The gallbladder is an organ that is largely ignored and poorly understood by many, that is until it starts acting up. Individuals can have their gallbladder removed without any major health consequences – much like the appendix. However, it has an important and specific role in proper digestion. It is a sac-shaped organ that lies beneath the liver in the right, upper quadrant of the abdomen that is about three inches long and two inches wide. Its main function is to store and concentrate bile.
Bile is mostly water, but it contains bile acids, bile salts, and cholesterol that are necessary for fat absorption in the intestines. Bile is made in the liver and is then transported via the bile duct to the gallbladder. The gallbladder then removes unnecessary water and solutes from the bile, concentrating it down to less than five times the volume produced in the liver. When a food source containing fat enters the stomach, hormones are released that tell the gallbladder to release bile. It contracts and sends the bile through ducts into the duodenum. The bile helps to digest and absorb the fat so the body can use it.
The two most common diseases seen in regard to the gallbladder are gallstones (cholelithiasis) and infection (cholecystitis). As many as 20 million Americans have gallstones and about a million more will develop them each year.
Gallstones are mainly composed of cholesterol. Since the gallbladder’s job is to concentrate bile, it can become “supersaturated” and precipitate within the gallbladder to begin the formation of stones. Only about a third of individuals with gallstones will ever have symptoms. It’s usually the smaller stones that can get into the duct system causing blockage and pain. This is what is commonly called a “gallbladder attack.” It occurs most often when the individual has eaten a fatty meal. Persistent or chronic intermittent blockage of the duct by stones can also lead to the development of infection.
Gallstones are about three times more common in women than men. This may be related to the female sex hormones’ effect on cholesterol. Other risk factors include age over forty, obesity, rapid weight loss, diabetes, and some medications.
Diagnosis of gallstones is based on the doctor’s evaluation of the individual’s symptoms (pain in the right upper abdomen, nausea, vomiting and bloating) and physical findings. Lab tests may indicate infection and/or elevations in the liver tests. Ultrasound is the most useful imaging test to look for stones in the gallbladder. It can also see some stones in the major ducts that may be blocking the passage and thickening of the gallbladder wall due to acute or chronic inflammation.
Individuals with infection or severe pain due to gallstones usually end up having the gallbladder and stones removed surgically (cholecystectomy) – about 500,000 patients per year. Nowadays, this surgery is often performed laparoscopically, that is, using a scope through small incisions in the abdomen. Asymptomatic individuals may be able to control the condition through dietary alterations and medications under the care of their physician.
The content in this column is for informational purposes only. Consult your physician for appropriate individual treatment. Dr. Reynolds practices Family Medicine in Chesterfield.