Abstract: Objective To value the effective and safety therapy of community breast abscess by MRSA infection that treated with rifampin plus levofloxacin and the therapy of its mechanism. Methods From January 2010 to December 2018,there were 86 breast abscess by MRSA infected. All the cases were divided into levofloxacin + rifampicin treatment group and vancomycin treatment group. The cure rate, the clearance rate of MRSA, treatment time, antimicrobial treatment cost and the adverse reactions of antibiotics were observed. The evofloxacin agar plate,rifampicinagar plate, levofloxacin combined with rifampicin agar plate were made respectively. The concentration of all the agar plates changed gradiently. And the MIC, MPV and MSW of each agar plate was cheeked. Results The cure rate of levofloxacin + rifampicin treatment group and vancomycin were 93% and 97% respectively（P>0.05）. MRSA clearance rate were 100% of two group. The treatment time of levofloxacin + rifampicin treatment group and vancomycin were 8.8 and 9.1 days respectively（P>0.05）. Antimicrobial cost of levofloxacin + rifampicin treatment group and vancomycin were 700 yuan and 2000 yuan respectively（P<0.05）. The incidence of adverse drug reactions rate of evofloxacin + rifampicin was 11.4%; incidence of adverse drug reactions rate of vancomycin was 12.2% （P>0.05）. Bacteria in vitro experiments show that levofloxacin and rifampicin can shrink their MIC, MSW, and MPV. The rifampicin was more obvious. Conclusion The patients who got breast abscess that infected by MRSA in community, treated with Rifampin combined with Levofloxacin therapy could get high cure rate,low cost,less side effects.It could be used as one of the important treatment of clinicians. Rifampin combined with Levofloxacin can reduce the MPV and narrow its MSW to treat MRSA.And it may be the important mechanism of the rifampin combined with Levofloxacin to treat MRSA.

Key words: lactationperiod, rifampin, Methicillin-resistant Staphylococcus aureus, breast abscess, Levofloxacin

摘要： 目的 总结利福平加左氧氟沙星治疗乳腺脓肿社区耐甲氧西林金黄色葡萄球菌（MRSA）感染的有效性、安全性及其机理研究。方法 收集2010年1月~2018年12月乳腺脓肿MRSA感染病例共86例,分为左氧氟沙星+利福平（左利组）、万古霉素（万古组）抗感染治疗组, 观察各组的治愈率、MRSA清除率、治疗时间、抗菌药物治疗费用及抗菌药物的不良反应;分别制作浓度梯度变化的左氧氟沙星、利福平及上述两药联合的琼脂M-H平皿,接种MRSA细菌后分别测定其最低抑菌浓度（MIC）、防耐药突变浓度（MPC）以及耐药突变选择窗（MSW）。结果 左利组和万古组治愈率分别93%、97%,无统计学差异（P>0.05）;MRSA清除率均为100%;治疗时间分别8.8、9.1天,无统计学差异（P>0.05）;抗菌素费用分别700元、2000元,有统计学差异（P<0.05）;左利组药物不良反应发生率11.4%,万古组12.2%,无统计学差异（P>0.05）。体外细菌实验表明左氧氟沙星和利福平联合应用,可以缩小各自对MRSA的MIC及MPV,缩窄MSW,其中利福平较为明显。结论 对于社区感染的乳腺脓肿MRSA感染患者,利福平联合左氧氟沙星治疗治愈率高、费用低、副作用少,可作为是临床医师重要选择之一;同时联合用药后降低其对MRSA的MPV,缩窄MSW是其抗菌的重要机理之一。

关键词: 利福平, 耐甲氧西林金黄色葡萄球菌, 哺乳期, 乳腺脓肿, 左氧氟沙星