A colo-urachal-cutaneous fistula in an 88-year-old male

Urachus anomalies are remnants of the urachus, an embryonic connection between the fetal bladder and umbilicus. These anomalies usually remain asymptomatic but can cause symptoms in case of infection. An extremely rare complication of symptomatic urachal remnants is fistulizing to adjacant viscera. We describe the first case of diverticulitis associated sigmoid-urachal-cutaneous fistula.

An 88-year-old male visited the outpatient clinic with intermittent bleeding and gassy discharge from his umbilicus. Examination showed a normal looking umbilicus with a small fissure at the bottom in which a 10 cm probe could be inserted. Laparotomy revealed a fistula extending from the umbilicus to a pus filled cyst superior to the bladder. A second fistula between the cyst and a mid-sigmoid diverticulum was identified. The involved sigmoid segment was resected. Pathological examination demonstrated no malignancy.

Urachal remnants are extremely rare in adults. They typically present with abdominal pain or palpable masses. Additional imaging can aid the diagnostic process.

Due to the risk of recurrence and malignant transformation complete surgical excision of urachal anomalies is the treatment of choice. This can be done in a 1-step or 2-step procedure.