[Sensitivity of the recent bacterial isolates to cefotaxime and other cephem antibiotics]

Antimicrobial susceptibility of 703 nonselected strains of 14 different bacterial species to cefazolin, cefmetazole, cefotiam, cefoperazone latamoxef, and cefotaxime (CTX) was examined. CTX was the most active against E. coli, Klebsiella, Serratia, P. mirabilis, H. influenzae, beta-Streptococcus group A, beta-Streptococcus group B and S. pneumoniae. On the other hand, CTX-resistant (MIC greater than or equal to 50 micrograms/ml) strains were isolated at the following frequencies: Citrobacter, 21.7%; Enterobacter, 7.7%; Serratia, 4.6%; P. aeruginosa, 40.4% and B. fragilis, 28.6%. Of the 411 strains classified as very sensitive () or moderately sensitive (++) by disk method, 405 strains (98.5%) were inhibited by less than or equal to 12.5 micrograms/ml of CTX. Only 1 strain (0.2%) was falsely classified as moderately sensitive and no strains were falsely categorized as resistant.