Find information on medical topics, symptoms, drugs, procedures, news and more, written in everyday language.

* This is the Consumer Version. *

Fibrosis of the Liver

by Jesse M. Civan, MD

Fibrosis is the formation of an abnormally large amount of scar tissue in the liver. It occurs when the liver attempts to repair and replace damaged cells.

  • Many conditions can damage the liver.

  • Fibrosis itself causes no symptoms, but severe scarring can result in cirrhosis, which can cause symptoms.

  • Doctors can often diagnose fibrosis and estimate its severity based on results of blood and imaging tests, but sometimes liver biopsy is required.

  • Treatment involves correcting the underlying condition when possible.

Fibrosis develops when the liver is repeatedly or continuously damaged. A single episode of injury, even if severe (as when acute hepatitis damages many liver cells), does not usually cause fibrosis. If injury is repeated or continuous (as occurs in chronic hepatitis), liver cells attempt to repair the damage, but the attempts result in scar tissue. Scar tissue replaces the liver cells and, unlike liver cells, performs no function. Scar tissue can interfere with blood flow to and in the liver, limiting the blood supply for the liver cells. Without enough blood, these cells die, and more scar tissue is formed. Also, blood pressure in the vein that carries blood from the intestine to the liver (portal vein) increases—a condition called portal hypertension (see Portal Hypertension).

Fibrosis can sometimes be reversed if the cause is identified promptly and corrected. However, after months or years of repeated or continual damage, fibrosis becomes permanent.

Causes

Various disorders and drugs can repeatedly or continuously damage the liver and thus cause fibrosis. In the United States, the most common causes are alcohol abuse, viral hepatitis C, and fatty liver not due to alcohol use (nonalcoholic steatohepatitis). Nonalcoholic fatty liver usually occurs in people who have excess body weight, high levels of fats (lipids) and cholesterol in the blood, and/or a high blood sugar level (as occurs in diabetes). Worldwide, viral hepatitis B is a common cause. Sometimes the cause of fibrosis is not known.

Some Conditions That Can Cause Fibrosis of the Liver

Type

Examples

Comments

Certain hereditary metabolic disorders

Alpha 1 -antitrypsin deficiency

Iron overload (hemochromatosis)

Wilson disease

These disorders affect how foods are absorbed, broken down, and/or processed (metabolized) in the body. If foods are not broken down normally, substances can accumulate in various organs (such as the liver) and cause damage.

Infections

Viral infections such as chronic hepatitis B or C

Some infections can affect almost any organ of the body, including the liver. Some, such as hepatitis, affect mainly the liver.

Autoimmune disorders

Autoimmune hepatitis

Primary biliary cirrhosis

Primary sclerosing cholangitis

The body attacks its own tissues (an autoimmune reaction—see Autoimmune Disorders)

In primary biliary cirrhosis and primary sclerosing cholangitis, bile ducts become inflamed, scarred, and blocked.

Disorders that affect blood flow to, in, and out of the liver

Budd-Chiari syndrome (blockage of blood flow out the liver by a blood clot)

Heart failure

Portal vein thrombosis (blockage of the main vein to the liver by a blood clot)

Veno-occlusive disease of the liver (blockage of the small veins in the liver)

When blood cannot leave the liver, the liver enlarges.

When liver cells do not receive enough blood, they die and are replaced with scar tissue.

Veno-occlusive disease is sometimes caused by pyrrolizidine alkaloids. These substances are present in certain herbal products such as bush (rooibos) teas, which are sometimes used for their supposed health benefits.

Drugs

Alcohol

Amiodarone

Chlorpromazine

Corticosteroids

Isoniazid

Methotrexate

Methyldopa

Oxyphenisatin

Tamoxifen

Tetracycline

Tolbutamide

Most drugs must be processed in the liver. Some can harm the liver.

Other disorders

Congenital hepatic fibrosis

Nonalcoholic fatty liver (steatohepatitis)

Congenital hepatic fibrosis damages primarily the liver, gallbladder, and kidneys. It causes fibrosis in the liver and other symptoms. This disorder is present at birth.

In nonalcoholic fatty liver, fat accumulates in the liver and fibrosis develops. This disorder tends to occur in people who have metabolic syndrome (see Metabolic Syndrome).

Symptoms

Fibrosis itself does not cause symptoms. Symptoms may result from the disorder causing fibrosis. Also, if fibrosis progresses, cirrhosis may develop (see Cirrhosis of the Liver). Cirrhosis can cause complications (such as portal hypertension) that cause symptoms (see Portal Hypertension : Symptoms).

Diagnosis

Doctors suspect fibrosis when people have a disorder or take a drug that could cause fibrosis or when routine blood tests to evaluate the liver (liver function tests) indicate that the liver is damaged or is malfunctioning. Tests are then done to confirm the diagnosis, and if fibrosis is present, tests are done to determine its severity. These tests can include imaging tests, blood tests, liver biopsy, and sometimes specialized imaging tests to determine how stiff the liver is.

Imaging tests such as ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI) may show abnormalities that can accompany fibrosis (such as portal hypertension, an enlarged spleen, or cirrhosis). However, they cannot confirm fibrosis.

Certain combinations of blood tests can distinguish between two levels of fibrosis:

  • Absent or mild

  • Moderate to severe

These tests cannot differentiate between degrees of moderate or severe fibrosis.

Liver biopsy (see Biopsy of the Liver) is the most reliable way to detect fibrosis and to identify the disorder causing fibrosis. Biopsy is often done when the diagnosis is unclear. It is also done to determine whether fibrosis has progressed to cirrhosis (for example, in people with hepatitis C). Because liver biopsy is invasive and can cause problems, doctors may first do blood tests to determine the level of fibrosis and then do a liver biopsy only if blood tests indicate that fibrosis is moderate or severe.

Specialized imaging tests can determine how stiff the liver is. The stiffer liver tissue is, the more severe fibrosis is likely to be. These tests (ultrasound elastography, MRI elastography, and acoustic radiation force impulse imaging) use sound waves, applied to the abdomen, to determine how stiff the liver tissue is. Unlike liver biopsy, these tests are not invasive and thus have some advantage. However, these tests are not yet commonly used. In people who are obese, the increased amount of fat in the abdomen can reduce accuracy of the tests.

Treatment

Doctors focus on treating the cause, which often stops or slows further scarring of the liver and sometimes results in improvement. Such treatment may include

  • Using antiviral drugs to eliminate the virus if people have chronic viral hepatitis (see Chronic Hepatitis)

  • Not drinking alcohol if people have alcoholic liver disease (see Alcoholic Liver Disease)

  • Using drugs to remove heavy metals if people have iron overload (hemochromatosis) or Wilson disease (which causes copper to accumulate)

  • Stopping a drug that is causing fibrosis

  • Removing or dissolving a blockage in the bile ducts

  • Losing weight and controlling blood sugar and lipid levels in people with nonalcoholic fatty liver

Drugs used to reduce fibrosis (such as corticosteroids or penicillamine) are usually too toxic to be taken for a long time use. Other drugs that may reduce fibrosis are under study. Silymarin, present in milk thistle, is a medicinal herb sometimes used to treat fibrosis. It appears to be safe but does not appear to be effective.

Resources In This Article

Drugs Mentioned In This Article

  • Generic Name
    Select Brand Names
  • CORDARONE
  • ACHROMYCIN V
  • NOLVADEX
  • LANIAZID
  • OTREXUP
  • No brand name
  • No US brand name
  • CUPRIMINE