Structure and Composition of Common Bile Duct Stones in Relation to Duodenal Diverticula, Gastric Resection, Cholecystectomy and Infection

Abstract

Background: Common bile duct stones represent a clinical problem often involving severe infection, cholangitis and cholestasis. Stasis and infection are thought to play a part in the pathogenesis of choledocholithiasis. Investigations on the etiology of common bile duct stones are, however, scarce because of the difficult access to common bile duct stones and bile. In a clinical series of common bile duct stones, we studied the gross appearance of stones extracted endoscopically from the common bile duct and measured the cholesterol and bilirubinate content in order to elucidate factors of importance to etiology. Methods: In 135 patients treated endoscopically for bile duct stones, the stones or parts of the stones were collected. Appearances of the cut surface of the stones were studied and described. Cholesterol and bilirubinate content were analyzed enzymatically and with infrared spectroscopy. The growth in bile of gas-producing bacteria previously shown to be correlated with enterobacteriacea was investigated. Results: Seventy-five percent of the stones were pigment stones, the majority with concentric pigmented layering. There was good agreement between cholesterol measurements. With a cutoff at 50% for the infrared measurements and 25% for the enzymatic assay only 3 stones were discordant between cholesterol measurements and visual inspection. Twenty-one of 23 patients with a previous Billroth-II gastric resection had pigment stones (p < 0.05). Gas-producing bacteria were significantly more prevalent in the bile from patients with layered pigment stones. Conclusion: Pigment stones with concentric layering highly suggestive of a cyclic process of crystallization were recovered from the common bile duct in 70% of the patients in our series.

Comparison of the composition of bile acids in bile of patients with adenocarcinoma of the pancreas and benign disease

“…Research conducted on CBD stones may offer an explanation. CBD stones prevent the flow of bile into the duodenum, leading to bile stasis which has been shown to cause bacterial growth [22] . As with a CBD stone, a tumour at the head of the pancreas can also cause bile duct obstruction.…”

Importance of Bile Composition for Diagnosis of Biliary Obstructions

“…The patients with diagnosed choledocholithiasis have shown elevated primary/secondary (P/S) ratios compared to pancreatic neoplasms and elevated conjugated/unconjugated (C/U) ratios of BSs when compared to benign strictures as shown in Figure 3 B,C. Blockage resulting from the gallstone formation inhibits the flow of the BSs from the gallbladder to the small intestine leading to dysbiosis and, therefore, a reduction in BSH [ 58 , 59 , 60 ]. Depletion of BSH leads to suppression of the deconjugation process.…”

“…Therefore, an alteration in the conjugation level and an obstruction-induced reduction of BS concentration in the small intestine may change the BS synthesis via action of FXR and promote excessive BA synthesis. Imbalance in the BA composition can be caused by a number of factors, e.g., 1. altered synthesis due to FXR promotion or inhibition [ 47 , 56 ]; 2. change in the function of BAAT; 3. change in the function of the BA transporters [ 57 ]; 4. change in the external concentration of the BS due to a blockage [ 58 , 59 , 60 ]; 5. changed function of BSH [ 58 , 59 , 60 ].…”

Bile Acids and Microbiota Interplay in Pancreatic Cancer

“…Another alternative explanation stems from the research on common bile duct stones. Sandstad et al showed that stones in the common bile duct could obstruct the bile flow into the duodenum, resulting in bile stasis associated with the growth of bacteria [107]. In addition, bile duct obstruction can also result from pancreatic head tumours [102].…”