双黄连联合左氧氟沙星对耐甲氧西林金黄色葡萄球菌的体外抗菌活性

Study on the antibacterial activity of levofloxacin combined with Shuanghuanglian against MRSA

目的：评价双黄连与左氧氟沙星联合应用耐甲氧西林金黄色葡萄球菌（MRSA）的体外抗菌作用。方法：采用棋盘法设计，微量肉汤稀释法测定其MIC值，计算FIC指数。结果：左氧氟沙星与双黄连联合应用后，左氧氟沙星对MRSA的MIC值均有下降。同样，双黄连对MRSA的MK值亦有下降。FIC指数范围主要在0～1。结论：左氧氟沙星与双黄连联合应用，对MRSA的体外联合抗菌作用主以相加为主。

OBJECTIVE To evaluate the antibiotic effects of levofloxacin combined with Shuanghuanglian against methicillinresistant Staphylococcus aureus （MRSA）. METHODS The protocol was designed by checkerboard method and the MICs of levofloxacin alone or combined with Shuanghuangiian against MRSA were determined by broth dilution method. The FIC index was calculated according to MIC results. RESULTS When levofloxacin combined with Shuanghuanglian, the MIC of levofloxacin against MRSA was reduced significantly. The MIC of Shuanghuanglian against the test bacteria was reduced significantly also. The range of the FIC index was mainly between 0-1. CONCLUSION The results suggested that additive effect of the antibacterial activity of levofloxacin combined with Shuanghuanglian against MRSA was the main action in this study.