In Vitro Activity of Mezlocillin and Its Related Compounds Against Aerobic and Anaerobic Bacteria

A total of 900 clinical isolates of aerobic (462 isolates) and anaerobic (438 isolates) bacteria were tested against mezlocillin in comparison with other penicillins, and the aerobes were also tested against cephalothin, cefoxitin, and cefamandole. Among penicillins, mezlocillin was the most effective against Escherichia coli, Klebsiella pneumoniae, Salmonella species, Pseudomonas aeruginosa , and Bacteroides fragilis . Mezlocillin was more effective than cephalothin against Klebsiella pneumoniae .