ANTIMICROBIAL ACTIVITY OF CEFTAZIDIME AND AZTREONAM IN URINE

Abstract

We investigated serum and urinary concentrations of ceftazidime and azthreonam in three healthy male volunteers after a single 1.0g intravenous administration, and evaluated their antimicrobial activity in urine against clinical isolates of three Pseudomonas aeruginosa with different MICs, Serratia marcescens and Escherichia coli.The peak serum level of ceftazidime was 94.2μg/ml (HPLC) and that of aztreonam was 103.4μg/ml (HPLC).
The cumulative urinary recovery rate of ceftazidime at 12 hours after intravenous administration was 90.6%(HPLC) and that of aztreonam was 65.1%(HPLC).
Antimicrobial activity of ceftazidime and aztreonam in urine was calculated by the dilution ratio. That of ceftazidime was higher against two of the three isolates of P. aeruginosa, but against S. marcescens and E. coli there was only a slight difference.