[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1982). III. Secular changes in susceptibility].

In vitro susceptibilities have been investigated against several species isolated from patients with simple and complicated urinary tract infections (UTI) during 1980-1982. Antimicrobial activities of the third generation cephems against E. coli isolated from patients with complicated UTI were found to decrease slightly in 1982. And those against Klebsiella spp. isolated from patients with simple and complicated UTI were also found to decrease similarly. Against P. mirabilis, all the drugs tested have showed relatively potent activities and slight changes in the susceptibility. The marked decrease of susceptibility against Citrobacter spp. isolated from UTI have been found even in the third generation cephems. Especially, Citrobacter spp. exhibited a greater degree of resistant to CZX and CPZ. Strains of P. aeruginosa were on the whole susceptible to the drugs tested, CFS, GM, TOB and AMK, inhibiting 50-80% of the strains tested at 1.56 micrograms/ml. CTX, CZX and CMX seemed most effective against S. marcescens among the third generation cephems, inhibiting 50-90% of the strains tested at 3.13 micrograms/ml.