Also Known As
Hepatic Disease
This article was last reviewed on
This article waslast modified on
February 28, 2018.
What is the liver and what is liver disease?

The liver is a vital organ located in the upper right-hand side of the abdomen. It is as large as a football, weighs 2-3 pounds, and performs numerous functions for the body, including: metabolizing and detoxifying substances that would otherwise be harmful to the body, converting nutrients derived from food into essential blood components, regulating blood clotting, producing proteins and enzymes, maintaining hormone balances, and storing some vitamins. The liver also makes factors that help the human immune system fight infection, removes bacteria from the blood, and makes bile, which is essential for digestion.

Bile, a greenish-yellow fluid consisting of bile acids or salts and waste products such as bilirubin (which comes from breakdown of old red blood cells) and other bile pigments, flows through small bile ducts inside the liver. The bile moves from these small ducts into larger ones, like streams into a river, eventually converging into the common bile duct and exiting the liver. Some of the bile flows directly to the duodenum; the rest is stored and concentrated in the gallbladder. After a person eats, the gallbladder, a fist-sized organ that sits next to the liver, releases some of the stored bile into the small intestine, where it helps to digest fats.

Liver disease is any condition that causes liver inflammation or damage, and may affect liver function. It is categorized both by the cause and the effect it has on the liver. Causes may include infection, injury, exposure to drugs or toxic compounds, an autoimmune process, or a genetic defect that leads to the depositing and build-up of damaging substances, such as iron or copper. Effects of these injuries to the liver may include inflammation, scarring, obstructions, blood clotting abnormalities, and liver failure. The table on the next page of this article summarizes types of liver disease with links to more information about the various types.

Types of Liver Disease

Type of Liver Disease Description Examples of Causes/Conditions
Acute liver failure Rapid decrease in liver function Drugs, toxins, a variety of liver diseases
Alcoholic liver disease Liver damage due to alcohol that can lead to fatty liver disease, alcoholic hepatitis, or cirrhosis Excessive consumption of alcohol over time
Autoimmune-associated The body produces an inappropriate immune response against itself; sometimes develops antibodies against own liver tissue PBC (Primary biliary cirrhosis), PSC (Primary sclerosing cholangitis), Autoimmune hepatitis
Budd-Chiari syndrome Blood clots impede blood flow from the liver; symptoms such as ascites, enlarged liver, jaundice, and abdominal pain can develop Hypercoagulable disorders, liver injury, cancer, parasitic infection
Cirrhosis Scarring of liver tissue leads to decreased liver function Can be caused by a variety of conditions but usually a result of chronic hepatitis, alcoholism, or chronic bile duct obstruction
Genetic Gene mutations can lead to liver damage, disease; relatively rare conditions Hemochromatosis, Alpha-1 antitrypsin deficiency, Wilson disease
Hepatitis Acute or chronic liver inflammation Viruses, alcohol abuse, drugs, toxins, autoimmune, nonalcoholic fatty liver disease (NAFLD)
Infections Certain infections can cause various degrees of liver damage, blockage of bile ducts Viral hepatitis, parasitic infection
Liver cancer A cancer that originates in the liver Increased risk with cirrhosis and chronic hepatitis; hepatocellular carcinoma (HCC) is most common primary liver tumor
Obstruction of bile ducts Complete or partial blockage of bile ducts Tumors, gallstones, inflammation, trauma

 

Accordion Title
About Liver Disease
  • Signs and symptoms

    Liver disease may not cause any symptoms at first or the symptoms may be nonspecific, like weakness and loss of energy.

    In acute liver disease, symptoms related to problems processing bilirubin, including yellow skin and eyes (jaundice), dark urine, and light stools, along with loss of appetite, nausea, vomiting, and diarrhea are most common.

    Chronic liver disease symptoms may include jaundice, dark urine, abdominal swelling (due to ascites), pruritus, unexplained weight loss or gain, and abdominal pain; these symptoms are usually not present until the disease has reached an advanced stage.

  • Testing

    Laboratory Tests
    The goals with testing for liver disease are to screen for and detect liver injury, to evaluate its severity, diagnose the cause, and to monitor liver status over time. Screening and early detection are important since significant liver damage may occur with few or no symptoms. Diagnosing the cause helps health practitioners understand what type of liver disease someone has and how to treat it. The liver is often capable of repairing injuries and resolving inflammation, but conditions that cause obstruction of the bile ducts and/or lead to cirrhosis can cause permanent, progressive liver damage. Monitoring the status of a person's liver over time allows steps to be taken to preserve liver function.

