SURVEY OF THE SENSITIVITIES OF CLINICAL ISOLATES TO ANTIBACTERIAL AGENTS (ANNUAL REPORT)

Abstract

Resarch groups were formed in 21 institutions nationwide to investigate carbapenem resistance. The activitiesof various antibacterial agents, principally carbapenems, were tested against clinical isolates collected fromthese institutions. The broth microdilution method was used to determine the minimum inhibitory concentrations (MIC) of 17 antibacterial agents for 1,241 strains of 11 bacterial species isolated at all institutions between Octoberand December 1996.
The results were as follows:
Carbapenems exhibited strong antibacterial activities against MSSA and Streptococcus pneumoniae andshowed low activities against MRSA. Their activities against Enterococcus faecalis were comparable to that ofampicillin and piperacillin.
The carbapenems showed high activities against Haemophilis influenzae, Escherichia coli, Klebsiellapneumoniae, Enterobacter cloacae, Serratia marcescens and Bacteroides fragilis group. Their activities were greater than that exhibited by other β-lactam antibacterial agents, but some resistant strains of Serratiamarcescens were detected. The antibacterial activity of carbapenems against Pseudomonas aeruginosa was comparableto that of CAZ, and there were some resistant strains.