People with erythropoietic protoporphyria (EPP) are at increased risk to develop gallstones. Additionally, prolonged use of proton pump inhibitors has been shown to decrease gallbladder function, potentially leading to gallstone formation.Cholesterol modifying medications can affect gallstone formation. Statins inhibit cholesterol synthesis and there is evidence that their use may decrease the risk of getting gallstones. Fibrates increase cholesterol concentration in bile and their use has been associated with an increased risk of gallstones. Bile acid malabsorption may also be a risk. Pathophysiology
Cholesterol gallstones develop when bile contains too much cholesterol and not enough bile salts. Besides a high concentration of cholesterol, two other factors are important in causing gallstones. The first is how often and how well the gallbladder contracts; incomplete and infrequent emptying of the gallbladder may cause the bile to become overconcentrated and contribute to gallstone formation. This can be caused by high resistance to the flow of bile out of the gallbladder due to the complicated internal geometry of the cystic duct. The second factor is the presence of proteins in the liver and bile that either promote or inhibit cholesterol crystallization into gallstones. In addition, increased levels of the hormone estrogen, as a result of pregnancy or hormone therapy, or the use of combined (estrogen-containing) forms of hormonal contraception, may increase cholesterol levels in bile and also decrease gallbladder motility, resulting in gallstone formation. Composition
The composition of gallstones is affected by age, diet and ethnicity.
Gallstones within the ampulla of Vater can obstruct the exocrine system of the pancreas and can result in pancreatitis. Signs and symptoms
Gallstones, regardless of size or number, are often asymptomatic. These "silent stones" do not require treatment and can remain asymptomatic even years after they form.A characteristic symptom of a gallstone attack is the presence of colic-like pain in the upper-right side of the abdomen, often accompanied by nausea and vomiting. Pain from symptomatic gallstones may range from mild to severe and can steadily increase over a period lasting from 30 minutes to several hours. Other symptoms may include fever, as well as referred pain between the shoulder blades or below the right shoulder. If one or more gallstones block the bile ducts and cause bilirubin to leak into the bloodstream and surrounding tissue, jaundice and itching may also occur. In this case, liver enzyme levels are likely to be raised.Often, gallbladder attacks occur after eating a heavy meal. Attacks are most common in the evening or at night. Other complications
In rare cases, gallstones that cause severe inflammation can erode through the gallbladder into adherent bowel, potentially causing an obstruction termed gallstone ileus.Other complications can include ascending cholangitis, which occurs when a bacterial infection causes purulent inflammation in the biliary tree and liver, and acute pancreatitis caused by blockage of the bile ducts that prevents active enzymes from being secreted into the bowel, instead damaging the pancreas. Rarely, gallbladder cancer may occur as a complication.