A gallstone is a solid crystal deposit that forms in the gallbladder, which is a pear-shaped organ that stores bile salts untilthey are needed to help digest fatty foods. Gallstones can migrate to other parts of the digestive tract and cause severepain with life-threatening complications.
in size and chemical structure.
A gallstone may
be as tiny
as a grain
or as large
as a golf ball.Eighty percent
of gallstones are composed
of cholesterol. They are formed when the liver produces more cholesterol thandigestive juices can liquefy. The remaining 20%
of gallstones are composed
of calcium and
an orange-yellow wasteproduct called bilirubin. Bilirubin gives urine its characteristic color and sometimes causes jaundice
Gallstones are the most common of all gallbladder problems. They are responsible for 90% of gallbladder and bile ductdisease, and are the fifth most common reason for hospitalization of adults in the United States. Gallstones usuallydevelop in adults between the ages of 20 and 50; about 20% of patients with gallstones are over 40. The risk ofdeveloping gallstones increases with age-at least 20% of people over 60 have a single large stone or as many as severalthousand smaller ones. The gender ratio of gallstone patients changes with age. Young women are between two and sixtimes more likely to develop gallstones than men in the same age group. In patients over 50, the condition affects menand women with equal frequency. Native Americans develop gallstones more often than any other segment of thepopulation; Mexican-Americans have the second-highest incidence of this disease.
Gallstones can cause several different disorders. Cholelithiasis is defined as the presence of gallstones within thegallbladder itself. Choledocholithiasis is the presence of gallstones within the common bile duct that leads into the firstportion of the small intestine (the duodenum). The stones in the duct may have been formed inside it or carried there fromthe gallbladder. These gallstones prevent bile from flowing into the duodenum. Ten percent of patients with gallstoneshave choledocholithiasis, which is sometimes called common-duct stones. Patients who don’t develop infection usuallyrecover completely from this disorder.
is a disorder marked
of the gallbladder.
It is usually caused
by the passage
of a stone fromthe gallbladder into the cystic duct, which
is a tube that connects the gallbladder
to the common bile duct.
ofcases, however, cholecystitis develops
in the absence
of gallstones. This form
of the disorder
is called acalculouscholecystitis. Cholecystitis causes painful enlargement
of the gallbladder and
is responsible for 10-25%
of all gallbladdersurgery. Chronic cholecystitis
is most common
in the elderly. The acute form
is most likely
in middle-aged adults.
Cholesterolosis or cholesterol polyps is characterized by deposits of cholesterol crystals in the lining of the gallbladder.This condition may be caused by high levels of cholesterol or inadequate quantities of bile salts, and is usually treated bysurgery.
, which results from
a gallstone’s blocking the entrance
to the large intestine,
is most common
in elderlypeople. Surgery usually cures this condition.
Narrowing (stricture) of the common bile duct develops in as many as 5% of patients whose gallbladders have beensurgically removed. This condition is characterized by inability to digest fatty foods and by abdominal pain, whichsometimes occurs in spasms. Patients with stricture of the common bile duct are likely to recover after appropriatesurgical treatment.
Causes and symptoms
Gallstones are caused by an alteration in the chemical composition of bile. Bile is a digestive fluid that helps the bodyabsorb fat. Gallstones tend to run in families. In addition, high levels of estrogen, insulin, or cholesterol can increase aperson’s risk of developing them.
or the use
of birth control pills can slow down gallbladder activity and increase the risk
So candiabetes, pancreatitis
, and celiac disease
. Other factors influencing gallstone formation are:
- intestinal disorders
- coronary artery disease or other recent illness
- multiple pregnancies
- a high-fat, low-fiber diet
- heavy drinking
- rapid weight loss
Gallbladder attacks usually follow a meal of rich, high-fat foods. The attacks often occur in the middle of the night,sometimes waking the patient with intense pain that ends in a visit to the emergency room. The pain of a gallbladderattack begins in the abdomen and may radiate to the chest, back, or the area between the shoulders. Other symptoms ofgallstones include:
- inability to digest fatty foods
- low-grade fever
- chills and sweating
- nausea and vomiting
- clay-colored bowel movements
by a family doctor,
in digestive problems
or a specialist
ininternal medicine. The doctor will first examine the patient’s skin for signs
of jaundice and feel (palpate) the abdomen forsoreness
or swelling. After the basic physical examination
, the doctor will order blood counts
or blood chemistry tests
of bile duct obstruction and
to rule out other illnesses that cause fever and pain, including stomachulcers, appendicitis
, and heart attacks.
