University of Iowa Health Science Relations and
Jeffrey Field, MD
Professor of Internal Medicine
First Published: 2000
Last Revised: September 2004
Peer Review Status: Internally Peer Reviewed

About 500 thousand persons in the United States will require removal of the gallbladder this year, and many aren't sure why this most common of major operations is necessary.

Dr. Jeffrey Field, professor of internal medicine at the UI Carver College of Medicine explains, "Almost all the problems result when stones are formed in the gallbladder and block the tiny tube through which the gallbladder fills and empties."

Between meals the gallbladder normally collects and stores bile that has been manufactured in the liver. When the nervous and hormonal systems signal the presence of food, the gallbladder contracts, emptying the bile into the intestine to aid the digestion of fats.

When the tube is blocked, however, normal emptying is impaired, and stagnant conditions in the gallbladder allow growth of bacteria.

The more common type of gallstones consists predominately of cholesterol, the same fatty substance that causes problems in arteries. The cholesterol in bile is kept in solution by the detergent action of bile acids and phospholipids.

Gallstones originate when the concentration of bile cholesterol rises and results in the precipitation of cholesterol crystals.

Symptoms of acute gallbladder disease include severe pain in the upper right abdomen, nausea and vomiting, fever and chills. Chronic gallbladder problems show up as discomfort or pain, particularly after fatty meals. X-rays or ultrasound may show stones in the gallbladder.

Dr. Field explains that some persons are more likely than others to develop gallbladder disease:

• Heredity may play a part. For example, the Pima Indians have a higher incidence of gallstones and gallbladder disease.
• Women are almost four times as likely as men to require the operation. Furthermore, taking oral contraceptives for several years seems to add to the risk of gallstones.
• Obese persons and others with high blood cholesterol levels are more likely to be affected.
• Patients with diseases of the small bowel may have more trouble because the bile salts may not be adequately reabsorbed and recycled into the liver. This loss of bile salts decreases the ability of the body to keep the cholesterol from precipitating and forming gallstones.