Primary Biliary Cirrhosis

Home

About Us

What is PBC

Areas of Support

Research

Education

Picture Gallery

PBC Videos

PBCers Store

Links

Make a Donation

Site Map

The Liver

The liver is the largest solid organ in the body, and is also the largest gland. It weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick.

 

Its normal function is essential to good health. The liver plays a major role in maintaining normal blood sugar levels, an important source of energy for the brain, heart and muscles. The liver is also responsible for manufacturing a number of proteins which comprise the building blocks of cells and tissues throughout the body. For example, serum albumin, one of the proteins produced in the liver, is the most abundant protein in the blood circulation and helps to maintain normal blood volume for the heart and vascular system. See what the liver does and how it can do so much.

 

The liver also maintains several biochemical pathways that permit the detoxification, or breakdown, of toxic products that accumulate because of the body's normal chemical functions and exposure to environmental poisons. For example, protein metabolism in the liver and other body tissues results in the production of ammonia, which is normally converted in the liver to a harmless metabolite called urea for excretion in the urine. Environmental toxins that enter the body through the lungs or digestive tract pass to the liver and are broken down through specific chemical pathways to permit excretion in the bile or urine.

 

Another important function of the liver is to manufacture bile, which plays a role in the digestion and absorption of many constituents in the normal diet. Bile, which is produced in the liver, is stored in the gall bladder, a specialized storage organ located just below the liver. The gall bladder empties bile into the intestine when food is ingested.

 

Diseases of the liver are the third most common cause of death in Americans during their most productive years and the seventh most frequent disease-related cause of death in the United States overall. Liver disease accounts for up to $8 billion yearly in economic losses. Approximately 500,000 cholecystectomies are performed each year due to gall stone disease, caused mainly by increased cholesterol secretion into bile. Alcoholic liver disease is the most common cause of liver injury in the United States. Hepatitis B and C infect approximately 5 million persons. Hepatocellular carcinoma, or liver cancer may be a consequence of these disorders and is a major interest of our physicians.

 

With the onset of liver disease, the cells of the liver, called hepatocytes are injured or die. If the injury is mild and reversible, the cells may regenerate and the patient may be left with an entirely normal liver. This remarkable capacity of the liver to regenerate is a unique feature of the organ. When the injury is more severe or sustained, regeneration may be incomplete or healing may occur with the development of fibrosis or scars, which can cause cirrhosis.

 

Physicians ordinarily make a diagnosis of cirrhosis using some form of liver biopsy, permitting the identification of marked distortion of the normal architecture of the liver by scar formation and irregular incomplete areas of regeneration. The development of cirrhosis leads to the obstruction of normal blood flow through the liver, resulting in increased pressure in the veins throughout the abdomen. A consequence for patients is the development of enlarged blood vessels or varices, in the lower end of the esophagus that can bleed and result in abnormal function of other organs and even death. When cirrhosis develops, the normal functions of the liver are disrupted, leading to raised ammonia levels that can interfere with the normal function of the brain, producing coma. Decreased albumin levels may contribute to fluid accumulation.