[Therapeutic efficacy of cefodizime in combination with aminoglycosides against systemic infections caused by Pseudomonas aeruginosa in immunocompromised tumour bearing mice].

In vivo synergistic effects of cefodizime (CDZM) were investigated in combination with aminoglycosides (AGs), sisomicin (SISO) or dibekacin (DKB) against Pseudomonas aeruginosa in immunocompromised tumour bearing mice. Fractional effective dose (FED) indices showed that either synergistic or additive effects were observed between CDZM and AGs. The synergistic intraperitoneal bactericidal effect of CDZM in combination with SISO or DKB was also observed in immunocompromised tumour bearing mice. The post antibiotic effect (PAE) of AGs was prolonged by the addition of CDZM. Moreover, the strong synergistic bactericidal effects of CDZM and AGs against P. aeruginosa were observed in the presence of immunocompromised tumour bearing murine polymorphonuclear leukocytes (PMN). These results suggest that the strong therapeutic efficacy of CDZM in combination with AGs was caused by synergistic bactericidal effect of CDZM and AGs in the presence of PMN.