Stone Analysis Health Article

Gallbladder stones

Approximately 80% of gallbladder stones are primarily cholesterol (over 70% cholesterol by weight). They also contain bile pigments, bile acids, fatty acids, and calcium salts. The remainder of gall stones are primarily made of bilirubin. The primary constituents are calcium bilirubinate, calcium phosphate, and calcium carbonate. A gallbladder stone is also called a cholelith (cholerefers to the gallbladder and -lith means stone). Cholesterol-rich gallbladder stones typically develop when the following three conditions exist:

• supersaturation of gallbladder, due mainly to increased biliary cholesterol secretion
• abnormally rapid precipitation of micro-crystals of cholesterol due to an excess of promoters and/or a shortage of inhibitors of crystallization
• stasis within the gallbladder due to the combination of impaired motility, primarily reduced emptying in response to food and/or crystal trapping by an abnormally thick mucus glycoprotein on the gallbladder lining

Many people do not realize that they have stones in their gallbladders. These stones are small enough to allow the liver, gallbladder, and pancreas to continue functioning normally, never causing any pain. Gallbladder stones cause problems when they interfere with the normal flow of bile. They can obstruct the flow down the common bile duct that carries bile from the gallbladder to the small intestine. Gall stones may obstruct the pancreatic duct, the tube that connects the pancreas with the common bile duct. This can cause inflammation of the pancreas (pancreatitis). The pancreas and gall bladder do not normally experience any back pressure. When pressure builds from backed-up bile (gall bladder) or pancreatic secretions (pancreas), swelling will occur. If the pancreas is subjected to this pressure for some time, it may cause damage to the internal structures of the organ. When the gallbladder is subjected to pressure, it simply enlarges and exerts pressure on the liver. When a gallbladder stone is lodged at the end of the common bile duct (in the Sphincter of Oddi where it opens into the small intestine), the backed-up bile may also cause all of the structures (liver, gallbladder, pancreas and ducts) to swell. Because the ducts have muscle tissue in their walls, the presence of a stone will make them spasm, causing pain.

About 12% of men and 25% of all women will develop gallstones in their lifetimes. Gallbladder stones are most common among:

• Caucasians
• females
• women who have had children
• people over the age of 40
• people who previously have had gallbladder stones
• people who are overweight