Gallstones are hard, pebble-like deposits that form inside the gallbladder. Gallstones may be as small as a grain of sand or as large as a golf ball, depending on how long they have been forming.

The cause of gallstones varies. Some stones form when there is too much cholesterol or bilirubin in the bile. (Bile is a liquid that helps the body digest fats.) Other stones form if there are not enough bile salts or if the gallbladder fails to empty properly.

One type of gallstones, called pigment stones, tend to occur in people who have medical conditions that cause the liver to make too much bilirubin. Pigment stones are also more common in persons with liver cirrhosis and biliary tract infections.

Gallstones are a common health problem worldwide. They are more common in women, Native Americans, and people over the age of 40.

Other risk factors include ethnic and hereditary factors, obesity, diabetes, liver cirrhosis, long-term intravenous nutrition, and some operations for peptic ulcers.

Gallstones often have no symptoms and are usually discovered by a routine x-ray, surgery, or autopsy.

Symptoms usually start after a large stone blocks the cystic duct or the common bile duct. The cystic duct drains the gallbladder, and the common bile duct is the main duct draining into the duodenum. Together, these ducts form part of the biliary system.

A stone blocking the opening from the gallbladder or cystic duct usually produces symptoms of biliary colic, which is cramping pain in the middle to right upper abdomen. If the stone does not pass into the duodenum, but continues to block the cystic duct, acute cholecystitis results.

If the common bile duct is blocked for a long period of time, bacteria may grow behind the stone in the stagnant bile, producing symptoms of cholangitis. Cholangitis is a serious condition and usually requires hospitalization. Continued blockage of normal bile flow may produce jaundice (yellow skin and eyes).

Stones blocking the lower end of the common bile duct (where it enters the duodenum) may obstruct secretion from the pancreas, producing pancreatitis. This condition can also be serious and may require hospitalization.

In general, pay attention to the following symptoms:

• Abdominal pain in the right upper abdomen or in the middle of the upper abdomen, which:
  • May be recurrent
  • May be sharp, cramping, or dull
  • May radiate to the back or below the right shoulder blade
  • May be made worse by fatty or greasy foods
  • Occurs within minutes of a meal
• Jaundice
• Fever

Additional symptoms that may be associated with this disease include:

• Clay-colored stools
• Nausea and vomiting
• Heartburn
• Excess gas
• Abdominal indigestion
• Abdominal fullness

It is important to see a doctor if you have symptoms of gallstones. Gallstones are present in many people with gallbladder cancer.

There are numerous tests to detect the presence of gallstones or gallbladder inflammation:

• Abdominal ultrasound
• Abdominal CT scan
• Abdominal x-ray
• Oral cholecystogram
• Gallbladder radionuclide scan
• Endoscopic retrograde cholangiopancreatography (ERCP)

This disease may also alter the results of the following tests:

• Fecal fat
• Urine bilirubin
• Abdominal MRI