With advanced endoscopic and laparoscopic techniques being readily accessible to the treating surgeon, determining the wisest path to the successful treatment of choledocholithiasis and cholangitis has become more challenging. Nevertheless, a large number of options allow one to tailor-specific therapy to each individual clinical situation so as to achieve the highest probability of success. In this chapter we attempt to give the reader a better understanding of the methods available for the diagnosis and treatment of common bile duct (CBD) stones and cholangitis so that treatment plans are developed that are patient-specific and have the highest chance of success.
Classification and Epidemiology
A common entity in Western societies, gallstones are found in approximately 15% of Americans and result in 700,000 cholecystectomies a year. The annual cost of medical care for gallstones is almost $6.5 billion (1.3% of US health care costs) compared with chronic liver disease and cirrhosis ($1.6 billion), chronic hepatitis C ($0.8 billion), and diseases of the pancreas ($2.2 billion).1 CBD (downstream of the confluence of the hepatic ducts) stones have been noted in 10–15% of patients with cholelithiasis, and this incidence increases with age to over 80% in those who are over 90 years old.2 Choledocholithiasis in Western countries usually results from stones originating in the gallbladder and migrating through the cystic duct. These secondary bile duct stones are cholesterol stones in 75% and black pigment stones in 25% of patients. Cholesterol stones are formed in the presence of cholesterol saturation, biliary stasis, and nucleating factors. Behavioral factors associated with cholesterol gallstones include nutrition, obesity, weight loss, and physical activity. Biologic factors linked to gallstones include increasing age, female sex and parity, serum lipid levels, and the Native American, Chilean, and Hispanic race.1 The formation of black pigment stones is associated with hemolytic disorders, cirrhosis, ileal resection, prolonged fasting, and total parenteral nutrition.2
Primary bile duct stones, on the other hand, form within the bile ducts and usually are of the brown pigment variety. These tend to be lower in cholesterol content and higher in bilirubin content as compared with secondary stones. Unlike secondary stones, primary stones are associated with biliary stasis and bacteria.3 In fact, in the pathogenesis of brown pigment stones, bile infection appears to be the initial event leading to stone formation.4 Moreover, bacteria have been found in brown pigment stones by electron microscopy but not in black pigment stones. Primary bile duct stones are more common in Asian populations, and these often are associated with primary intrahepatic stones in this population.1 These intrahepatic stones usually are calcium bilirubinate and mixed stones and contain more cholesterol and less bilirubin than the extrahepatic bile duct pigmented stones. The pathogenesis of these intrahepatic stones appears to involve bile infection; biliary stasis; low-protein, low-fat diets and malnutrition; and parasitic infections. However, the role of Ascaris lumbricoides and Clonorchis sinensis in the formation of intrahepatic stones ...