Tubular urachal remnants in adult bladders.

We studied the structure and histologic appearance of intramural tubular urachal remnants in bladders from an unselected series of 122 autopsies, in which the patient age at death was 38 to 91 years. The bladders were fixed with formaldehyde introduced 10 minutes to 5 hours post mortem. Of the bladders 32 per cent showed tubular urachal remnants. The remnants were classified into 3 types on the basis of the epithelial extent and structure. Of the remnants 68.4 per cent had lumen covered with transitional epithelium, while the remainder had columnar epithelium. Bud-like epithelial proliferations were found in 43.6 per cent and mild dysplasia of the epithelium was found in 7.7 per cent of the urachal remnants, while mild inflammation in the loose peritubular tissue was demonstrated in 23.1 per cent.