Sensitivity of opportunist mycobacteria to rifampicin and ethambutol.
A total of 1237 strains of opportunist mycobacteria were tested for sensitivity to rifampicin and ethambutol. Most strains of Mycobacterium kansasii and all strains of M. marinum tested were sensitive to both drugs. A variable pattern was given by M. xenopi strains, but a general resistance was observed with the M. avium--intracellulare--scrofulaceum group. All strains of M. fortuitum and M. chelonei were highly resistant. Scotochromogens were mostly sensitive to ethambutol, but there was variable resistance to rifampicin. These properties may be useful in identification of species. No acquired resistance was found in follow-up cultures from confirmed cases of mycobacterioses, but details of therapy, if any, were not known.
D004352:Drug Resistance, Microbial; D004977:Ethambutol / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009161:Mycobacterium / Q000187:drug effects*; D009170:Nontuberculous Mycobacteria / Q000187:drug effects*; D012293:Rifampin / Q000494:pharmacology*
D004977:Ethambutol; D012293:Rifampin