[Congenital cystic bile duct dilatation: an incidental intraoperative finding].

In adulthood, choledochal cysts are often surprisingly discovered during cholecystectomy. We report here on a case of an unsuspected congenital type-IA biliary cyst, according to Todani's classification encountered during laparoscopic cholecystectomy in a 30-year-old woman complaining of acute abdominal pain with an unremarkable preoperative workup. The well-known risk of developing cystic cancer, mainly in the adult, means that an excisional operation is indicated to prevent such complications. Cyst excision and Roux-en-Y hepaticojejunostomy is the definitive treatment of choice, performed at a later stage after radiological and endoscopic confirmation, and after obtaining the patient's consent. Cholangio-MR, and ERCP have proved to be extremely useful for adequate identification of this kind of lesion.