In vitro susceptiiblity of Mycobacterium fortuitum and Mycobacterium chelonei to amikacin.

Infections due to Runyon group IV atypical mycobacteria, Mycobacterium fortuitum and Mycobacterium chelonei, in humans have been difficult to treat in the past because of the organisms' resistance to all of the conventional antimycobacterial drugs. Determinations of minimal inhibitory concentrations (MICs) by the agar dilution method suggest that amikacin may be useful in the treatment of infections due to M. fortuitum and M. chelonei. Further support for the efficacy of antimicrobial agents with good in vitro activity in the treatment of infections with M. fortuitum and M. chelonei will depend on correlation of future clinical experience with standardized data on the MICs for these organisms.