Activity of antibiotics against pigmented and unpigmented variants of Mycobacterium avium-intracellulare
Gevaudan, M.J.; Bollet, C.; Mallet, M.N.; de Micco, P.
Pathologie-Biologie 39(5): 429-435
1991
ISSN/ISBN: 0369-8114 PMID: 1652731 Document Number: 385777
Efficacy of various antibiotics: amikacin, rifampicin, rifabutin, ciprofloxacin, temafloxacin, erythromycin and clarithromycin was evaluated against pigmented and unpigmented variants of Mycobacterium avium complex isolated from patients with acquired immunodeficiency syndrome. The minimal inhibitory concentrations of antibiotics against unpigmented variants were multiplied by 2 to 16 compared to those of pigmented variants. Observations with intracellularly growing bacteria showed that unpigmented variants were more resistant to antibiotics than variants with a difference of approximately 0.25 a 0.3 log 10 in decrease of viable or bacterial counts. The combinations of temafloxacin or ciprofloxacin with rifabutin and amikacin were most effective against unpigmented variants.