Comparative activities of clinafloxacin against gram-positive and -negative bacteria

Activities of clinafloxacin, ciprofloxacin, levofloxacin, sparfloxacin, trovafloxacin, piperacillin, piperacillin-tazobactam, trimethoprim-sulfamethoxazole, ceftazidime, and imipenem against 354 ciprofloxacin-susceptible and -intermediate-resistant organisms were tested by agar dilution. Clinafloxacin yielded the lowest quinolone MICs (< or = 0.5 microg/ml against ciprofloxacin-susceptible organisms and < or = 16.0 microg/ml against ciprofloxacin-intermediate-resistant organisms) compared to those of levofloxacin, trovafloxacin, and sparfloxacin. Ceftazidime, piperacillin alone or combined with tazobactam, trimethoprim-sulfamethoxazole, and imipenem usually yielded higher MICs against ciprofloxacin-resistant strains.