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Cirrhosis
is the irreversible replacement of a large amount of normal liver
tissue with nonfunctioning scar tissue. It develops because the
liver is damaged. Attempts at regenerating new liver cells are not
effective.
Liver damage, when repeated or sustained, can result in cirrhosis. In the United States, the most common cause of cirrhosis is alcoholism—continued excessive intake of alcohol for a long time. Viral hepatitis is a common cause: chronic hepatitis C in developed countries, and chronic hepatitis B in many parts of Asia and Africa. Fatty liver (nonalcoholic steatohepatitis) and other metabolic problems such as iron overload (hemochromatosis) can also cause cirrhosis.
Cirrhosis is the third most common cause of death after heart disorders and cancer among people aged 45 to 65. The scar tissue forms bands throughout the liver, destroying the liver's internal structure and impairing the liver's ability to regenerate itself or function. The liver is less able to do the following:
The scar tissue also blocks blood flow through the portal vein (which carries blood from the intestines to the liver). The result is high blood pressure in that vein (portal hypertension—see Manifestations of Liver Disease: Portal Hypertension). In addition, the scar tissue can block the flow of bile (a greenish yellow digestive fluid produced by the liver) out of the liver.
Symptoms
Many people with mild cirrhosis have no symptoms and appear to be well for years. About one third never develop symptoms. Others are weak, feel sick and fatigued, have a poor appetite, and lose weight. The tips of the fingers may enlarge (called clubbing). If the flow of bile is chronically blocked, people develop jaundice (see Manifestations of Liver Disease: Jaundice), overall itchiness, and small yellow skin bumps (nodules), especially around the eyelids. Because the damaged liver cannot produce enough bile salts, absorption of fats and fat-soluble vitamins (A, D, E, and K) is impaired. As a result, people may feel weak, have stools that are greasy and foul-smelling (steatorrhea), and lose their appetite. Undernutrition and weight loss commonly result from the impaired absorption of fats and vitamins and from loss of appetite.
People with cirrhosis may have other symptoms due to severe liver failure or alcoholism:
Complications:
Advanced cirrhosis causes additional problems. The high blood pressure in the portal veins can cause dilated, twisted veins to form at the lower end of the esophagus (esophageal varices—see Manifestations of Liver Disease: Portal Hypertension), in the stomach (gastric varices), or in the rectum (rectal varices). People may vomit large amounts of blood if the esophageal or gastric varices bleed. High blood pressure in the portal vein plus impaired liver function may lead to fluid accumulation in the abdomen (ascites—see Manifestations of Liver Disease: Ascites). Kidney failure may develop, and brain function may deteriorate (causing hepatic encephalopathy—see Manifestations of Liver Disease: Hepatic Encephalopathy).
Because vitamin D is poorly absorbed with impaired bile excretion, osteoporosis can develop. Because vitamin K is poorly absorbed, people have a tendency to bleed easily. The spleen, if enlarged, may trap blood cells and platelets, preventing them from entering the bloodstream. Platelets (important for blood clotting) in the blood decrease, making the tendency to bleed worse. Bleeding into the gastrointestinal tract will result in anemia.
Liver cancer (hepatocellular carcinoma or hepatoma) can develop, particularly when cirrhosis is due to chronic hepatitis B or hepatitis C or alcoholism.
Diagnosis
Cirrhosis is usually diagnosed based on symptoms, results of the physical examination, and a history of risk factors such as alcoholism. During the physical examination, a doctor may feel a small, firm liver. Occasionally, the doctor feels small lumps (nodules) on the surface of the liver or an enlarged spleen.
Blood tests to evaluate liver function are done. Results are often normal because these tests are relatively insensitive and the liver has a tremendous reserve. The liver can carry out essential functions even when its total activity is 85% below normal. A complete blood cell count (CBC) is done to check for anemia and other blood abnormalities. Blood tests may be done to check for hepatitis and other possible causes. Ultrasonography or computed tomography (CT) can determine whether the liver is shrunken or abnormally patterned, suggesting cirrhosis. Radionuclide scanning (using a radioactive isotope) can show which areas of the liver are functioning and which are scarred. If the diagnosis is still uncertain, a liver biopsy (removal of a tissue sample for examination under a microscope) is done to confirm it. Biopsy and sometimes blood tests can also help doctors determine the cause of cirrhosis.
If cirrhosis is confirmed, screening tests for liver cancer should be done every 6 to 12 months. Tests include blood tests to measure alpha-fetoprotein levels and ultrasonography. Levels of alpha-fetoprotein (a protein normally produced by immature liver cells in fetuses) increase when liver cancer develops.
Prognosis and
Treatment
Cirrhosis is usually progressive. Stopping all alcohol intake halts further liver scarring but cannot reverse damage already done. Continued alcohol use, even small amounts, leads to progressive disease and serious complications. Once a major complication occurs—such as vomiting of blood, accumulation of fluid in the abdominal cavity, or deterioration in brain function—the outlook is grim.
No cure exists for cirrhosis. The liver will never again be normal. Cirrhosis is best arrested at its earliest stages to stop any further injury. Treatment includes eliminating the cause (such as alcohol) and treating complications as they develop. People need to inform their doctor of all the drugs they are taking, including over-the-counter drugs and dietary supplements, because the damaged liver may not be able to metabolize them. If people need to take drugs that are metabolized by the liver, much smaller doses are used to avoid further damage to the liver. In those with advanced cirrhosis, the diet should be limited in protein and sodium, and supplemental vitamins should be taken.
Liver transplantation can be lifesaving for people with advanced cirrhosis. If they continue to drink too much alcohol or if another cause cannot be altered, a transplanted liver also eventually develops cirrhosis. Thus, liver transplantation is not done unless the person has abstained from alcohol for at least 6 months.
Last full review/revision September 2007 by Eldon A. Shaffer, MD
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