In vitro Antimicrobial Activity of Fusidic Acid Aga in Staphylococcus Aureus

Objective To study the resistance and the resistant change of Staphylococcus au reus to fusidic acid.Methods The minimal inhibitory concentration(MIC) of 220 S.aureus strains in 2007 and 260 S.aureus strains in 2010 were determined against fusidic acid by agar dilution method.The sensitivity to other antibiotics was determined in disc-diffusion method.Results The rate of resistance of 480 S.aureus strains to fusidic acid were 1.3%.The MIC50 and MIC90 were 0.25mg/L and 0.5 mg/L,respectively,between 2007 and 2010.No strains were resistant to vancomycin.The rate of resistance of strains in 2007 to meticillin was 57.8% and it was 76.9% in 2010.Conclusion Fusidic acid appears to have fine antimicrobial activity against S.aureus,and the activiity hasn't change in 2007 and 2010.