INVITRO SYNERGISTIC ACTIVITY BETWEEN OFLOXACIN AND ANSAMYCIN AGAINST MYCOBACTERIUM-LEPRAE

The antimicrobial effects of ofloxacin, alone and in combination with either rifampicin or rifabutin, were evaluated against M. leprae, using in vitro cell-free culture system. The minimum inhibitory concentration (MIC) of ofloxacin against M. leprae was 15 mug/ml, while MICs of rifampicin and rifabutin were 0.4 and 0.2 mug/ml, respectively. Combination of 0.375 mug/ml ofloxacin and 0.05 mug/ml of rifabutin exhibited synergistic bactericidal activity while the effect of combination of 0.75 mug/ml ofloxacin and 0.2 mug/ml rifampicin was additive bactericidal. Thus, combination of ofloxacin and rifabutin deserves further attention in multi-drug therapy of leprosy.