Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1993): I. Susceptibility distribution

The frequencies of isolation and susceptibilities to antimicrobial agents were investigated on 657 bacterial strains isolated from patients with urinary tract infections in 10 hospitals during the period of June 1993 to May 1994. Of the above total bacterial isolates, Gram-positive bacteria accounted for 28.3% and a majority of them were Enterococcus faecalis. Gram-negative bacteria accounted for 71.7% and most of them were Escherichia coli. 1. Enterococcus faecalis Ampicillin (ABPC), imipenem (IPM) and vancomycin (VCM) showed the highest activities against E. faecalis isolated from patients with urinary tract infections. The MIC₉₀s of them were 2 µg/ml. Piperacillin (PIPC) was also active with the MIC₉₀ of 8 µg/ml. The others were not so active with the MIC₉₀s of 32 µg/ml or above. 2. Staphylococcus aureus including MRSA VCM showed the highest activities against S. aureus isolated from patients with urinary tract infections. Its MIC₉₀ was 1 µg/ml. Arbekacin (ABK) was also active with the MIC₉₀ of 2 µg/ml. The others were not so active with the MIC₉₀s of 32 µg/ml or above. 3. Staphylococcus epidermidis VCM showed the strongest activity against S. epidermidis isolated from patients with urinary tract infections. Its MIC₉₀ was 1 µg/ml. ABK was also active with the MIC₉₀ of 4 µg/ml. The others except ABPC were not so active with the MIC₉₀s of 32 µg/ml or above. 4. Streptococcus agalactiae Most of the agents were active against S. agalactiae isolated from patients with urinary tract infections. Penicillins, cephems, erythromycin (EM), and clindamycin (CLDM) showed the highest activities. The MIC₉₀s of them were 0.25 µg/ml or below. Amikacin (AMK) and minocycline (MINO) showed somewhat low activities with the MIC₉₀s of 16 µg/ml. 5. Citrobacter freundii IPM showed the highest activities against C. freundii isolated from patients with urinary tract infections. Its MIC₉₀ was 2 µg/ml. Cefozopran (CZOP) and gentamicin (GM) were also active with the MIC₉₀s of 8 µg/ml. Penicillins and cephems generally were not so active. 6. Enterobacter cloacae IPM and GM showed the highest activities against E. cloacae. The MIC₉₀s of them were 1 µg/ml. CZOP and tosufloxacin (TFLX) were also active with the MIC₉₀s of 8 µg/ml. Penicillins and cephems except CZOP showed lower activities with the MIC₉₀s of 64 µg/ml or above. 7. Escherichia coli Most of antimicrobial agents were active against E. coli. Flomoxef (FMOX), CZOP, IPM, CPFX and TFLX showed the highest activities against E. coli. The MIC₉₀s of them were 0.125 µg/ml or below. Cefmenoxime (CMX), ceftazidime (CAZ), cefuzonam (CZON), latamoxef (LMOX), carumonam (CRMN), norfloxacin (NFLX) and ofloxacin (OFLX) were also active with the MIC₉₀s of 0.25 µg/ml. Penicillins and MINO were not so active with the MIC₉₀s of 32 µg/ml or above. 8. Klebsiella pneumoniae CZOP, IPM and CRMN showed the highest activities against K. pneumoniae. The MIC₉₀s of them were 0.125 µg/ml or below. CAZ, CZON, CFIX, CPFX and TFLX were also active the MIC₉₀s of 0.25 µg/ml. Penicillins were not so active with the MIC₉₀s of 128 µg/ml or above. 9. Proteus mirabilis P. mirabilis was susceptible to a majority of drugs. CMX, CAZ, CZON, LMOX, CFIX, CRMN and CPFX showed the highest activities against P. mirabilis isolated from patients with urinary tract infections. The MIC₉₀s of them were 0.125 µg/ml or below. MINO was not so active with the MIC₉₀ of 256 µg/ml or above. 10. Pseudomonas aeruginosa Most of the agents were not so active against P. aeruginosa. IPM showed MIC₉₀ of 8 µg/ml. The others were not so active with the MIC₉₀s of 32 µg/ml or above. IPM and CPFX showed MIC₅₀s of 1 µg/ml. TOB showed MIC₅₀ of 2 µg/ml. 11. Serratia marcescens Most of the agents were not so active against S. marcescens. All agents showed MIC₉₀s of 32 µg/ml or above. IPM showed MIC₅₀ of 2 µg/ml, CRMN and GM showed MIC₅₀s of 4 µg/ml, respectively.