Urachal anomalies: acquired patent urachus and giant urachal cyst--2 cases report.

Two cases of rare urachal anomalies in the adult are described, including one acquired patent urachus and one giant urachal cyst. The presenting symptoms and signs included pyuria, fever, lower abdominal pain and palpable abdominal mass. The correct preoperative diagnosis was made after sonography. The clinical and radiographic features and magnetic resonance imaging are presented. Stone formation and the huge capacity of the urachal cyst are first reported. Excision of the urachal tract with resection of the bladder dome and cauterization of the cystic wall with stone removal were performed in that order. When a young adult presenting with a wet umbilicus, acute abdominal pain or a lower midline abdominal mass, the possibility of an infected urachal anomaly should be considered in the differential diagnosis.