title: Clarithromycin minimal inhibitory and bactericidal concentrations against Mycobacterium avium.
abstract: Minimal inhibitory and bactericidal concentrations (MIC and MBC) of clarithromycin were determined with 49 Mycobacterium avium strains isolated from patients with acquired immunodeficiency syndrome. The inhibitory activity depended on the pH of the medium: the drug was more active at pH 7.4 and less active at pH 5.0, with activity at pH 6.8 in an intermediate position. The broth-determined MIC found at pH 7.4 were 0.25 and 0.5 micrograms/ml for most strains. The agar-determined MIC for most strains ranged from 1.0 to 4.0 micrograms/ml. The MBC of the drug were 8- to 64-fold higher than the MIC, which indicates that the efficacy of clarithromycin can be associated with its inhibitory rather than its bactericidal activity.
authors.affiliation: National Jewish Center for Immunology and Respiratory Medicine, University of Colorado Health Sciences Center, Denver.
authors.forename: L B
authors.initials: LB
authors.lastname: Heifets
authors.forename: P J
authors.initials: PJ
authors.lastname: Lindholm-Levy
authors.forename: R D
authors.initials: RD
authors.lastname: Comstock
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000382:microbiology; D017291:Clarithromycin; D003470:Culture Media; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008826:Microbial Sensitivity Tests; D015269:Mycobacterium avium Complex / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D003470:Culture Media; D004917:Erythromycin; D017291:Clarithromycin