Gallstones are formed within the gallbladder, an organ that stores bile excreted from the liver. Bile is a solution of water, salts, lecithin, cholesterol, and other substances. If the concentration of these components changes, they may precipitate from solution and form gallstones.
Gallstones may be as small as a grain of sand, or they may become as large as an inch in diameter, depending on how much time has elapsed from their initial formation.
Causes, incidence, and risk factors
Gallstones often have no symptoms and are usually discovered incidentally by a routine x-ray, surgery, or autopsy.
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 (total parenteral nutrition), and certain operations for peptic ulcers.
Symptoms usually start after a stone of sufficient size (larger than 8mm) 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. Collectively, 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 right upper quadrant abdominal pain that feels like cramping. 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 substantial period of time, bacteria may find their way up behind the stone and grow 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.
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 quadrant or in the middle of the upper abdomen, which: o May be recurrent o May be sharp, cramping, or dull o May radiate to the back or below the right shoulder blade o May be made worse by fatty or greasy foods o Occurs within minutes of a meal
Additional symptoms that may be associated with this disease include:
- Clay-colored stools
- Nausea and vomiting
- Gas or excessive flatus
- Abdominal indigestion
- Abdominal fullness, gaseous
Signs and tests
There are numerous tests to detect the presence of gallstones or gallbladder inflammation:
- Abdominal ultrasound
- Abdominal CT scan
- Abdominal x-ray
- Oral cholecystogram
- Gall bladder radionuclide scan
- ERCP (endoscopic retrograde cholangiopancreatography)
This disease may also alter the results of the following tests:
- Fecal fat quantitation
- Urine bilirubin
- Abdominal MRI
Modern advances in surgery have revolutionized the treatment of gallstones. In general, surgery is used only if you have symptoms.
In the past, open cholecystectomy (gallbladder removal) was the usual procedure for uncomplicated cases. This operation required a medium to large incision just below the right lower rib in order to access the gallbladder. After this operation, a patient typically spent 3-5 days in the hospital recovering.
However, a minimally-invasive technique called laparoscopic cholecystectomy was introduced in the 1980s which uses small incisions and camera guidance to remove the gallbladder.
Currently, laparoscopic cholecystectomy is the gold standard for treating gallstones that cause symptoms and is one of the most common operations performed in hospitals today. Using this approach, a patient may have their gallbladder removed in the morning and be discharged from the hospital on the same evening or the next morning.
In addition, gallstones blocking the common bile duct may be visualized and removed during the laparoscopic procedure. Because this surgical treatment method has a complication rate of less than 1%, it has supplanted using medication to treat gallstones.
In people with a functioning gallbladder, bile salts taken by mouth may dissolve gallstones. However, the process may take 2 years or longer, and stones may return after the therapy is ended.
Medical dissolution, using both high-dose and low-dose chenodeoxycholic acids (CDCA, chenediol) was an approach investigated in the early 1980s. However, it was successful in only 14% of cases and required a long period of administration and a lifetime of maintenance therapy.
Urodeoxycholic acid (UDCA, ursodiol) is successful in only 40% of cases. Both CDCA and UDCA therapies are useful only for gallstones formed from cholesterol.
Other chemical methods include contact dissolution, in which a catheter is passed through the abdominal wall and into the gallbladder. Methyl tert-butyl ether, a volatile chemical, is then instilled. This chemical rapidly dissolves cholesterol stones, but potential toxicity, stone recurrence, and other complications limit its usefulness.
Electrohydraulic shock wave lithotripsy (ESWL) has also been used to treat gallstones. In this method, electromagnetic high-energy shock waves break up the stones.
This approach was particularly popular in the mid to late 1980s, when some studies found it to clear gallstones in up to 60% of patients. However, its application is limited if there are a large number of stones present, if the stones are very large, or in the presence of acute cholecystitis or cholangitis. It can also be used in association with UDCA to improve its effect.
Gallstones develop in many people without causing symptoms. The chance of symptoms or complications from gallstones is about 20%. With current surgical approaches, the outlook is excellent for people with symptoms - over 99% of patients have no recurrence of symptoms.
- Cholecystitis - acute
- Cholecystitis - chonic
Calling your health care provider
Call for an appointment with your health care provider if you have pain in the right upper quadrant of your abdomen, jaundice, or other symptoms of gallstones.
There is no known way to prevent gallstones. If you have gallstone symptoms, eating a low fat diet and losing weight may help control symptoms.
by Sharon M. Smith, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.