The effect of reflux on the development of pyelonephritis in urinary diversion: An experimental study

Abstract

To make an accurate comparison between ileal and colonic conduits, an ileal conduit was created from one kidney and a nonrefluxing colonic conduit from the other kidney in 16 adult mongrel dogs. The major variable between the two was the presence or absence of reflux. The dogs were studied by excretory urography, conduitograms, pressure studies, and urinary cultures. All dogs were sacrificed at 3 months, and urine cultures were collected at necropsy from conduits and both renal pelves. In each of five control experiments, one kidney was connected to either an ileal or a colonic conduit while the other kidney remained in continuity with the bladder. Although most dogs had significant bacterial growth in both conduit and ureteral urine, histologic sections revealed pyelonephritis in 83% of 12 kidneys connected to ileal conduits as compared to 7% of 14 kidneys connected to colonic conduits. All control kidneys were histologically normal. This study demonstrates that ureteral reflux from ileal conduits produces histologic evidence of pyelonephritis. Colonic conduits, by preventing reflux of infected urine, reduce the frequency of pyelonephritis and offer definite advantages for long-term urinary diversion.