Cirrhosis is a disease in which normal liver cells are damaged and replaced with scar tissue, disrupting liver function. It may be caused by direct injury to liver cells, or by indirect injury, such as inflammation or obstruction of the ducts that drain bile from the liver.

The liver is the largest internal organ in the body. It is located mainly in the upper right side of the abdomen, situated mostly under the lower ribs. It weighs about 3 pounds and is roughly the size of a football.

Most of the blood that leaves the stomach and intestines passes through the liver. The liver performs hundreds of functions necessary for survival, including:

• Producing blood proteins that regulate blood clotting
• Producing bile and enzymes necessary for digestion
• Metabolizing cholesterol
• Storing energy to fuel muscles
• Helping to maintain glucose (blood sugar) concentration
• Helping to regulate hormones
• Removing toxins from drugs and poisons, including alcohol

Under normal circumstances, the liver has the ability to heal itself by repairing or replacing damaged cells. With cirrhosis, the healing process is altered. Special cells, called stellate cells, increase dramatically in size and number and cause excess scar tissue to form. When scar tissue is present, it decreases the amount of normal tissue and interferes with normal blood flow through the liver which, in turn, causes liver function to deteriorate. Cirrhosis usually progresses slowly over time, but the damage done to the liver is irreversible.

Because cirrhosis impairs liver function, it can lead to many serious complications. They include:

• Portal hypertension. Blood from the intestines, spleen and pancreas enter the liver through a large blood vessel called the portal vein. When scar tissue in the liver impedes blood flow it can result in increased pressure in the vein.
  
  
• Varices. Stretched and dilated veins. When blood flow in the portal vein is blocked, it can lead to abnormally increased blood flow in nearby blood vessels, particularly in the stomach and esophagus. Because the walls of the blood vessels are thin, this can lead to bleeding. Massive bleeding in the stomach or esophagus is a life-threatening emergency that requires immediate medical treatment.
  
  
• Fluid retention. Cirrhosis can cause large amounts of fluid to accumulate in the legs (edema) or abdominal cavity (ascites). Ascites can cause discomfort and may interfere with breathing or become infected (spontaneous bacterial peritonitis).
  
  
• Bruising and bleeding. Liver damage interferes with the liver’s absorption of vitamin K and the production of proteins that help the blood clot. As a result, patients may bruise easier and bleed more frequently. Bleeding is particularly common in the gastrointestinal tract.
  
  
• Jaundice. When the liver is not able to remove bilirubin (substance formed from the breakdown of red blood cells that gives bile its color), jaundice may occur. This causes the skin and whites of the eyes to turn yellow.
  
  
• Itching. Bile salts deposited in the skin can cause itching.
  
  
• Hepatic encephalopathy Abnormal brain function that occurs when toxins from the liver enter the blood. Symptoms include forgetfulness, confusion, mood changes and, in advanced cases, delirium and coma.
  
  
• Infection. The decreased immune system function from liver damage may lead to increased bacterial infections.
  
  
• Osteoporosis Decreased bone mass and density. Cirrhosis interferes with the liver’s ability to produce vitamin D and calcium, which promote bone growth, density and health.
  
  
• Liver cancer. Cirrhosis increases the risk of developing liver cancer.
  
  
• Liver failure. This occurs when damage to the liver becomes so extensive that the liver cannot function.
  
  
• Kidney failure. Cirrhosis may cause the kidneys to function improperly or to fail (hepatorenal syndrome).