hepatobiliaire

Hepatobiliary refers to the liver, the biliary tree, and related structures involved in bile production, digestion, and detoxification. The hepatobiliary system includes the liver, intrahepatic and extrahepatic bile ducts, the gallbladder, and the cystic duct, with the sphincter of Oddi regulating bile flow into the duodenum.

Anatomy and physiology: The liver, organized into lobes and lobules, contains hepatocytes that produce bile. Bile drains from the liver through intrahepatic ducts into the right and left hepatic ducts, forming the common hepatic duct. This may join with the cystic duct to create the common bile duct, which delivers bile to the duodenum. Blood supply chiefly comes from the hepatic artery and portal vein, while venous drainage occurs via hepatic veins to the inferior vena cava.

Functions: Bile emulsifies fats, aiding digestion. The liver conjugates bilirubin for elimination and metabolizes drugs and various substances. It also stores glycogen and vitamins, participates in immune responses, and synthesizes coagulation factors, contributing to overall metabolic homeostasis.

Clinical relevance: The hepatobiliary system is involved in diseases such as hepatitis (viral or autoimmune), nonalcoholic fatty liver disease, alcoholic liver disease, cirrhosis, cholestasis, bile duct strictures, gallstones causing cholelithiasis or cholecystitis, biliary atresia in infancy, and hepatobiliary cancers. Obstruction or inflammation can present with jaundice, dark urine, pale stools, itching, fatigue, and signs of liver dysfunction.

Diagnosis and treatment: Evaluation uses liver function tests and imaging like ultrasound, CT, MRI (including MRCP), and endoscopic procedures such as ERCP. Management ranges from medical therapy and lifestyle changes to surgical interventions (eg, cholecystectomy) and, in advanced disease, liver transplantation.