title: Antimicrobial activities of clarithromycin, gatifloxacin and sitafloxacin, in combination with various antimycobacterial drugs against extracellular and intramacrophage Mycobacterium avium complex.
abstract: We studied the activities of clarithromycin and fluoroquinolones (gatifloxacin, sitafloxacin, levofloxacin) in combination with other antimycobacterial drugs against extracellular and intramacrophage Mycobacterium avium complex (MAC). Clarithromycin potentiated the activities of rifampicin and rifalazil against both extracellular and intramacrophage MAC. In contrast, all the test quinolones exhibited antagonistic effects against extracellular MAC when combined with either clarithromycin or rifamycins. Such an antagonism was not observed for the activity of these combinations against intramacrophage MAC. Combined effects were observed with combinations of these fluoroquinolones with either ethambutol or streptomycin. Similar profiles were seen for the activities of two-drug combinations of clarithromycin or fluoroquinolones with other drugs against intramacrophage MAC isolated from pulmonary and disseminated MAC infections.
authors.affiliation: Department of Microbiology and Immunology, Shimane Medical University, Izumo, 693-8501, Shimane, Japan. tomoioka@shimane-med.ac.jp
authors.forename: Haruaki
authors.initials: H
authors.lastname: Tomioka
authors.forename: Chiaki
authors.initials: C
authors.lastname: Sano
authors.forename: Katsumasa
authors.initials: K
authors.lastname: Sato
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shimizu
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D002460:Cell Line; D017291:Clarithromycin / Q000494:pharmacology*; D004353:Drug Evaluation, Preclinical; D004357:Drug Synergism; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D024841:Fluoroquinolones; D000077734:Gatifloxacin; D006801:Humans; D008264:Macrophages / Q000187:drug effects / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D015269:Mycobacterium avium Complex / Q000187:drug effects*
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; C076246:sitafloxacin; D017291:Clarithromycin; D000077734:Gatifloxacin