METAVIR Score: What the Numbers Mean

Use the METAVIR score to understand your liver biopsy

An autopsied liver showing a dense network of scar tissue, called cirrhosis. A biopsy from this liver would probably score F4.
What is a Metavir score, what does it measure, and why is it helpful with liver disease?. CDC/ Dr. Edwin P. Ewing, Jr.

Sometimes it seems we're surrounded by all kinds of scores. For example, if you're buying a car or house, you'll be very familiar with your credit score. In high school or college, you're often judged by another type of score, your GPA. Similarly, if you have chronic hepatitis C, you may also have a score: the METAVIR score, which assesses the health of your liver.

What Is the METAVIR Score?

The Metavir score, simply put, is a test to determine the level of fibrosis of your liver.

Liver fibrosis, which may lead to cirrhosis of the liver, is a hallmark sign of chronic liver disease. Therefore, physicians will want to evaluate the presence and stage of fibrosis in any patient with a chronic liver disease, including hepatitis C. Blood tests are limited in their ability to evaluate liver fibrosis, and a liver biopsy is the best way to gain insight into the health of the liver.

The METAVIR score provides a model for interpreting a liver biopsy. When this biopsy is performed, doctors need a reliable way to quantify what is seen under the microscope. This scoring system assigns two standardized numbers:

  • One to represent the degree of inflammation
  • One to represent the degree of fibrosis

What Does My METAVIR Score Mean?

The Metavir score grades the degree of fibrosis on a 5-point scale from 0 to 4. The activity, which is the amount of inflammation (specifically, the intensity of necro-inflammatory lesions), is graded on a 4-point scale from A0 to A3.

Fibrosis score:
F0 = no fibrosis
F1 = portal fibrosis without septa
F2 = portal fibrosis with few septa
F3 = numerous septa without cirrhosis
F4 = cirrhosis

Activity score:
A0 = no activity
A1 = mild activity
A2 = moderate activity
A3 = severe activity

Why Is a METAVIR Score Helpful?

Your METAVIR score is one of many "tools" your doctor can use to help determine your treatment and monitor your progress.

Sometimes a score of two or greater suggests that treatment should begin. This is not always the case though, because individualized treatment can also be recommended for people with a lower score.

Like most evaluations, the METAVIR system has its strengths and weaknesses. Other scoring systems are available, such as the Knodell score (also called the histologic activity index, or HAI). However, the METAVIR score is simple to use and is popular in many clinics.

Other methods of evaluating fibrosis which do not require a liver biopsy are being evaluated in studies, but at the current time a liver biopsy offers the best measure of degree of fibrosis present.

Limitations of the Metavir Score

While the Metavir score can be a helpful measure to determine if and when treatment for hepatitis C should be initiated, it has limitations as well. Different people with the same Metavir score may be very different as mentioned above, and treatment needs to be individualized rather than relying on the score alone to choose treatments.

A Metavir score is also limited by the quality of the liver biopsy. Small biopsy specimens may not allow physicians to adequately determine a score representative of the whole.

There can also be significant heterogenicity or variability of inflammation and fibrosis in different regions of the liver, with the Metavir score being derived from only one area. In this way the score may either overestimate or underestimate the amount of inflammation or fibrosis present.

A Word From Verywell

Generally, an understanding of the stage of fibrosis is valuable for guiding treatment decisions. For example, the level of fibrosis can indicate the likelihood of treatment response (more advanced cases will usually have a poorer response to treatment).

In addition, if fibrosis progresses slowly, it may be preferable to wait before starting treatment with antiviral therapy.

Finally, using the METAVIR system, doctors can gain insight and make an estimation about when cirrhosis may develop. 

On a global scale, comparing Metavir scores in different regions around the world allows researchers to better assess the natural history of hepatitis C.

Sources:

Fiel, M. Histological Scoring Systems for Chronic Liver Disease. UpToDate. Updated 01/30/15.

Kumar, Vinay, Abul K. Abbas, and Jon C. Aster. Robbins and Cotran Pathologic Basis of Disease. Philadelphia: Elsevier-Saunders, 2015. Print.

Wilkins, T., Akhtar, M., and E. Gititu. Diagnosis and Management of Hepatitis C. American Family Physician. 2015. 91(12):835-842.

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