Abstract
A 35-year-old man had been treated with sulfamethizol on 6 occasions because of recurrent urinary tract infections. Furthermore, he had experienced diffuse monosymptomatic hematuria for 15 years. Cystoscopy and biopsy demonstrated irregular intestinal mucosa. Physical examination and intravenous urography were normal. Preoperative diagnosis was urachus-derived adenoma with the possibility of adenocarcinoma. At operation a typical urachus and—surprisingly—an appendico-vesical fistula were found.