Centrilobular necrosis

Histopathology of early centrilobular hepatic necrosis of shock liver (intermediate magnification)

Centrilobular necrosis is a pathological condition affecting the liver, characterized by the necrosis of hepatocytes around the central vein (also known as the central lobular vein) in the liver lobules. This condition is significant because it indicates damage to the liver, an organ crucial for metabolism, detoxification, and bile production. Centrilobular necrosis is often associated with various liver diseases, including toxic liver injury, ischemia, and certain infectious diseases.

Causes

Centrilobular necrosis can be caused by several factors, including:

• Toxic liver injury: Exposure to toxic substances, such as alcohol, drugs (e.g., acetaminophen overdose), and environmental toxins, can lead to liver damage and centrilobular necrosis.
• Ischemia: Reduced blood flow to the liver, often due to heart failure or circulatory shock, can cause ischemic injury to the liver cells, particularly affecting the centrilobular regions.
• Viral hepatitis: Certain types of viral hepatitis, especially those with a severe course, can lead to centrilobular necrosis.
• Hypoxia: Low oxygen levels in the blood can cause hypoxic injury to the liver cells, with the centrilobular regions being particularly vulnerable.

Pathophysiology

The liver is divided into lobules, each centered around a central vein. The hepatocytes (liver cells) near the central vein are the most distant from the oxygen-rich blood supply that enters the liver lobule through the portal triad, making them more susceptible to damage from reduced oxygen supply or exposure to toxins. In centrilobular necrosis, these hepatocytes undergo necrosis, which can lead to liver dysfunction. The extent of the damage and the liver's ability to regenerate determine the clinical outcome.

Symptoms

Symptoms of centrilobular necrosis may vary depending on the underlying cause and the extent of liver damage. They can include:

• Jaundice (yellowing of the skin and eyes)
• Fatigue
• Abdominal pain
• Nausea and vomiting
• Loss of appetite
• Swelling in the legs and abdomen due to fluid accumulation

Diagnosis

Diagnosis of centrilobular necrosis involves a combination of clinical evaluation, laboratory tests, and imaging studies. Liver function tests can reveal elevated liver enzymes, indicating liver damage. Imaging studies like ultrasound or MRI can assess the liver's structure. A liver biopsy is the definitive method for diagnosing centrilobular necrosis, allowing direct observation of the necrotic hepatocytes around the central veins.

Treatment

Treatment of centrilobular necrosis focuses on addressing the underlying cause and supporting liver function. This may include:

• Avoiding alcohol and hepatotoxic drugs
• Managing heart failure or circulatory shock to improve blood flow to the liver
• Antiviral therapy for viral hepatitis
• Supplemental oxygen for hypoxia

In severe cases, liver transplantation may be considered if liver function is significantly compromised.

Prevention

Preventing centrilobular necrosis involves minimizing risk factors for liver damage, such as avoiding excessive alcohol consumption, using medications responsibly, and managing chronic conditions that can lead to reduced blood flow to the liver.