Study on Susceptibility of Mycoplasma Hominis to Five Macrolides Agents

Objective To determine the susceptibility of Mycoplasma hominis(Mh) to 14-membered(erythromycin、roxithromycin and clarithromycin),15-membered(azithromycin) and 16-membered(josamycin) macrolides,and to provide the basis for the rational use of antibiotics.Methods The MIC of five macrolides against 106 strains of Mh were determined using broth microdilution method.Results Among the five macrolides,josamycin were the most active agents against Mh with the MIC_(50) being 0.125 mg/L,MIC_(90) being 0.5 mg/L;roxithromycin、clarithromycin and azithromycin were less active against Mh with the MIC_(50) being 4 mg/L、32 mg/L and 64 mg/L,respectively and MIC_(90) being 32 mg/L、128 mg/L and 512 mg/L,respectively;Eryhthromycin had the least activity against Mh,with MIC_(50) and MIC_(90) being 64 mg/L and 512 mg/L. Conclusion The degree of resistance of Mh to different macrolides varied 16-membered macrolides such as josamycin is more active against Mh than 14-membered and 15-membered macrolides.