Comparative activities of five antimicrobial agents in experimental Proteus pyelonephritis in mice.

Five antimicrobial agents, ciprofloxacin, ticarcillin, piperacillin, aztreonam and gentamicin, were compared both in vitro (MIC's, time-kill studies) and in vivo, in the treatment of experimental Proteus mirabilis pyelonephritis in mice. In the treatment of the pyelonephritis, ciprofloxacin was clearly superior to the other agents, both with respect to the percentage of sterile kidneys after treatment as with respect to the mean numbers of bacteria per kidney. The results can only be partially explained by the in vitro activities of the different antibiotics.