Prevalence and radiologic and histologic appearance of vesicourachal diverticula in dogs without clinical signs of urinary tract disease

Abstract

To determine prevalence and radiologic and histologic appearance of vesicourachal diverticula in dogs without clinical signs of urinary tract disease. Original study. 50 dogs between 4 months and 17 years old representing 22 breeds that had been euthanatized for unrelated reasons; none of the dogs had a history or clinical signs of urinary tract disease. Retrograde positive-contrast radiography was performed, and radiographs were examined for macroscopic diverticula. Necropsy specimens from the urinary bladder vertex were examined by means of light microscopy for diverticula and signs of inflammation. 17 of the 50 (34%) dogs had vesicourachal diverticula, and 1 additional dog had a urachal cyst. Fifteen of the 17 diverticula were macroscopic; surface area of the diverticulum could be measured radiographically in 13 of these dogs and ranged from 1 to 90 mm2. The remaining 2 diverticula were microscopic. Sixteen diverticula were intramural and 1 was extramural. Light microscopic signs of bladder wall inflammation could be detected in 5 dogs, 4 of which had macroscopic diverticula. Results suggest that a high percentage of dogs without clinical signs of urinary tract disease may have vesicourachal [corrected] diverticula. Further studies are needed to determine the clinical relevance of vesicourethral diverticula in dogs.