Acute pyelonephritis: a cause of acute renal failure?

Two patients with acute renal failure due to acute pyelonephritis are described. Examination of the renal biopsy showed normal glomeruli, severe interstitial neutrophilic infiltration and edema with no signs of acute tubular necrosis. Until now, only twelve biopsy-proven proven cases have been reported. A review of the literature on acute renal failure due to acute pyelonephritis is presented.