More sophisticated procedures used to diagnose gallstones include:
- Ultrasound imaging. Ultrasound has an accuracy rate of 96%.
- Cholecystography (cholecystogram, gallbladder series, gallbladder x ray). This type of study shows how thegallbladder contracts after the patient has eaten a high-fat meal.
- Fluoroscopy. This imaging technique allows the doctor to distinguish between jaundice caused by pancreatic cancerand jaundice caused by gallbladder or bile duct disorders.
Gallstones form in the gallbladder but can migrate to other parts of the body via the bileduct.
(Illustration by Argosy Inc.)
- Endoscopy (ERCP). ERCP uses a special dye to outline the pancreatic and common bile ducts and locate the positionof the gallstones.
- Radioisotopic scan. This technique reveals blockage of the cystic duct.
One-third of all patients with gallstones never experience a second attack. For this reason many doctors advise watchfulwaiting after the first episode. Reducing the amount of fat in the diet or following a sensible plan of gradual weight lossmay be the only treatments required for occasional mild attacks. A patient diagnosed with gallstones may be able tomanage more troublesome episodes by:
- applying heat to the affected area
- resting and taking occasional sips of water
- using non-prescription forms of acetaminophen (Tylenol or Anacin-3)
A doctor should be notified if pain intensifies or lasts for more than three hours; if the patient’s fever rises above 101 °F(38.3 °C); or if the skin or whites of the eyes turn yellow.
of the gallbladder
) is the most common conventional treatment for recurrent attacks.Laparoscopic surgery, the technique most widely used,
is a safe, effective procedure that involves less pain and
a shorterrecovery period than traditional open surgery.
In this technique, the doctor makes
a small cut (incision)
in the patient’sabdomen and removes the gallbladder through
a long tube called
. Shock wave therapy
) uses high-frequency sound waves
up the gallstones. Thepatient can then take bile salts
to dissolve the fragments. Bile salt tablets are sometimes prescribed without lithotripsy
todissolve stones composed
by raising the level
of bile acids
in the gallbladder. This approach requires long-term treatment, since
it may take months
or years for this method
a sizeable stone.
CONTACT DISSOLUTION. Contact dissolution can destroy gallstones in a matter of hours. This minimally invasiveprocedure involves using a tube (catheter) inserted into the abdomen to inject medication directly into the gallbladder.
Alternative therapies, like non-surgical treatments, may provide temporary relief
of gallstone symptoms. Alternativeapproaches
to the symptoms
of gallbladder disorders include homeopathy, Chinese traditional herbal medicine, and acupuncture
. Dietary changes may also help relieve the symptoms
of gallstones. Since gallstones seem
to develop moreoften
in people who are obese, eating
a balanced diet, exercising, and losing weight may help keep gallstones fromforming.
Forty percent of all patients with gallstones have “silent gallstones” that produce no symptoms. Silent stones, discoveredonly when their presence is indicated by tests performed to diagnose other symptoms, do not require treatment.
Gallstone problems that require treatment can
be surgically corrected. Although most patients recover, some developinfections that must
be treated with antibiotics
In rare instances, severe inflammation can cause the gallbladder to burst. The resulting infection can be fatal.
The best way
to prevent gallstones
is to minimize risk factors.
a 1998 study suggests that vigorous exercise may lower
a man’s risk
of developing gallstones
by as much
as 28%. The researchers have not yet determined whetherphysical activity benefits women
to the same extent.
— A reddish-yellow waste product produced
by the liver that colors urine and
in the formation
to digest wheat protein (gluten), which causes weight loss, lack
of energy, and pale, foul-smelling stools.
— Cholesterol crystals
in the lining
of the gallbladder.
Common bile duct
— The passage through which bile travels from the cystic duct
to the small intestine.
of the large intestine caused
by a gallstone that has blocked the intestinal opening.
— A nonsurgical technique for removing gallstones
by breaking them apart with high-frequency sound waves.
National Digestive Diseases Clearinghouse (NDDIC). 2 Information Way.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Building 31, Room 9A04, 31 Center Drive,MSC 2560, Bethesda, MD 208792-2560. (301) 496-3583. http://www.niddk.nih.gov.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.