Introduction
A pathology of the liver that is characterized by excessive accumulation of certain proteins like collagen, which form the extracellular matrix, is called liver fibrosis. It is a consequence of long-standing liver diseases. It is usually a response of the body to ongoing liver injury, inflammation, or chronic liver dysfunction.
What Is Liver Fibrosis?
Liver fibrosis is a medical condition in which the healthy tissues of the liver are scarred, due to which the functions of the kidneys are impaired. It is the initial stage of liver scarring and can be reversed. If the liver cells get damaged due to factors like viral infection, autoimmune disease, or certain medications, the body attempts to repair the damaged tissue. This process of repair involves activating the cells in the liver, which help to produce collagen.
Although some degree of fibrosis can be healed, persistent and prolonged liver injury could result in uncontrolled deposition of collagen, leading to liver fibrosis. Over time, the scar tissue which has been accumulated can distort the liver architecture and lead to impaired functions, which may, at times, progress to cirrhosis.
What Causes Liver Fibrosis?
Liver fibrosis is due to liver injury or inflammation. If the liver cells stimulate wound healing, excess proteins like collagen and glycoprotein may build up in the liver. Later, even after multiple self-repair attempts, the liver may find it challenging to repair itself. So the excess protein released by the scar tissue is the cause of fibrosis.
A few other liver conditions that cause liver fibrosis are listed below:
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Autoimmune hepatitis.
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Biliary obstruction.
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Iron overload.
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Viral hepatitis.
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Alcoholic liver disease.
The common cause of this condition is nonalcoholic fatty liver and due to long-term excessive drinking of alcohol.
What Are the Symptoms of Liver Fibrosis?
It could be very challenging to diagnose liver fibrosis in the early mild or moderate stage, as the condition may not express any symptoms. Unless the liver is highly damaged, the chances of symptoms are less. When an individual has liver fibrosis, they exhibit the following symptoms, although all symptoms may not pertain to an individual.
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Appetite loss.
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Nausea.
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Unexplained weight loss.
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Weakness.
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Jaundice.
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Difficulty in thinking.
What Are the Stages of Liver Fibrosis?
After collecting a small amount of tissue for biopsy, the doctor may thoroughly examine the cause of the condition and aim to treat the root cause for better results. The biopsy is viewed under the microscope to look for any abnormalities and to determine the extent of damage. Determining the degree of fibrosis can be challenging as only a tiny sample of tissue is collected. Various scales are used to define the stages of fibrosis. They are:
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Metavir scale.
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Ishak scale.
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Batts-Ludwig scale.
These scales have a similar scoring system by taking into account the effect of fibrosis on the portal vein. This vein aids in transporting blood from the intestine to the liver.
The Metavir scoring system is mentioned below. It typically rates the progression of the condition.
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A0 - No activity.
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A1 - Mild activity.
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A2 - Moderate activity.
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A3 - Severe activity.
This scoring system also measures the degree of fibrosis
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F0 - Absence of fibrosis.
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F1 - Portal fibrosis with no septa.
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F2 - Portal fibrosis with infrequent septa.
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F3 - Numerous septa but no cirrhosis.
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F4 - Cirrhosis.
Cirrhosis defines the scar tissue buildup in the liver. It may also occur due to unchecked fibrosis.
The advanced stage of fibrosis an individual may possess, according to this system, is A3F3.
The Ishak fibrosis scoring system is a little complex. It is typically numbered from 0 to 6.
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0 - Absence of fibrosis.
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1 - Expansion of some portal areas with short fibrous septa.
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2 - Expansion of most portal areas with short fibrous septa.
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3 - Expansion of most portal areas with sporadic portal-to-portal bridging.
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4 - Expansion of portal areas with significant portal-to-portal central bridging.
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5 - Significant portal to portal and portal to central bridging with sporadic nodules.
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6 - Definite cirrhosis.
The most advanced stage before developing cirrhosis in this scoring system is stage 5.
The Batts-Ludwig scale is a simpler system and is commonly used in the United States. The scale is explained below:
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0 - Lack of fibrosis.
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1 - Portal fibrosis.
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2 - Rare portal-to-portal septa.
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3 - Fibrous septa.
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4 - Definite cirrhosis.
In this scaling system, the advanced stage of fibrosis before developing cirrhosis is stage 3.
How to Diagnose Liver Fibrosis?
The diagnosis of liver fibrosis involves liver biopsy, nonsurgical tests, and transient elastography, which help to identify the severity of the condition.
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Liver Biopsy - It is a condition in which a tissue sample of the liver is examined for the presence of any scars or fibrosis. It is a gold standard technique for testing fibrosis.
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Transient Elastography - An imaging test that measures liver stiffness, especially when an individual has scarred tissue, is called transient elastography. The test uses low-frequency sound waves. There are chances of obtaining false positive results when the liver tissue appears stiff, but the biopsy reports do not show any signs of scarring.
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Nonsurgical Tests - These tests are performed by doctors as they are minimally invasive.
What Is the Treatment of Liver Fibrosis?
Liver fibrosis is treated by understanding the root cause of the condition. For example, chronic liver viral infections are treated with antiviral medications. This suppresses viral replication and reduces liver inflammation. If the fibrosis is due to excessive alcohol consumption, it is better to limit the alcohol intake to prevent further damage. Antioxidant supplements help to decrease oxidative stress and prevent further liver impairment. Ursodeoxycholic acid, another medication, may be prescribed to improve liver functions and slow the disease progression. In severe cases of liver fibrosis, a liver transplant may be advised. In addition, regular monitoring of liver function and fibrosis progression is important to assess the effectiveness of the treatment and to make the required dosage alterations for better progression.
Conclusion
Liver fibrosis is an important pathological condition that occurs due to chronic liver injury and inflammation. It involves excessive accumulation of collagen and other proteins that form scar tissue. If the condition is left untreated, the disease may further progress, resulting in liver cirrhosis. Early detection and management can prevent further liver complications.