    Screening, detection, and monitoring
    Several liver tests are performed routinely as part of general health screening in a comprehensive metabolic panel (CMP). Essentially the same liver tests may be ordered as a liver panel when someone has symptoms that may be due to liver injury or is at risk for developing liver disease. These tests measure the levels of specific enzymes, bilirubin, and protein that are abnormal when liver injury is present. Tests such as bilirubin may also be ordered individually to monitor a person with a liver disease. If any of the liver tests are abnormal, then they indicate the need for additional evaluation. A health practitioner will order diagnostic testing for whatever liver condition(s) a patient is suspected to have. Screening and detection tests include:

    • Alanine aminotransferase (ALT) – an enzyme found mainly in the liver; best test to detect hepatitis
    • Alkaline phosphatase (ALP) – an enzyme related to the bile ducts; often increased if ducts are blocked
    • Aspartate aminotransferase (AST) – an enzyme found in the liver and a few other places, particularly the heart and other muscles
    • Gamma-glutamyl transferase (GGT) – an enzyme found mainly in the liver; very sensitive to changes in liver function
    • Total bilirubin – measures all of the bilirubin in the blood; levels are increased with many liver diseases
    • Direct bilirubin – measures a form of bilirubin that is conjugated (combined with another compound) in the liver
    • Albumin – measures albumin, the main protein made by the liver, and tells how well the liver is making it
    • Total protein – measures albumin and all other proteins in blood, including antibodies present to help fight off infections (antibodies are not made in the liver)

    Diagnosis and monitoring
    Other tests may be ordered to help diagnose the cause of liver dysfunction. Some are used to monitor disease status and/or effectiveness of treatment. These may include:

    For more information on laboratory tests used for specific types of liver diseases, see the table on the Types page.

    Non-Laboratory Tests

    • Ultrasound
    • CT (computed tomography) scan
    • MRI (magnetic resonance imaging)
    • MRCP (magnetic resonance cholangiopancreatography)
    • PTC (percutaneous transhepatic cholangiogram)
    • ERCP (endoscopic retrograde cholangiopancreatography)

    For more information on these imaging procedures, see RadiologyInfo.org.

  • Treatment

    The most important treatment for liver disease is prevention. Vaccines are available for hepatitis A and B, and many cases of hepatitis can be prevented by avoiding the risk factors that spread the hepatitis viruses.

    Although liver inflammation due to hepatitis or other causes may resolve over time, liver damage may also become permanent. Steps to treat liver disease include protecting and supporting remaining liver function, minimizing further damage and complications, and addressing the underlying cause of the damage. Treatment may range from taking specific medications, to surgery, to – in severe cases – liver transplantation.

    People who are diagnosed with liver disease will often require long-term monitoring and should talk to their health care providers to determine the best treatment options for their condition.

Accordion Title
Types of Liver Disease
  • Acute liver failure

    Acute liver failure (ALF) is a rapid decrease in liver function. ALF can cause edema in the brain, encephalopathy, abnormal bleeding, and multiple organ failure that is often fatal. The most common cause of ALF in the U.S. is drug-related liver toxicity, such as may be seen with an acetaminophen overdose, with a variety of prescription, illicit, and herbal drugs, or with the ingestion of poisonous mushrooms or organic solvents. ALF is also sometimes seen with viral or autoimmune hepatitisnonalcoholic fatty liver disease, fatty liver that occurs during pregnancyWilson disease, and with the rapid worsening of other liver diseases.

    Tests

    Imaging scans

    • Ultrasound
    • CT (computed tomography)
    • MRI (magnetic resonance imaging)

    For more information on these imaging procedures, see RadiologyInfo.org.

  • Alcoholic liver disease

    The liver is responsible for the metabolism of alcohol. It breaks it down so that it can then be eliminated from the body. Alcohol can damage or destroy liver cells, and the liver can be seriously injured when more alcohol is consumed than it can process. Excessive consumption of alcohol is a common cause of liver damage, and alcoholic liver disease can occur after years of heavy drinking. It can lead to:

    • Fatty liver disease – this is the excessive accumulation of fat in liver cells. This condition usually produces no symptoms or mild symptoms and occurs in the earliest stages of liver disease. It will typically go away when a person stops drinking.
    • Alcoholic hepatitis – this is inflammation and swelling of the liver. It may be chronic yet mild, lasting for years but with no specific symptoms. With mild cases, the damage may be reversed if alcohol consumption is stopped. If it continues, over time, the liver may sustain more and more damage. If the damage becomes severe, the symptoms can appear quickly, within hours or days, and may be fatal.
    • Cirrhosis – this is scarring of the liver and the most serious form of alcoholic liver disease. It occurs when healthy liver tissue is replaced by hard scar tissue, affecting the structure of the liver and affecting its ability to function. The damage usually cannot be reversed but may not progress further if a person stops drinking. Cirrhosis can lead to liver failure and increases the risk of liver cancer.

