What are gallstones?
Gallstones are small, pebble-like substances that develop in the gallbladder. The gallbladder is a small, pear-shaped sac located below your liver in the right upper abdomen. Gallstones form when liquid stored in the gallbladder hardens into pieces of stone-like material. The liquid—called bile—helps the body digest fats. Bile is made in the liver, then stored in the gallbladder until the body needs it. The gallbladder contracts and pushes the bile into a tube—called the common bile duct—that carries it to the small intestine, where it helps with digestion.
What causes gallstones?
Scientists believe cholesterol stones form when bile contains too much cholesterol, too much bilirubin, or not enough bile salts, or when the gallbladder does not empty completely or often enough. The reason these imbalances occur is not known.
The cause of pigment stones is not fully understood. The stones tend to develop in people who have liver cirrhosis, biliary tract infections, or hereditary blood disorders—such as sickle cell anemia—in which the liver makes too much bilirubin.
The mere presence of gallstones may cause more gallstones to develop. Other factors that contribute to the formation of gallstones, particularly cholesterol stones, include
* Sex. Women are twice as likely as men to develop gallstones. Excess estrogen from pregnancy, hormone replacement therapy, and birth control pills appears to increase cholesterol levels in bile and decrease gallbladder movement, which can lead to gallstones.
* Family history. Gallstones often run in families, pointing to a possible genetic link.
* Weight. A large clinical study showed that being even moderately overweight increases the risk for developing gallstones. The most likely reason is that the amount of bile salts in bile is reduced, resulting in more cholesterol. Increased cholesterol reduces gallbladder emptying. Obesity is a major risk factor for gallstones, especially in women.
* Diet. Diets high in fat and cholesterol and low in fiber increase the risk of gallstones due to increased cholesterol in the bile and reduced gallbladder emptying.
* Rapid weight loss. As the body metabolizes fat during prolonged fasting and rapid weight loss—such as “crash diets”—the liver secretes extra cholesterol into bile, which can cause gallstones. In addition, the gallbladder does not empty properly.
* Age. People older than age 60 are more likely to develop gallstones than younger people. As people age, the body tends to secrete more cholesterol into bile.
* Ethnicity. American Indians have a genetic predisposition to secrete high levels of cholesterol in bile. In fact, they have the highest rate of gallstones in the United States. The majority of American Indian men have gallstones by age 60. Among the Pima Indians of Arizona, 70 percent of women have gallstones by age 30. Mexican American men and women of all ages also have high rates of gallstones.
* Cholesterol-lowering drugs. Drugs that lower cholesterol levels in the blood actually increase the amount of cholesterol secreted into bile. In turn, the risk of gallstones increases.
* Diabetes. People with diabetes generally have high levels of fatty acids called triglycerides. These fatty acids may increase the risk of gallstones.
How are gallstones treated?
Surgery
If you have gallstones without symptoms, you do not require treatment. If you are having frequent gallbladder attacks, your doctor will likely recommend you have your gallbladder removed—an operation called a cholecystectomy. Surgery to remove the gallbladder—a nonessential organ—is one of the most common surgeries performed on adults in the United States.
Nearly all cholecystectomies are performed with laparoscopy. After giving you medication to sedate you, the surgeon makes several tiny incisions in the abdomen and inserts a laparoscope and a miniature video camera. The camera sends a magnified image from inside the body to a video monitor, giving the surgeon a close-up view of the organs and tissues. While watching the monitor, the surgeon uses the instruments to carefully separate the gallbladder from the liver, bile ducts, and other structures. Then the surgeon cuts the cystic duct and removes the gallbladder through one of the small incisions.
Recovery after laparoscopic surgery usually involves only one night in the hospital, and normal activity can be resumed after a few days at home. Because the abdominal muscles are not cut during laparoscopic surgery, patients have less pain and fewer complications than after “open” surgery, which requires a 5- to 8-inch incision across the abdomen.
If tests show the gallbladder has severe inflammation, infection, or scarring from other operations, the surgeon may perform open surgery to remove the gallbladder. In some cases, open surgery is planned; however, sometimes these problems are discovered during the laparoscopy and the surgeon must make a larger incision. Recovery from open surgery usually requires 3 to 5 days in the hospital and several weeks at home. Open surgery is necessary in about 5 percent of gallbladder operations.
The most common complication in gallbladder surgery is injury to the bile ducts. An injured common bile duct can leak bile and cause a painful and potentially dangerous infection. Mild injuries can sometimes be treated nonsurgically. Major injury, however, is more serious and requires additional surgery.
If gallstones are present in the bile ducts, the physician—usually a gastroenterologist—may use ERCP to locate and remove them before or during gallbladder surgery. Occasionally, a person who has had a cholecystectomy is diagnosed with a gallstone in the bile ducts weeks, months, or even years after the surgery. The ERCP procedure is usually successful in removing the stone in these cases.
Nonsurgical Treatment
Nonsurgical approaches are used only in special situations—such as when a patient has a serious medical condition preventing surgery—and only for cholesterol stones. Stones commonly recur within 5 years in patients treated nonsurgically.
* Oral dissolution therapy. Drugs made from bile acid are used to dissolve gallstones. The drugs ursodiol (Actigall) and chenodiol (Chenix) work best for small cholesterol stones. Months or years of treatment may be necessary before all the stones dissolve. Both drugs may cause mild diarrhea, and chenodiol may temporarily raise levels of blood cholesterol and the liver enzyme transaminase.
* Contact dissolution therapy. This experimental procedure involves injecting a drug directly into the gallbladder to dissolve cholesterol stones. The drug—methyl tert-butyl ether—can dissolve some stones in 1 to 3 days, but it causes irritation and some complications have been reported. The procedure is being tested in symptomatic patients with small stones
