Comparative in vitro activity of norfloxacin and four other chemotherapeutics against urinary gram-negative isolates.
Three hundred seventy-five Gram-negative bacterial strains were isolated from urine specimens of as many patients affected by symptomatic or asymptomatic urinary tract infections. Susceptibility of bacteria to five chemotherapeutics (norfloxacin, oxolinic acid, pipemidic acid, nalidixic acid and nitrofurantoin) was studied determining minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of each compound by a miniaturized dilution broth method. Norfloxacin, a quinoline carboxylic acid compound structurally related to nalidixic acid, showed a much higher antibacterial activity against all bacterial strains under examination including Pseudomonas sp. The best activity of norfloxacin was expressed either by lower MICs and lower MBCs with respect to those of the other compounds, or by a low MBC/MIC ratio, which represents an important advantage in clinical practice.
D000892:Anti-Infective Agents, Urinary / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009268:Nalidixic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D009643:Norfloxacin; D014552:Urinary Tract Infections / Q000382:microbiology*
D000892:Anti-Infective Agents, Urinary; D009268:Nalidixic Acid; D009643:Norfloxacin