We encountered a case of obstrucitve jaundice due to duodenal bile acid entrolith. A eighty year-old-woman, who had undergone gastrectomy with Billroth-II in her age of seventy one, complained of jaundice and fever. Percutaneous transhepatic cholangiography showed obstruciton of the common bile duct. Upper gastrointestinal series revealed a tumor, about 5cm in diameter, with smooth surface locating at the second portion, and a stenosis at the third portion of the duodenum. Ultrasonography revealed the tumor with stratification and acoustic shadow. The tumor was proved to be a yellow round enterolith by peroperative endoscopy. The stone was removed by duodenotomy. We recognized a diverticulum beside the Papilla Vater. Enterolith (55×46×30mm, 43g) was yellow and the section was stratified. Chemical analysis demonstrated that it consisted mainly of deoxycholic acid.
In the world and Japan one hundred twelve cases of calcium enterolith and 48 cases of bile acid enterolith have been reported. Of them genuine duodenal enterolith is rare. It seems that the production of enterolith might be caused by both existences of duodenal diverticulum and the stenosis of the afferent loop due to superior measenteric artery symdrome formed by the meander of arota.