Histopathological studies of kidney and bladder after ileovesical diversion in dogs

The histopathological changes in bladder and kidneys after diversion of the contents of the small intestine to the urinary bladder were studied in 8 mongrel dogs, 6 to 48 months postoperatively. The bladder showed a moderate inflammatory reaction, a slight hyperplasia of the epithelium, and a slight to moderate submucosal fibrosis. These changes did not seem to grow worse with increasing observation time. These results indicated that there were no major risks for progressive bladder contraction. Renal pelvises showed mild chronic inflammation and slight fibrous thickening of the wall. Localized pyelonephritic scarring was observed in one out of 10 kidneys, the other 9 being normal.