Gallstones

Gallstones are solid deposits that form from components of bile, most often within the gallbladder. The two major categories are cholesterol stones and pigment stones, which differ in composition and in the conditions that favor their formation. Many gallstones remain in the gallbladder without causing symptoms .¹

Stone formation occurs when bile becomes favorable for crystal formation and those crystals are retained long enough to grow. Cholesterol stones commonly involve cholesterol supersaturation, nucleation of crystals, and impaired gallbladder emptying. Pigment stones contain larger proportions of calcium bilirubinate and are linked to different biological settings. A stone becomes clinically important mainly when it obstructs bile flow or contributes to inflammation, infection, or pancreatitis .¹

Gallstones are not the same as gallbladder inflammation. Cholelithiasis means the presence of stones, whereas acute cholecystitis is inflammation of the gallbladder, usually after obstruction of the cystic duct by a stone. Stones can also move into the common bile duct, a condition called choledocholithiasis. These distinctions matter because the location of a stone and whether it obstructs a duct determine the physiological consequences .¹