    Tests
    Alcoholic liver disease is not typically tested for directly with laboratory tests. The diagnosis is often arrived at by examining the patient and getting a full medical history, especially about ingestion of alcohol. There are some tests that may be performed to help evaluate someone with liver disease due to chronic alcohol use, and certain tests may help detect chronic and/or relapse in alcohol drinking in those who deny it.

    Testing may include:

    • Gamma-glutamyl transferase (GGT) – a liver enzyme that is increased by heavy alcohol intake and also by many other conditions that affect the liver
    • Liver panel – used to detect and/or determine the extent of liver damage
    • Ethanol level – if alcohol is suspected to be a cause of liver disease
    • Carbohydrate-deficient transferrin (CDT) – can indicate relapse to heavy drinking following a period of abstinence but may be less sensitive for women and younger people

    Treatment
    There is no specific treatment for alcoholic liver disease. Usually, discontinuing the consumption of alcohol is the first step, along with avoiding other substances that can harm the liver. Many people fully recover from this type of liver disease if this is done soon enough, although it may take months for the liver to heal. Participating in a rehabilitation program or counseling may be helpful in abstaining from alcohol or treating an alcohol addiction (alcoholism). Occasionally, there is lasting damage such as cirrhosis and even liver failure. If the liver is irreversibly damaged, then a liver transplant may be an option. Transplant programs usually require someone with a history of alcohol abuse (even if alcohol may not be the underlying cause) to successfully complete a rehabilitation program before transplant can be considered as an option.

  • Autoimmune liver disease

    Autoimmune disorders are diseases caused by an inappropriate immune response against the body's own tissues. Sometimes these conditions can affect the liver.

    Autoimmune hepatitis – although the cause is not fully understood, the immune system attacks the liver and can damage it over time. Learn more about autoimmune hepatitis and associated tests.

    Primary biliary cirrhosis
    Primary biliary cirrhosis (PBC) is a chronic disease that inflames and destroys small bile ducts in the liver, impedes the flow of bile, and damages liver tissue. It is a progressive disorder that affects more women than men. The exact cause of PBC is not known, but it is thought to be an autoimmune process.

    Learn more about PBC at MayoClinic.com.

    Tests

    Primary sclerosing cholangitis
    Primary sclerosing cholangitis (PSC) is a chronic disease that is associated with inflammatory bowel disease. PSC involves the inflammation, scarring, and destruction of bile ducts, mostly those outside the liver, impedance of bile flow, and damage to liver tissue. The exact cause of PSC is not known, but it is thought to be an autoimmune process. The disorder is more common in men than women.

    Learn more about PSC at the National Digestive Diseases Information Clearinghouse web site.

    Tests

    • Liver biopsy

    Imaging scans

    • Ultrasound
    • Magnetic resonance cholangiopancreatography (MRCP)
    • Percutaneous transhepatic cholangiogram (PTC)
    • ERCP (endoscopic retrograde cholangiopancreatography)

    For more information on these imaging procedures, see RadiologyInfo.org.

  • Budd-Chiari syndrome

    Budd-Chiari syndrome is a group of symptoms that occur when one or more blood clots narrow or block the hepatic veins, those that carry blood out of the liver. This can damage the liver and the blood vessels that support it. It causes blood to accumulate in the liver, enlarging it and increasing pressure in the vein that carries blood from the digestive organs and spleen into the liver – the portal vein. This in turn can lead to fluid accumulation (edema), especially in the abdomen (ascites), dilated veins in the esophagus (varices) and abdomen, esophageal bleeding, and liver cirrhosis.

    Budd-Chiari syndrome may occur in those who have a condition that increases the risk of blood clots, such as sickle cell diseaseanti-phospholipid syndromepancreatic cancers, with blood malignancies (e.g., polycythemia vera, essential thrombocythemia), with liver or blood vessel injury, with liver cancers, and with parasitic infections. Symptoms may emerge slowly and worsen over time or develop abruptly, such as is sometimes seen as a complication of pregnancy.

    Tests

    Imaging scans

    • MRI (magnetic resonance imaging)
    • Ultrasound
    • CT (computed tomography)

    For more information on these imaging procedures, see RadiologyInfo.org.

  • Cirrhosis

    Cirrhosis is a chronic liver disease that causes advanced scarring of liver tissue. The liver can repair many injuries, but cirrhosis is usually irreversible. While it may be caused by any condition that affects the liver, in the U.S. it is commonly associated with viral hepatitis and alcoholism. Other significant causes of cirrhosis include nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, both associated with the accumulation of fat in the liver, which public health officials speculate may be linked to rising rates of obesity in the U.S.

    Cirrhosis can cause decreased liver function, chronic liver failure, bruising, bleeding, muscle wasting, ascitesgynecomastia, portal hypertension – increased blood pressure in the vein that carries blood from the digestive organs to the liver – and a number of other problems. Some people may experience severe symptoms and complications while others, with similar liver damage, will have few to moderate symptoms. Cirrhosis increases the risk of developing liver cancer.

