The urachal (allantois) duct runs from the anterosuperior bladder to the umbilicus. Normally the duct regresses during fetal development. Persistence of all or part of the urachal duct may present with a variety of clinical findings.

Clinical Finding


umbilical discharge of urine

entire duct patent

cystic mass in the lower anterior abdominal wall in the midline

persistent midportion of the duct with both ends closed

abscess at the umbilicus or in underlying tissues, with purulent discharge

infected cyst or involvement of duct remnant that opens to the skin surface

sinus opening at the umbilicus

distal end patent but visceral end closed

diverticulum arising from the superior bladder

visceral end patent but distal end closed

umbilical or bladder mass

urachal carcinoma arising in urachal remnants


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