Journal of Antimicrobial Chemotherapy (1986) 18, 163-169
© 1986 The British Society for Antimicrobial Chemotherapy
research-article |
The in-vitro activity of CI-934 compared with that of other new 4-quinolones and nalidixic acid
Department of Microbiology, United Medical and Dental Schools of Guy's and St Thomas's Hospitals, St Thomas's Campus London SE1 7EH, England
accepted 10 February 1986
The in-vitro activity of CI-934, a new 4-quinolone compound, was compared with that of the other new 4-quinolones, enoxacin and ciprofloxacin, and also with that of nalidixic acid.
CI-934 was more active than any of the other 4-quinolones tested against Grampositive aerobic organisms including Staphylococcus aureus (MICs 0.06–0.25 mg/1).ß-haemolytic streptococci (MICs 0.12–0.5 mg/1), Streptococcus pneumoniae (MICs 0.25–0.5 m1/1), viridans streptococci (MICs 0.06–0.5 mg/1) and most enterococci (MICs 0.12–0.5 mg/1), although some ampicillin-resistant isolates of Strm faecium were slightly less susceptible (MICs 2 mg/1).
All three of the newer 4-quinolones tested were highly active against Enterobacteriaceae, Aeromonas sp., Haemophilus influenzae and Neisseria gonorrhoeae (MICs mostly < 1 mg/1). The other Gram-negative aerobes tested were in general somewhat less susceptible, although for Acinetobacter and Pseudomonas aeruginosa MICs seldom exceeded 8 mg/1. CI-934 was more active than enoxacin against Gardnerella vaginalis (MICs 1–8 mg/1) although it was a little less active than ciprofloxacin.
Bacteroides species (including about half of the fragilis group) were susceptible to CI-934 (MICs mostly 1–8 mg/1): ciprofloxacin had similar activity but enoxacin was less active. Other anaerobes tested were mostly highly susceptible to CI-934 (MICs 1 mg/1 or less) but were somewhat less susceptible to enoxacin and ciprofloxacin.