Cholecystitis is an inflammation of the gallbladder, which is a small organ located on the right side of the abdomen, just beneath the liver. The gallbladder stores and concentrates bile, a fluid produced by the liver to help digest fats. Gallstones, infections, and blockages are the most common causes of cholecystitis.
Gallstones are the most common risk factor for cholecystitis. Gallstones are hard deposits of bile that form in the gallbladder. They can range in size from a grain of sand to a golf ball. Gallstones may form when there is an imbalance in the substances that make up bile, such as cholesterol, bilirubin, and bile salts. The stones can block the flow of bile out of the gallbladder, leading to inflammation.
Infections are another risk factor for cholecystitis. Infections of the gallbladder may be caused by bacteria, such as E. coli, or by viruses. These infections can cause inflammation of the gallbladder, leading to cholecystitis.
Blockages of the bile ducts, which carry bile from the liver to the gallbladder and from the gallbladder to the small intestine, can also cause cholecystitis. Blockages can be caused by gallstones, by inflammation of the ducts, or by tumors.
Other risk factors for cholecystitis include obesity, diabetes, and certain medications, such as steroids and certain cholesterol-lowering drugs. People over the age of 60 are also at higher risk of developing cholecystitis.