gallbladders

Gallbladders are small, pear-shaped organs located beneath the liver. They store and concentrate bile, a digestive fluid produced by the liver, and release it into the small intestine as needed for fat digestion.

Bile flows from the liver through the hepatic ducts into the common bile duct. It can be diverted into the gallbladder via the cystic duct, where water and electrolytes are absorbed to concentrate the bile. When fatty nutrients enter the small intestine, the hormone cholecystokinin stimulates the gallbladder to contract and eject bile through the cystic duct and into the common bile duct toward the duodenum.

Gallstones, or cholelithiasis, are common and can form when bile becomes imbalanced in cholesterol, bile acids, or bilirubin. Risk factors include obesity, rapid weight loss, female sex, increasing age, pregnancy, and genetics. Many stones cause no symptoms, but if they block ducts they can cause biliary colic—pain in the upper abdomen or right shoulder blade—nausea, or vomiting; severe cases may lead to jaundice or pancreatitis.

Diagnosis often begins with abdominal ultrasound. Blood tests may show elevated liver enzymes or bilirubin if ducts are blocked. Additional imaging such as magnetic resonance cholangiopancreatography (MRCP) or hepatobiliary iminodiacetic acid (HIDA) scans can be used in selected cases.

Treatment depends on symptoms and complications. Asymptomatic gallstones are usually not treated. Symptomatic stones or gallbladder inflammation are commonly managed by surgical removal of the gallbladder (cholecystectomy), most often performed laparoscopically. Non-surgical options include ursodeoxycholic acid for select cholesterol stones, though recurrence is common. Complications can include cholecystitis, choledocholithiasis, and pancreatitis.