What Is Cirrhosis of the Liver?
Cirrhosis is a serious degenerative disease that occurs when healthy cells in the liver are damaged and replaced by scar tissue, usually as a result of alcohol abuse or chronic hepatitis. As liver cells give way to tough scar tissue, the organ loses its ability to function properly. Severe damage can lead to liver failure and possibly death.
Cirrhosis poses another danger as well: Dense scarring slows the normal flow of blood through the liver, causing blood to find alternate pathways to return to the heart. This includes veins along the stomach and esophagus. The added pressure in these blood vessels, called varices, can cause them to enlarge and, in some cases, rupture. This is especially a problem for the blood vessels in the esophagus.
Every year, about 31,000 people in the U.S. die from cirrhosis, mainly due to alcoholic liver disease and chronic hepatitis C. The disease cannot be reversed or cured except, in some cases, through a liver transplant. It can often be slowed or halted, however, especially if the disease is detected in the early stages of development. Patients who think they might have cirrhosis should see a doctor without delay.
Cirrhosis is serious because of the importance of the organ it affects. The liver, weighing about three pounds and roughly the size of a football, is the largest of the body's internal organs. Among its many functions, the liver serves as an essential part of the digestive system by producing bile, which is stored in the gallbladder, then released into the small intestine, where it helps break down fatty food. The liver also helps maintain the proper composition of the blood by regulating the amounts of fat, protein, and sugar that enter the bloodstream.
As the body's primary blood filter, the liver works to detoxify alcohol, drugs, and other potentially harmful chemicals. Along with the spleen, the liver traps and disposes of worn-out red blood cells. And because it aids in the removal of bacteria and viruses from the blood, the liver is a vital component of the immune system. If your liver is not functioning properly, you are more susceptible to infection.
The liver is remarkably tolerant of disease and injury. Even after 70% of its mass has been destroyed or removed, the organ can still function, albeit with decreased effectiveness. If the conditions that caused the destruction have been removed or corrected, the liver usually can bounce back.
Although function can never be restored to parts of your liver that have turned to scar tissue, you can live a healthy life with the remaining portion if the disease is caught in time. However, there is a point of no return with cirrhosis. As more cells are replaced by scar tissue, fewer healthy cells are left to handle the liver's many tasks. Eventually, function problems arise and may remain. This is why it's important to identify the underlying causes as soon as possible and begin taking steps to eliminate them.
What Causes Cirrhosis of the Liver?
Cirrhosis occurs as the result of long-term injury to the liver. Possible causes include viruses, genetic deficiencies, prolonged obstruction of bile flow, and long periods of exposure to drugs and other toxic substances. In the majority of cases, however, the culprit is excessive consumption of alcohol.
The link between alcohol and cirrhosis is well documented. Studies show that while moderate drinking may actually help prevent strokes and heart disease, heavy drinking has a clearly harmful effect on the liver. For example, the French -- famous for their wine consumption -- have a relatively low incidence of heart disease, but the rate of cirrhosis in France is very high. Many doctors believe that more drinkers die from cirrhosis than are protected from heart disease.
Simply put, the more alcohol you drink -- and the greater the frequency of drinks -- the more likely you are to develop cirrhosis. Because the bodies of men and women process alcohol differently, the amount that you can safely imbibe depends largely on your sex. Women are more susceptible to alcohol-induced liver damage than men.
It's important to note that alcohol tolerance may vary from one person to the next. For some people, one drink per day is enough to leave permanent scars in the liver. If you drink, especially if you do so heavily and often, have a doctor examine you for signs of cirrhosis. This is necessary even if you feel healthy, since the symptoms of cirrhosis often do not appear until it is too late to stop the disease or slow its progress.
Excessive drinking almost inevitably causes some liver damage, but it does not always lead to cirrhosis. Some people who drink heavily develop alcoholic hepatitis, an inflammation of the liver that can last a week or two, producing symptoms of nausea, fever, loss of appetite, jaundice, and confusion. Over time, the condition can also lead to cirrhosis. Even light drinkers who go on a bender for several days can develop a condition known as fatty liver, caused when cells of the liver become swollen with accumulated fat and water. This condition can cause pain or tenderness in the liver and abnormalities in other liver functions. NASH (non-alcoholic steatohepatitis), a form of fatty liver disease, can also result from diabetes, elevated cholesterol, obesity, and metabolic syndrome.
Another frequent cause of cirrhosis is viral hepatitis, a general term meaning inflammation of the liver because of a viral infection. Of the various forms of this disease, only two, hepatitis B and hepatitis C, are likely to cause chronic infection which can lead to scarring and cirrhosis. Scarring usually occurs after hepatitis has become chronic (lasting six months or more). The symptoms may be so mild at first that patients with chronic hepatitis do not even realize their livers are scarring. Meanwhile, the damage continues, perhaps resulting in a serious case of cirrhosis later in life. Therefore, it is important for people with hepatitis to have regular medical checkups, especially since hepatitis can be treated and, in some cases, cured. And because hepatitis is contagious, family members of an infected person should also be tested.
Right-sided heart failure may also be a trigger of cirrhosis.
Cirrhosis sometimes, though rarely, occurs because of an inherited liver disorder. In Wilson's disease, for example, a genetic deficiency inhibits the body's ability to metabolize copper. As a result, excessive amounts of the metal accumulate in various body organs, particularly the liver, where it destroys tissue. Similarly, in hemochromatosis the body absorbs excess amounts of iron, which damages the liver and causes scarring. This disorder mostly strikes men between the ages of 40 and 60; women who have not gone through menopause are usually not affected because their bodies lose iron during menstruation. Alpha-1-antitrypsin deficiency is an enzyme deficiency that results in the accumulation of products in the liver causing destruction of liver tissue.
Children born with galactosemia lack an enzyme needed to digest a component of milk sugar. Milk sugar, also known as lactose, is composed of two sugars, glucose and galactose. The body needs to convert the galactose to glucose. In people with galactosemia, the enzyme to do this conversion is missing or not functioning adequately. Galactose accumulates in the liver at levels that become toxic and potentially fatal without proper treatment. Infants with this disorder should be taken off milk and given a substitute formula that does not contain galactose.
Some babies are born with no bile ducts, or with ducts that are malformed. Because bile is unable to drain out of the body, it accumulates in the liver and eventually poisons it. Although the problem can sometimes be corrected through surgery, most children with this disorder die from cirrhosis before they reach the age of 2.
Cirrhosis can result when strictures or scarring block the flow of bile in the bile ducts and cause it to back up into the liver for long periods of time. This occurs in conditions such as primary sclerosing cholangitis or primary biliary cirrhosis. The disease may also come as a consequence of long-term exposure to certain drugs, including methotrexate and isoniazid, and to toxic substances in the environment, such as pesticides and arsenic-based compounds. Lastly, autoimmune hepatitis is an inflammatory process in the liver that can result in scarring and cirrhosis due to antibodies produced by the body that attack the liver. The cause is unknown.