In vitro antimicrobial activity of gatifloxacin against 873 clinical isolates from respiratory tract, urinary tract and surgical infections during 1997-1998 in Japan.

The in vitro activity of gatifloxacin was determined for 873 isolates from various infections during 1997-1998 in Japan. Gatifloxacin was active against streptococci, Escherichia coli, Klebsiella pneumoniae, Moraxella catarrhalis, Haemophilus influenzae and Neisseria gonorrhoeae, with MIC(90)s of </=0.39 mg/L. The activity was two- to 32-fold greater than that of ciprofloxacin and levofloxacin against Gram-positive bacteria, and comparable to that against Gram-negative bacteria. Gatifloxacin was more active than the other quinolones against quinolone-resistant staphylococci, Enterococcus faecalis, E. coli and Enterobacter cloacae. It also had good activity against penicillin- or macrolide-resistant Streptococcus pneumoniae and ampicillin-resistant H. influenzae.