[Study of cefoperazone in the field of obstetrics and gynecology. Susceptibility of clinical isolates to cefoperazone and cefoperazone concentrations in the exudate of the pelvic dead space].

As indexes for administration of cefoperazone (CPZ) in the treatment of gyneco-obstetrical infections, sensitivities to CPZ of important pathogenic organisms and CPZ concentrations in the exudate of the pelvic dead space were determined, and a pharmacokinetic analysis was made on the results. Sensitivities to CPZ were determined for freshly isolated organisms from gynecological material consisting of 227 strains of 7 aerobic bacteria and 70 strains of 1 anaerobic bacterium, in a total of 297 strains. MIC80 values of CPZ against E. coli, K. pneumoniae, P. aeruginosa, E. cloacae, C. freundii, S. aureus, S. epidermidis and B. fragilis were 0.39, 0.78, 6.25, 25, 50, 12.5, 12.5 micrograms/ml and 6.25 micrograms/ml, respectively. On the whole, these activities are relatively superior to those of other antibiotics. CPZ concentrations in the exudate of the pelvic dead space and their changes with time after 2 g single dose by drip infusion were Cmax 93.89 micrograms/ml, Tmax 1.53 hours, T 1/2 4.33 hours and AUC 759.4 hr X micrograms/ml. After 1 g single dose, they were Cmax 37.7 micrograms/ml, Tmax 3.2 hours, T 1/2 2.78 hours and AUC 339.2 hr X micrograms/ml. Similarly, after 2 g single dose intravenously, they were Cmax 111.02 micrograms/ml, Tmax 0.761 hours, T 1/2 6.22 hours and AUC 1,083.9 hr X micrograms/ml, and after 1 g single dose, they were Cmax 29.1 micrograms/ml, Tmax 2.65 hours, T 1/2 4.82 hours and AUC 296.9 hr X micrograms/ml. Similarly, after 2 g single dose intramuscularly, they were 39.4 micrograms/ml, Tmax 2.70 hours, T 1/2 8.19 hours and AUC 584.7 hr X micrograms/ml, and after 1 g single dose, they were Cmax 26.4 micrograms/ml, Tmax 5.79 hours, T 1/2 5.53 hours and AUC 435.7 hr X micrograms/ml. As indicated, there were noted dose-dependent responses and the kinetics of CPZ exudate concentrations varied with the administration routes. Whatever the dose level and the administration route were, CPZ exudate concentrations covered MIC80 values against important clinical isolates for 10 to 12 hours. This suggests that we can well expect of the antibacterial activity of this drug by any of these administration routes and dosages on the intrapelvic lesions.