Efficacy and safety of once daily versus intermittent dosing of tobramycin in rabbits with acute pyelonephritis.

Unilateral pyelonephritis was induced in 50 rabbits by injecting Escherichia coli (minimum inhibitory concentration of tobramycin 0.25 mg/l) into the left kidney and by obstructing the ureter temporarily. Tobramycin treatment (daily dose 10 mg/kg) was started 4 days after surgery, either in a single daily dose or in 3 divided doses at 8 h intervals, for 2, 3, 5, 7 or 10 days. Comparison of bacteriology, renal morphology, and renal functions (BUN, serum creatinine, alanine aminopeptidase, N-acetyl-beta-D-glucosaminidase, cathepsin B, sphingomyelinase) suggests better efficacy and renal tolerance of the single daily dose regimen in the treatment of experimental acute pyelonephritis.