氨曲南联合环丙沙星或美罗培南对多耐药铜绿假单胞菌体外药敏研究

In vitro drug sensitivity study of aztreonam combined with meropenem or ciprofloxacin to multidrug resistant pseudomonas aeruginosa

目的探讨氨曲南(aztreonam,ATM)与环丙沙星(ciprofloxacin,CIP)、美罗培南(meropenem,MEM)联合应用对多耐药铜绿假单胞菌(multidrug resistant pseudomonas aeruginosa,MDRPA)的体外抑菌效果。方法收集解放军总医院老年病房2018~2019年分离的MDRPA共62株,采用琼脂平板稀释法,应用棋盘法设计检测不同药物组合对MDRPA的最低抑菌浓度(minimum inhibitory concentration,MIC),通过计算分级抑菌浓度指数(fractional inhibitory concentration,FIC)判断联合用药组合对MDRPA的体外抑菌活性。结果ATM与CIP联合后,16.1%表现为协同作用,38.7%为相加作用,43.6%为无关作用,1.6%为拮抗作用;ATM与MEM联用后,3.2%为协同作用,41.9%为相加作用,53.3%为无关作用,1.6%为拮抗作用。上述药物联合应用后,各药MIC50均较前降低,浓度-累积抑菌率曲线较单独应用表现为左移。结论ATM与CIP联用可以提高各自对MDRPA抗菌作用的敏感性,效果优于ATM与MEM联用。

Objective To evaluate the combined inhibitory effect of aztreonam(ATM)and ciprofloxacin(CIP),aztreonam(ATM)and meropenem(MEM)respectively on clinically isolated multidrug resistant pseudomonas aeruginosa(MDRPA)strains in vitro.Methods A total of 62 MDRPA strains isolated from the Second Medical Center of Chinese PLA Genneral Hospital between 2018 and 2019 were collected.Combined inhibitory effect of ATM and MEM,ATM and CIP in vitro was assayed by detecting the minimum inhibitory concentration and calculating the fractional inhibitory concentration(FIC)index for 62 MDRPA strains with the agar dilution method.Results Combined ATM and CIP displayed 16.1%synergic effect,38.7%additive effect,43.6%unrelated effect and 1.6%antagonistic effect on MDRPA strains.Combined ATM and MEM showed 3.2%synergic effect,41.9%additive effect,53.3%unrelated effect,1.6%antagonistic effect on MDRPA strains.The MIC50 of these drugs was significantly lower when they were used in combination with their concentration-accumulative inhibition curves shifted to the left.Conclusion Combined ATM and CIP shows a combined synergic and additive inhibitory effect on MDRPA strains in vitro,that is better than the effect of combined ATM and MEM.