Susceptibility of bacterial isolates to gatifloxacin and ciprofloxacin from clinical trials 1997-1998.
MICs of gatifloxacin and ciprofloxacin against 3482 pre-treatment, clinical trial isolates collected during 1997-1998 are reported. These data suggested that gatifloxacin was four- to eight-fold more active than ciprofloxacin against Gram-positive bacteria, with gatifloxacin MIC(90)s < or = 0.33 mg/l against Staphylococcus aureus and Streptococcus pneumoniae, and < or = 1.0 mg/l versus viridans streptococci and Enterococcus faecalis. Both quinolones had similar MIC(90)s versus Enterobacteriaceae (generally < or = 0.38 mg/l, except 0. 7-0.8 mg/l for Citrobacter freundii) and Pseudomonas aeruginosa ( approximately 8 mg/l). A total of 78% P. aeruginosa had gatifloxacin MICs < or = 2 mg/l. Gatifloxacin was more active than ciprofloxacin against Acinetobacter species and non-P. aeruginosa pseudomonads. Both had exceptional activity versus Haemophilus spp, Moraxella catarrhalis and Neisseria gonorrhoeae. In summary, compared to ciprofloxacin, gatifloxacin had improved activity against Gram-positive bacteria and comparable activity against Gram-negative bacteria.
Huczko
E
E
Department of Microbiology-104, Bristol-Myers Squibb Company, 5 Research Parkway, Wallingford, CT 06457, USA.
Conetta
B
B
Bonner
D
D
Valera
L
L
Stickle
T
T
Macko
A
A
Fung-Tomc
J
J
D000890:Anti-Infective Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology*; D002986:Clinical Trials as Topic; D004755:Enterobacteriaceae / Q000187:drug effects; D024841:Fluoroquinolones; D000077734:Gatifloxacin; D006801:Humans; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects*; D013296:Streptococcus pneumoniae / Q000187:drug effects*
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D002939:Ciprofloxacin; D000077734:Gatifloxacin