In-vitro activity of clinafloxacin (CI-960) and PD 131628-2 against anaerobic bacteria.
The antimicrobial activities of two new quinolones, CI-960 and PD 131628-2 were determined against 339 strains of anaerobic bacteria and compared to cefoxitin, imipenem and metronidazole. The NCCLS-approved Wadsworth agar dilution technique with Brucella-lysed blood agar was used throughout the study. Breakpoints of the new quinolones are 2 mg/L, and breakpoints for cefoxitin, imipenem and metronidazole are 32, 8 and 16 mg/L, respectively. CI-960 displayed excellent activity, inhibiting all strains tested at 1 mg/L. PD 131628-2 inhibited 94% of Bacteroides fragilis, 75% of other B. fragilis group isolates, 87% of Prevotella spp, 79% of the Fusobacterium mortiferum-varium group, 74% of non-sporing gram-positive bacilli, and 89-100% of Clostridium spp other than Clostridium difficile at 2 mg/L. None of the eight strains of C. difficile was inhibited at 2 mg/L although they were inhibited at 4 mg/L. PD 131628-2 inhibited all strains of other Bacteroides spp, Porphyromonas spp, and Fusobacterium nucleatum at < or = 1 mg/L.
Wexler
H M
HM
Research Service Veterans Administration Medical Center, West Los Angeles, Wadsworth Division, California 90073.
Molitoris
E
E
Reeves
D
D
Finegold
S M
SM
D000890:Anti-Infective Agents / Q000494:pharmacology*; D001421:Bacteria, Anaerobic / Q000187:drug effects*; D001424:Bacterial Infections / Q000382:microbiology; D003470:Culture Media; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests; D009287:Naphthyridines / Q000494:pharmacology*; D015363:Quinolones / Q000494:pharmacology*
D000890:Anti-Infective Agents; D003470:Culture Media; D024841:Fluoroquinolones; D009287:Naphthyridines; D015363:Quinolones; C068217:PD 131628; C057477:clinafloxacin