Serum and renal tissue concentrations of cefotaxime in urinary tract obstruction in rabbits

Serum cefotaxime and desacetylcefotaxime concentrations and their tissue concentrations in the kidney were determined at 30 minutes after cefotaxime (80 mg/kg) bolus intravenous infusion in rabbits when the urinary tract was obstructed. Serum concentration was highest in bilateral ureteral obstruction (BUO) animals (142.1 +/- 25.4 mg/L), followed in order by unilateral ureteral obstruction (UUO) animals (92.6 +/- 10.4 mg/L) and sham-operated animals (50.4 +/- 9.9 mg/L). Both serum cefotaxime and desacetylcefotaxime concentrations were highly correlated with serum creatinine levels. Conversely, the renal tissue/serum concentration ratio of cefotaxime and its metabolite was lowest in BUO animals, which was in accordance with physiological evidence that renal blood flow was reduced in BUO. Indomethacin pretreatment exaggerated cefotaxime and desacetylcefotaxime accumulation in the obstructed kidney of the UUO model, indicating that this drug inhibits renal elimination of cefotaxime when urinary tract obstruction exists.