In vitro activities of aminoglycosides, lincosamides, and rifamycins against Mycobacterium leprae.

The in vitro activities of a variety of aminoglycosides, lincosamides, and rifamycins against Mycobacterium leprae were evaluated with the BACTEC 460 system. At 20 micrograms/ml, gentamicin, kanamycin, tobramycin, streptomycin, and amikacin were inactive. Lincomycin was active at 20 micrograms/ml, and clindamycin was active at 0.31 micrograms/ml. Rifamycin SV, rifabutin, and rifampin were active at 3.1, 3.1 to 12.5, and 200 ng/ml, respectively. The in vitro assay correlates well with the in vivo response of M. leprae to antimicrobial agents, with the exception of the aminoglycosides.