    Tests

    For a complete list of tests, see the article on Cirrhosis.

  • Genetic liver diseases

    Genetic mutations can lead to conditions that affect the liver. These are relatively rare diseases, two of which involve the excess buildup of minerals in the body.

    • Hemochromatosis – an iron metabolism disorder that leads to excessive buildup of iron in tissues and organs. It may be genetic (inherited) or acquired and can cause organ failure, particularly of the liver, heart, and pancreas. For more information, see the article on Hemochromatosis.
    • Wilson disease – a copper metabolism disorder that leads to excessive buildup of copper in the liver. It results from an inherited genetic mutation and can cause liver, brain, and kidney damage. For more information, see the article on Wilson Disease.

    Alpha-1 antitrypsin deficiency
    Alpha-1 antitrypsin (AAT) is a protein that helps protect the lungs. It is produced in the liver at the direction of two copies of a protease inhibitor (SERPINA1) gene. If there is a change or mutation in one or both of the gene copies, then less AAT and/or dysfunctional AAT is produced. If AAT production is 30% of normal or less, then an affected person will experience alpha-1 antitrypsin deficiency and have an increased risk of developing emphysema. When AAT is dysfunctional, it tends to accumulate in the liver, forming abnormal protein chains and damaging the liver. About 10% of newborns affected with AAT deficiency are jaundiced. AAT deficiency is currently the most common genetic cause of liver disease in children.

    Tests

  • Hepatitis

    Hepatitis is an inflammation of the liver that is most frequently due to viral infections, although it can also have other causes. Find more information about the various types below:

  • Infections

    Viral hepatitis
    Liver inflammation caused by an infection with one of the five hepatitis viruses: A, B, C, D, or E. Acute hepatitis is commonly associated with the A, B, and C viruses while chronic hepatitis is only caused by B and C.

    Parasitic infection
    Relatively rare in the U.S., a variety of parasites can migrate to the liver and cause tissue damage and blockages. Examples include malaria, which can actively reproduce in liver cells, then go through a period of dormancy before causing periodic disease relapses, in addition to Ascaris lumbricoides, Chinese liver flukes (i.e., Clonorchis sinensis and Opisthorchis viverrini) which can block bile ducts, Schistosoma species (parasitic worms) which cause schistosomiasis and progressive liver scarring, and Echinococcus granulosus, which forms cysts in the liver.

    Tests

    Imaging scans

    • Ultrasound
    • X-ray
    • CT (computed tomography)
    • MRI (magnetic resonance imaging)

    For more information on these imaging procedures, see RadiologyInfo.org.

  • Liver cancer

    Cancer that originates in one part of the body but then spreads to the liver is not strictly known as "liver cancer" but rather keeps the name of its origin. For example, metastatic breast or lung cancer is still considered "breast" or "lung" cancer—and is treated accordingly—even if it spreads to the liver, because it originated in the breast or lung. "Liver cancer" means the cancer originated in the liver.

    The most common form of liver cancer in the U.S. is hepatocellular carcinoma, cancer that arises from liver cells called hepatocytes. According to the American Cancer Society, this type accounts for about 3 out of 4 cases of primary liver cancer. Another 1-2 cases out of 10 are cholangiocarcinomas, cancers that start in the bile ducts. Liver cancer is frequently asymptomaticat first, so it is not usually diagnosed in its earliest stages. Those with chronic hepatitis B and those with cirrhosis are at an increased risk of developing liver cancer. Many people with cirrhosis or advanced chronic hepatitis are regularly screened for liver cancer to detect it early, when it may be more treatable.

    Tests

    Imaging scans

    • Ultrasound
    • CT (computed tomography)
    • MRI (magnetic resonance imaging)
    • Angiography

    For more information on these imaging procedures, see RadiologyInfo.org.

  • Obstruction of bile ducts

    Gallstones, tumors, trauma, cysts, and inflammation can cause blockages or obstructions in the bile ducts. When this is severe, bile and its associated wastes accumulate in the liver, causing jaundice, dark brown urine, and pale-colored stools. The affected person may not have any symptoms initially, but if the condition persists or worsens, it can cause liver and gallbladder damage. If the duct that drains bile from the gallbladder is blocked, it can cause sharp pain to develop suddenly in the upper right part of the abdomen and may lead to fever and gallbladder infection.

    Tests

    Imaging scans

    • Ultrasound
    • CT (computed tomography)
    • Magnetic resonance cholangiopancreatography (MRCP)
    • Percutaneous transhepatic cholangiogram (PTC)
    • ERCP (endoscopic retrograde cholangiopancreatography)

    For more information on these imaging procedures, see RadiologyInfo.org.

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