Combined versus single antituberculosis drugs on the in vitro sensitivity patterns of non-tuberculous mycobacteria.
- 1 November 1987
- Vol. 42 (11), 838-842
- https://doi.org/10.1136/thx.42.11.838
Abstract
Drug sensitivity tests were performed for ethambutol, rifampicin, streptomycin, and isoniazid both alone and in paired combinations, on 16 strains of Mycobacterium avium intracellulare, seven strains of Mycobacterium xenopi, and eight strains of Mycobacterium malmoense. Most strains were resistant to the individual drugs, but all strains of M. malmoense, 86% of M. xenopi, and 31% of M. avium intracellulare were completely suppressed by the lowest concentrations of ethambutol and rifampicin when the two drugs were combined in vitro. Streptomycin combined with ethambutol or with rifampicin in the lowest combined concentrations suppressed 50% and 62% respectively of strains of M. malmoense. All strains of M. xenopi were suppressed by the lowest combined concentrations of streptomycin with rifampicin. Combinations with isoniazid were less effective. It is postulated that similar effects in vivo might account for the satisfactory clinical response seen in patients with disease caused by these mycobacteria who have received treatment with combinations of standard antituberculosis drugs despite in vitro resistance to the individual agents.This publication has 5 references indexed in Scilit:
- Pulmonary infection with mycobacterium malmoense—A review of treatment and responseTubercle, 1985
- Pulmonary infection with mycobacterium xenopi: review of treatment and response.Thorax, 1984
- Treatment of pulmonary infections caused by mycobacteria of the Mycobacterium avium-intracellulare complex.Thorax, 1981
- A Method for Testing for Synergy with Any Number of AgentsThe Journal of Infectious Diseases, 1978
- The design of sensitivity tests on tubercle bacilliTubercle, 1961