cefoxitin and cefminox

We studied the in vitro activity of cefminox (MIC by agar dilution) and cefoxitin against 477 facultative Gram-positive and Gram-negative isolates which were recovered from clinical specimens and identified by standard methods. Cefminox has proved to be 4-16 times more active than cefoxitin against enteric Gram-negative bacilli commonly involved in cholecystitis, secondary peritonitis, intraabdominal abscesses and gynecological infections. On the contrary, cefoxitin has proved to be four times more active against Gram-positive cocci. Both have been ineffective against Enterobacter spp., Pseudomonas aeruginosa and Acinetobacter spp. The microbiological activity and pharmacokinetic parameters of cefminox make it one of the first choice treatments for community-acquired intraabdominal and pelvic infections with the presence of anaerobes.

Topics: Bacterial Infections; Cefoxitin; Cephamycins; Humans

The susceptibility of the new cephamycin antibiotic, cefminox, to hydrolysis by various types of beta-lactamase produced by organisms of the Bacteroides fragilis group was compared with that of cefoxitin. Several enzymes were able to achieve complete hydrolysis of both drugs during overnight incubation, but no marked difference between the rates of inactivation of cefminox and cefoxitin was observed. Susceptibility of the cephamycins to crude extracts of beta-lactamases from the test strains of Bacteroides spp. did not correlate with the results of conventional minimum inhibitory concentration titrations. Possible reasons for these discrepancies are discussed.

Topics: Bacteroides fragilis; beta-Lactamases; Cefoxitin; Cephamycins; Chromatography, High Pressure Liquid; Kinetics; Microbial Sensitivity Tests