A 3-year-old girl is brought to your clinic because she has had three urinary tract infections and foul smelling drainage from her umbilicus. On exam you fell a firm mass between the umbilicus and the symphysis pubis. An ultrasound has shown this mass to be solid, so you order a CAT scan.

The scan shows contrast within the bladder (bright white area). However, there is a filling defect (gray area) on the anterior dome of the bladder. This is a urachal abscess.

The mass was surgically excised. This photo was taken from inferior looking cephalad. The base of the bladder would be at the bottom of the picture and the umbilicus would be at the top. Here you see that the dome of the bladder has a small opening that communicates with a large urachal abscess. After the urachal abscess was removed, the girl had no more urine infections.

Adenocarcinomas occasionally develop in a persistent urachus.