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Fibrosis of the Liver


Tae Hoon Lee

, MD, Icahn School of Medicine at Mount Sinai

Reviewed/Revised Jan 2024
Topic Resources

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.

Cirrhosis and Fibrosis

Scar tissue replaces the liver cells and, unlike liver cells, performs no function. Scar tissue can distort the liver's internal structure and 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 Portal Hypertension Portal hypertension is abnormally high blood pressure in the portal vein (the large vein that brings blood from the intestine to the liver) and its branches. Cirrhosis (scarring that distorts... read more .

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 widespread and permanent. The scar tissue can form bands throughout the liver, destroying the liver’s internal structure and impairing the liver’s ability to regenerate itself and to function. Such severe scarring is called cirrhosis Cirrhosis of the Liver Cirrhosis is the widespread distortion of the liver's internal structure that occurs when a large amount of normal liver tissue is permanently replaced with nonfunctioning scar tissue. The scar... read more Cirrhosis of the Liver .

Causes of Liver Fibrosis

Various disorders, medications, and substances can repeatedly or continuously damage the liver and thus cause fibrosis (see table ).

The most common causes in the United States are

Metabolic dysfunction–associated steatotic liver disease usually occurs in people who have excess body weight Obesity Obesity is a chronic, recurring complex disorder characterized by excess body weight. Obesity is influenced by a combination of factors that includes genetics, hormones, behavior, and the environment... read more Obesity , diabetes Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Symptoms of diabetes may... read more or prediabetes, and/or high levels of fats (lipids) and cholesterol Overview of Cholesterol and Lipid Disorders The body needs fats (lipids) for growth and energy. It also uses them to synthesize hormones and other substances needed for the body’s activities. The body may deposit excess fat in blood vessels... read more in the blood. This combination of risk factors for fatty (steatotic) liver disease is often referred to as metabolic syndrome Metabolic Syndrome Metabolic syndrome is characterized by a large waist circumference (due to excess abdominal fat), high blood pressure, resistance to the effects of insulin (insulin resistance) or diabetes,... read more . Over recent years, metabolic syndrome leading to metabolic dysfunction–associated steatotic liver disease has become increasingly common in the United States. Worldwide, viral hepatitis B (see table The Hepatitis Viruses) The Hepatitis Viruses The Hepatitis Viruses is a common cause. Sometimes the cause of fibrosis is not known.


Symptoms of Liver Fibrosis

Diagnosis of Liver Fibrosis

  • A doctor's evaluation

  • Sometimes blood tests, imaging tests, or both

  • Sometimes liver biopsy

Doctors suspect fibrosis when people have a disorder or take a medication that could cause fibrosis or when routine blood tests to evaluate the liver Liver Blood Tests Liver tests are blood tests that represent a noninvasive way to screen for the presence of liver disease (for example, viral hepatitis in donated blood) and to measure the severity and progress... read more 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.

Certain combinations of blood tests can distinguish between 2 levels of fibrosis:

  • Absent or mild

  • Moderate to severe

The severity of fibrosis helps indicate the prognosis in people who have chronic viral hepatitis.

Liver biopsy Biopsy of the Liver Doctors can obtain a sample of liver tissue during exploratory surgery, but more often they obtain a sample by inserting a hollow needle through the person's skin and into the liver. This type... read more is the most reliable way to detect and stage (determine the amount of) fibrosis and to identify the disorder causing fibrosis. Biopsy is often done to confirm the diagnosis, to identify the cause of the liver disease, to stage the level of fibrosis or the presence of cirrhosis, as well as to assess the response to the treatment. Because liver biopsy is invasive and can cause complications, doctors may first do blood tests and imaging tests to determine the level of fibrosis and then decide about the need for a liver biopsy. Doctors are increasingly relying on certain specialized imaging tests as noninvasive alternatives to biopsy.

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 (transient elastography, magnetic resonance 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.

Transient elastography and magnetic resonance elastography are being used in people with various liver disorders to diagnose and stage the fibrosis. Additionally, these tests are used to assess the amount of liver fat in people with fatty liver disease. Conventional ultrasonography can be unreliable because results depend on the skill of the person doing the procedure. In contrast, these specialized imaging tests report their measurement in numbers, allowing objective assessment.

Combinations of blood tests and imaging tests, some of them highly specialized, may improve the doctor's ability to accurately assess the degree of fibrosis.

Treatment of Liver Fibrosis

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

No available medication stops the formation of scar tissue effectively and safely. However, drugs that may reduce fibrosis are currently under study. Silymarin, in milk thistle Milk Thistle Milk thistle is a purple-flowered plant. Its sap and seeds contain the active ingredient silymarin, a potent antioxidant and a term often used interchangeably with milk thistle. Antioxidants... read more , or coffee may help protect the liver against fibrosis, but the evidence is not enough to recommend either as treatment.

Drugs Mentioned In This Article

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No brand name available
Milk Thistle XTRA
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