左氧氟沙星联合清解剂抑制产生铜绿假单胞菌耐药菌的作用研究

目的研究左氧氟沙星联合清解剂对铜绿假单胞菌抑菌能力及防耐药突变浓度(mutant preventionconcentration,MPC)的影响。方法采用微量肉汤二倍稀释法测定左氧氟沙星、清解剂单独使用及两药联用的最低抑菌浓度(minimum inhibitory concentration,MIC)和防耐药变异浓度,并计算联合用药后的突变选择窗(mutant selectionwindows,MSW)。结果左氧氟沙星、清解剂单用对铜绿假单孢菌的MIC分别为1.0μg/m L、5.0 mg/m L,MPC分别为5.12μg/m L、200 mg/m L。左氧氟沙星与1MIC的清解剂联用后可使左氧氟沙星对铜绿假单胞菌的MIC降到0.5μg/m L,MPC下降至3.2μg/m L。结论左氧氟沙星与清解剂联用,具有相加作用,可以明显降低各自单独用药对铜绿假单胞菌的MIC及MPC。为优化临床用药方案、防止细菌耐药性突变株的产生提供一定的理论依据。

Effect of levofloxacin combined with Qingjie Ji on reducing resistant Pseudomonas aeruginosa

Objective To study the effect of levofloxacin combined with Qingjie Ji (a traditional Chinese herbal formula) on the antibacterial ability for Pseudomonas aeruginosa and mutant prevention concentration (MPC).Methods The minimal inhibitory concentrations (MICs) and the MPCs of levofloxacin,Qingjie Ji,and the combination of them were detected respectively by the broth dilution technique,and the mutant selection window (MSW) was calculated.Results The MICs of levofloxacin and Qingjie Ji for Pseudomonas aeruginosa were 1.0 μg/mL and 5.0 mg/mL,and the MPCs were 5.12 μg/mL and 200 mg/mL,respectively.With the combination of levofloxacin and Qingjie Ji,the MIC of Pseudomonas aeruginosa was 0.5 μg/mL,and the MPC was 3.2 μg/mL.Conclusion The combination of levofloxacin and Qingjie Ji has an additive effect.The combination can obviously decrease the MIC and MPC,and narrow MSW of Pseudomonas aeruginosa.