多重耐药铜绿假单胞菌防突变浓度及突变选择窗分析

Analysis of mutant prevention concentration and mutant selection window against multidrug-resistant pseudomonas aeruginosa

目的:探讨阿米卡星(AMK)、异帕米星(ISP)与哌拉西林/他唑巴坦(TZP)联合对临床分离的多重耐药铜绿假单胞菌(multidrug-resistant pseudomonas aeruginosa,MRPA)防突变浓度(mutant prevention concentration,MPC),突变选择窗(mutant selection window,MSW)的影响,为临床合理使用抗生素,防止细菌耐药突变株产生提供理论依据。方法:琼脂稀释法分别测定AMK、ISP、TZP对临床分离的MRPA的MIC;微量肉汤稀释法测定AMK联合TZP、ISP联合TZP后对MRPA的MIC;琼脂稀释法测定AMK、ISP单独应用或与TZP联合用药对MRPA的MPC,并计算MSW。结果:两药联用组比单药组均能显著降低MPC值(P<0.05)。突变选择窗(MSW)以缩小为主。结论:AMK、ISP分别与TZP联合应用能够降低AMK、ISP对MRPA的MPC、MSW,联合用药有利于防止耐药突变的发生。

Objective： To explore the influence of combined detection of Amikacin, Isepamicin and piperacillin - tazobactam on MPC and MSW of MRPA isolates in clinic, and provide the laboratory evidence for preventing anti-biotics resistance, guiding antibiotic therapy and controlling nosocomial infections. Methods ： 1. The MICs of Ami- kacin, Isepamicin and piperacillin - tazobactam against the MRPA isolates were determined by agar dilution method ; 2. MICs of Amikacin combining with piperacillin -tazobactam（ AMK/TZP）, Isepamicin combining with piperacillin - tazobactam（ISP/TZP） against the MRPA were determined in cation - supplemented M - H broth using the micro -dilution technique; 3. The MPCs of Amikacin, Isepamicin alone and both combination with piperacillin - tazobactam separately against the MRPA were determined by agar plates dilution method. Results： I. The MPC decreased evidently in drug combination than single drug use; 2. Compared with drug use alone, MSW narrowed obviously in drug combination. Conclusion： Combination with TZP could decrease the MPC and MSW of AMK, ISP alone against MRPA, and this decrease can improve the ability of preventing drug resistance development and reducing the selective enrichment of resistant mutants.