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Gallstones

Gallstones form when liquid stored in the gallbladder hardens into pieces of stone-like material. The liquid, called bile, is used to help the body digest fats. It is made in the liver (Read about "The Liver"), then stored in the gallbladder until the body needs it to digest fat. At that time, the gallbladder contracts and pushes the bile into a tube, called the common bile duct. This carries the liquid to the small intestine, where it helps with digestion.

Bile contains water, cholesterol (Read about "Cholesterol"), fats, bile salts, proteins, and bilirubin. If the liquid bile contains too much cholesterol, bile salts, or bilirubin, under certain conditions it can harden into stones.

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the two types of gallstones are cholesterol stones and pigment stones. Cholesterol stones are usually yellow-green and are made primarily of hardened cholesterol. They account for about 80 percent of gallstones. Pigment stones are small, dark stones made of bilirubin.

According to the American Gastroenterological Association, gallstone disease affects 10 to 15 percent of the population of the United States. Most are unaware of it though, because they have what are called "silent" gallstones, which produce no symptoms.

Some people though have symptomatic gallstones, which can cause pain, hospitalization and even be life threatening. A very dangerous situation occurs when gallstones block the secretions from the pancreas, triggering acute pancreatitis. (Read about "Pancreatitis") This type of gallstone requires immediate care.

The American Gastroenterological Association says the most typical symptom of gallstone disease is severe steady pain in the upper abdomen or right side, which can last for as little as 15 minutes or as long as several hours. There may also be pain between the shoulder blades or in the right shoulder, as well as vomiting or sweating.

Who's at risk

Certain people or groups are more at risk of developing gallstones. NIDDK says they include:

• women - the risk of gallstones for women between 20 and 60 years of age is twice that of men
• people over age 60
• Native Americans and Mexican Americans
• pregnant women and women using hormone therapy - excess estrogen from pregnancy or hormone use appears to increase cholesterol levels in bile and decrease gallbladder movement, both of which can lead to gallstones. (Read about "Healthy Pregnancy")
• overweight people and quick-weight-loss dieters - obesity is an important risk factor for gallstones. (Read about "Obesity") But paradoxically, NIDDK says people who lose a lot of weight rapidly are also at a great risk for developing gallstones, especially if weight loss occurs on a very low calorie diet or following gastric bypass surgery, in which the size of the stomach is reduced. It's possible that dieting shifts the balance of bile salts and cholesterol in the gallbladder, in a way that increases the risk of gallstones, according to NIDDK. It's also possible that fasting may decrease gallbladder contractions and if the gallbladder does not contract often enough to empty out the bile, gallstones may form. (Read about "Losing Weight")
• people with liver disease have a higher risk of developing gallstones (Read about "The Liver")

Symptoms & diagnosis

Symptoms of gallstones can sometimes be confused with the symptoms of other conditions. Some of the common symptoms according to NIDDK are:

• recurring intolerance of fatty foods
• colic
• belching
• gas
• indigestion (Read about "Indigestion")

Some symptoms of gallstones are often called a gallstone "attack" because they occur suddenly. A typical attack can cause:

• steady pain in the upper abdomen that increases rapidly and lasts from 30 minutes to several hours
• pain in the back between the shoulder blades
• pain under the right shoulder
• nausea or vomiting
• abdominal bloating

Gallstone attacks often follow fatty meals, and they may occur during the night. People who have the above and any of following symptoms should see a doctor right away.

• chills
• low-grade fever
• yellowish color of the skin or whites of the eyes
• clay-colored stools

When gallstones are suspected to be the cause of symptoms, the doctor is likely to do an ultrasound exam. (Read about "Ultrasound Imaging") NIDDK calls ultrasound the most sensitive and specific test for gallstones. There are other tests that can help diagnose gallstones and gallbladder problems. They can range from blood tests to CT scans and MRI's. (Read about "CT Scan - Computerized Tomography" "MRI - Magnetic Resonance Imaging")

Treatment

Silent gallstones are usually left alone and occasionally disappear on their own. Usually only patients with symptomatic gallstones are treated. According to the American Gastroenterological Association, the most common treatment for gallstones is cholecystectomy surgery to remove the gallbladder. Standard surgery, involving an incision through the abdomen, may be used. A less invasive procedure called laparoscopic (so-called "belly button" surgery) cholecystectomy may also be appropriate for some patients. If gallstones are in the bile ducts, the surgeon or gastroenterologist may use endoscopic retrograde cholangiopancreatography (ERCP) to locate and remove them before or during the gallbladder surgery. During this procedure, an endoscope - a long, flexible, lighted tube connected to a computer and TV monitor - is used. (Read about "Robotic Surgery") The doctor guides the endoscope through the stomach and into the small intestine. The doctor then injects a special dye that temporarily stains the ducts in the biliary system.

For patients who cannot undergo surgery, drugs or a procedure called lithotripsy can sometimes be used to break up or dissolve stones in the gallbladder. However, the long-term results in such cases are less predictable, according to NIDDK. Since every case is different, you should discuss all options with your doctor. (Read about "Learn About Your Procedure")

Related Information:

    Digestive System