False-positive ultrasonography in agenesis of the gallbladder: a pitfall in the laparoscopic cholecystectomy approach.

We report a case of agenesis of the gallbladder in a 15-year-old girl incorrectly diagnosed as cholelithiasis on preoperative sonography and suspected at laparoscopic surgery. The diagnosis of agenesis was confirmed at open surgery with intraoperative sonography, intraoperative cholangiography, and postoperative radioisotope scan. Difficulties in preoperative diagnosis and the management during laparoscopic and open surgery are discussed.