Critical appraisal of air pouch infection model in rats

The aim of this study was to assess the efficacy and pharmacokinetic profiles of gentamicin, vancomycin, and levofloxacin in a rat air pouch model, in which Staphylococcus aureus (ATCC 25293) was used as the test organism. Antibiotic treatments (i.p.) were started 1 hour after bacterial inoculation and continued for 5 days. Bacterial counts and antibiotic concentrations were determined in pouch exudates that were obtained on the 5th day of antibiotic treatment. The following observations were made: 1) The concentrations of gentamicin or vancomycin in the exudate were found to be below the detection limit. 2) Levofloxacin and ciprofloxacin exhibited a dose-dependent effect on bacterial counts in the exudate. 3) The antibacterial efficacy of levofloxacin was found to be enhanced when the total daily dose of 10 mg was divided into smaller parts. The present study also showed that the air pouch infection model was a valuable tool to assess the pharmacokinetic and pharmacodynamic properties of antibiotics.