[Determination of antimycobacterial activities of fluoroquinolones against clinical isolates of Mycobacterium tuberculosis: comparative determination with egg-based Ogawa and agar-based Middlebrook 7H10 media].
The minimum inhibitory concentrations (MICs) to the fluoroquinolones, ofloxacin (OFLX), ciprofloxacin (CPFX), sparfloxacin (SPFX), norfloxacin (NFLX), balofloxacin (BLFX) and CS-940, were determined in 100 clinical isolates of Mycobacterium tuberculosis. The MICs were determined with 1% egg-based Ogawa or agar-based Middlebrook 7H10 and each of them supplemented with oxidation-reduction color dye, 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC) by using the microculture technique. The MICs determined with Ogawa medium were approximately two- to four-fold higher when compared to those determined with Middlebrook agar medium. The supplement with STC slightly increased the MICs, probably as a result of easily recognizing small initial colonies. Among the six fluoroquinolones, CS-940 and SPFX showed the greatest antimycobacterial activities with inhibition of 50% of all the isolates at the concentrations between 0.25 to 0.5 microgram/ml. OFLX, CPFX and BLFX followed in potency at 0.5 to 2.0 micrograms /ml. NFLX was less potent requiring 8 to 16 micrograms/ml to inhibit 50% of the isolates.
Yamane
N
N
Department of Laboratory Medicine, Kumamoto University Medical School, Japan.
Chilima
B Z
BZ
Tosaka
M
M
Okazawa
Y
Y
Tanno
K
K
D000890:Anti-Infective Agents / Q000494:pharmacology*; D000995:Antitubercular Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology; D003470:Culture Media; D024841:Fluoroquinolones; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D009643:Norfloxacin / Q000494:pharmacology; D015242:Ofloxacin / Q000494:pharmacology; D015363:Quinolones / Q000494:pharmacology
D000890:Anti-Infective Agents; D000995:Antitubercular Agents; D003470:Culture Media; D024841:Fluoroquinolones; D015363:Quinolones; D002939:Ciprofloxacin; D015242:Ofloxacin; D009643:Norfloxacin; C077155:balofloxacin; C061363:sparfloxacin