title: The in-vitro activity of mezlocillin against community hospital isolates in comparison to other penicillins and cephalosporins.
abstract: The in-vitro activity of mezlocillin was evaluated against 1795 fresh clinical isolates at a 320-bed community hospital and compared with that of ticarcillin, piperacillin, cefoxitin, cefamandole, moxalactam, cefotaxime and cefoperazone. Only 25 isolates (1.4%) were highly resistant to mezlocillin (greater than 128 mg/l). The MIC 90 values were less than or equal to 32 mg/l for all species studied, including Klebsiella, but excluding Acinetobacter and Pseudomonas where the MIC 90 values were 64 mg/l. The anti-pseudomonal activity of mezlocillin was equivalent to that of ticarcillin but less than that of piperacillin, particularly at low MIC values. Against most members of the Enterobacteriaceae mezlocillin was more active than cefoxitin or cefamandole but was less active than moxalactam, cefotaxime or cefoperazone. Its activity against enterococci exceeded that of all other agents tested, inhibiting 82% of strains at an MIC value less than or equal to 1 mg/l. Because of its exceptionally broad spectrum, mezlocillin promises to be of value for the treatment of infections due to a wide variety of micro-organisms, and particularly for mixed infections due to Gram-negative bacilli and enterococci.
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D002511:Cephalosporins / Q000494:pharmacology*; D006801:Humans; D008802:Mezlocillin / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology*
chemical_list: D002511:Cephalosporins; D010406:Penicillins; D008802:Mezlocillin