Management of stones in the biliary tree.

Stones in the biliary tree may coexist with gall-bladder stones, may be found only in the common duct (in the absence of gall-bladder stones) or, more rarely, may be present in the intrahepatic biliary tree-as in the Caroli syndrome.1 One of the most frequent causes of choledocholithiasis, however, is the retained common duct stone which has been left behind inadvertently after elective or emergency cholecystectomy. Despite the routine use of intraoperative cholangiography, exploration of the common duct (where indicated) at the time of cholecystectomy and even, on occasions, the use of fibre optic choledochoscopy, there is still a 1-4% incidence of retained common duct stones after cholecystectomy.2 When stones are discovered in the biliary tree, there are several therapeutic options-including, in selected patients, the use of oral chenodeoxycholic (CDCA) or ursodeoxycholic (UDCA) acid, the gallstone dissolving agents which are more commonly used in the treatment of cholesterol-rich stones in the gall bladder.3 Elsewhere in this issue Dr Gianfranco Salvioli and his colleagues from Modena in Italy describe the results of a random allocation, double masked trial in 28 patients with uncomplicated biliary stones, half of whom were treated with 12 mg UDCA/kg/day in three divided doses, while the other half received placebo. Seventeen of these patients had stones in the gall bladder while four had a radiologically normal gall bladder with stones only in the biliary tree. Although the end point of the study was intended to be 24 months, only four of the 28 patients actually completed the two year trial-either because the stones had disappeared completely before that time, or because the patients developed biliary colic, pain or cholangitis, underwent surgery or simply 'dropped out'. None of the 14 patients given placebo showed evidence of gallstone dissolution, but seven of the 14 UDCA-treated patients showed complete disappearance of the stones, as judged by normal intravenous cholangiograms, after six, 12, or 18 months' treatment-while one showed partial gall stone dissolution (defined as at least a 25% reduction in stone diameter or the disappearance of one or more stones). If one arbitrarily classifies 'drop-outs' as treatment failures, then the complication rate, whether because of the stones or of the treatment, was higher in the placebo treated patients (12 out of 14) than in the UDCA-treated group (six out of 14). The reason for the 'drop-outs' in three of the 14 patients given UDCA is not stated. These patients may simply …