A Case of Urachal Abscess Penetrating the Urinary Bladder and Sigmoid Colon

Abstract

We report a case of urachal abscess penetrating the urinary bladder and sigmoid colon. A 14-year-old boy complaining of lower abdominal pain underwent ultrasonography at a nearby clinic. A mid-lower abdominal cystic mass was detected. Abdominal enhanced CT scan showed a 90 × 67 × 46 mm abdominal mass with a thick enhanced solid wall extending from the abdominal wall and pressing against the urinary bladder to the caudal side. Antibiotic treatment effectively relieved symptoms despite growth of the abscess itself. Ultrasonography and MRI revealed penetration of the abscess into the urinary bladder and sigmoid colon, and the abscess was consequently resected. Histopathological findings demonstrated inflammatory granulation tissue penetration of both organs. Although penetration by a urachal abscess is very rare, it is important to be aware of this serious complication as it may simulate abdominal actinomycosis. Surgical treatment is essential when conservative treatment proves unsuccessful.