AN ANALYSIS OF THE RELATIONSHIP BETWEEN BILE-DUCT STONES AND PERIAMPULLARY DUODENAL DIVERTICULA

Previous studies have suggested a relationship between bile duct stone s and periampullary duodenal diverticula. The aim of the present study was to examine this association in more detail, including step-wise l ogistic regression to identify independent predictors for the presence of diverticula. Clinical, endoscopic and radiological data were analy sed from 794 consecutive subjects with bile duct stones; 44 with prima ry duct stones (without gall-bladder stones) and 750 with bile duct st ones associated with current or previous gall-bladder stones. Frequenc ies of diverticula in subjects with bile duct stones were compared wit h those in age-matched controls who had undergone upper gastrointestin al endoscopy using a side-viewing endoscope (n = 100) or who had under gone endoscopic retrograde cholangiopancreatography (ERCP) for pancrea tic cancer (n 100). The frequencies of diverticula in subjects with pr imary duct stones (70%) and bile duct stones with current or previous gall-bladder stones (25%) were significantly higher than in both contr ol groups (7 and 8%, respectively). When subjects with bile duct stone s were analysed by step-wise logistic regression, age and bile duct di ameter were independent predictors of the presence of diverticula, but diverticula were unrelated to gender, mode of presentation, number of bile duct stones and outcome after endoscopic sphincterotomy. A signi ficant association exists between duodenal diverticula and bile duct s tones, perhaps because diverticula predispose to stone formation throu gh the combined effects of bile stasis and bacterial contamination of bile.