Gallstones are deposits of hardened digestive fluid that form in the gallbladder, according to Mayo Clinic. Gallstones range in size and can be accompanied by a number of symptoms, such as pain in the abdomen, fever and jaundice, which is a yellowing of the skin. There are two different types of gallstones: cholesterol gallstones and pigment gallstones. Gallstones can form due to several different causes.
Cholesterol in Bile
When too much cholesterol is present in bile, cholesterol gallstones can form. Normally, the liver excretes just the proper amount of cholesterol that can successfully be dissolved by the chemicals contained in the bile. When too much cholesterol is excreted, it cannot be properly dissolved by the bile and the concentration of cholesterol retained in the bile increases. This can happen as a result of conditions such as obesity or diabetes. In less common cases, cholesterol saturation can occur as a result of a decrease in bile salt secretion or lecithin secretion, according to The Merck Manuals Online Medical Library. A decrease in bile salt secretion usually occurs as a result of the disease cystic fibrosis. Lecithin secretion occurs as a result of a rare genetic disorder.
Bilirubin in Bile
Bilirubin is a chemical that is produced as a byproduct of the breakdown of red blood cells, according to Mayo Clinic. The accumulation of bilirubin in the bile can result from different circumstances. In the first condition, there may be an increase in the production of bilirubin due to an increase in hemolysis, or the breaking apart of red blood cells. An increase in hemolysis can be caused by infections, medications, immune system responses or toxins, according to Medline Plus. Another condition that can cause the accumulation of bilirubin in the bile is the inability of the liver to properly remove bilirubin from the body. This can be caused by bile duct blockage, an inherited disorder or liver diseases such as cirrhosis or hepatitis, according to Lab Tests Online. Too much bilirubin in the bile causes pigment gallstones.
Biliary Dyskinesia
Biliary dyskinesia is the improper or inadequate emptying of the gallbladder. If bile is not emptied properly from the gallbladder, it can accumulate and become extremely concentrated, which can lead to the formation of gallstones. Biliary dyskinesia usually occurs as a result of muscle defects in the gallbladder, which hinder the natural movement of the muscle required to fully empty the gallbladder, according to the University of Maryland Medical Center.
