of three-dimensional test, 2 strains which produced carbapenemases could be inhibited by cloxacililin, another 3 strains which produced carbapenemasas could not be inhibited by clavulanic acid, cloxacillin or EDTA. In the other strains, 2 strains produced AmpC enzymes. 3 strairs produced extended-spectrum β-lactamases （ESBLs）, and 4 strains produced AmpC enzymes and ESBLs. Condusions Efllux systems or the loss DprD might be the main mechanisms for iraipenem resistant in pseudonmnas aemglnnsa in our hospital, the production of carbapenemases was not the main mechanism.
出处
《浙江预防医学》
2007年第11期10-12,共3页
Zhejiang Journal of Preventive Medicine
