Cholecystitis is inflammation of the gall bladder. Symptoms include right upper abdominal pain, nausea, vomiting, and occasionally fever. Often gallbladder attacks (biliary colic) precede acute cholecystitis. The pain lasts longer in cholecystitis than in a typical gallbladder attack. Without appropriate treatment, recurrent episodes of cholecystitis are common. Complications of acute cholecystitis include gallstone pancreatitis, common bile duct stones, or inflammation of the common bile duct.

More than 90% of the time acute cholecystitis is from blockage of the cystic duct by a gallstone. Risk factors for gallstones include birth control pills, pregnancy, a family history of gallstones, obesity, diabetes, liver disease, or rapid weight loss. Occasionally acute cholecystitis occurs as a result of vasculitis, chemotherapy, or during recovery from major trauma or burns. Cholecystitis is suspected based on symptoms and laboratory testing. Abdominal ultrasound is then typically used to confirm the diagnosis.

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