[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections...

The frequency of the causative strains in urinary tract infections was investigated from the point of view of the patient's background such as age, sex administration of antibiotics and so on. Especially, the frequency of the causative strains isolated from patients within 3 days after the administration of antibiotics has markedly decreased. However, the frequency of the resistant strains such as P. aeruginosa, Enterobacter spp., Citrobacter spp. and Serratia spp. has increased after 8 days' administration of antibiotics.