莫西沙星对耐药葡萄球菌生物膜药效学研究

目的：研究莫西沙星对4株临床耐药葡萄球菌生物膜的体外药效学。方法：采用微量肉汤稀释法测定莫西沙星的最低抑菌浓度（Minimal inhibitory concentration，MIC）、最低抑制生物被膜浓度（Minimal biofilm inhibitory concentration，MBIC）和最低摧毁生物被膜浓度（minimal biofilm eradication concentration，MBEC）；测定莫西沙星对细菌生物膜形成量以及存活菌的影响；采用微量稀释棋盘法测定莫西沙星与局部用药瑞他帕林的联合抗生物膜效果。结果：莫西沙星在16~256mg/L的范围内可完全摧毁细菌生物膜；2 × MIC显著降低生物被膜的形成量；100 × MIC可显著降低生物被膜存活菌数；与瑞他帕林的联合抗生物膜分数（fractional biofilm inhibitory concentration，FBIC）均小于1.0。结论：莫西沙星对4株临床耐药葡萄球菌生物被膜具有抑制和摧毁作用，而且与局部用药瑞他帕林具有协同作用。

Activity of Moxifloxacin against Resistant Staphylococcus Biofilms in Vitro

Objective To investigate the antibacterial effect of moxifloxacin against 4 strains of clinical resistant Staphylococcus biofilms in vitro. Methods MIC (Minimal inhibitory concentrations), MBIC (Minimal biofilm inhibitory concentration) and MBEC (minimal biofilm eradication concentration) were examined by microdilution in broth; the percentages of biofilm formed, the counting of viable cells of biofilms were investigated and synergy testing against biofilms by microdilution checkerboard method were evaluated. Results Moxifloxacin can eradicat biofilms at the concentration of 16~256mg/L; The biofilm formed significantly decreased with moxifloxacin at 2 × MIC; moxifloxacin at 100 × MIC caused significantly decrease in viable cells of biofilms; the fractional biofilm inhibitory concentrations (FBICs) of moxifloxacin in combination with topical antibiotic moxifloxacin were all less than 1.0. Conclusions Moxifloxacin can inhibite and eradicate clinical resistant Staphylococcus biofilms in vitro; synergy was demonstrated for moxifloxacin in combination with topical antibiotic retapamulin against them.