Rare cyst that forms in the remnants of the urachal sinus, the embryologic structure or canal between the umbilicus and bladder along the path of the umbilical cord. Failure of the urachus to completely degenerate (urachal remnant) may be due to a congenital anomaly. Typically asymptomatic unless infected. Occurs rarely in adults. Characterized by suprapubic pain and tender umbilical mass. Other signs and symptoms of infected urachal cyst may include fever, nausea, vomiting, erythema, dysuria, umbilical discharge, or acute abdomen. May be associated with other urachal abnormalities.

Management of infection includes antibiotics, drainage, and surgical excision.