• Liver biopsy is the gold standard test for the diagnosis of Autoimmune hepatitis
• Liver biopsy is performed by following methods:
  • Percutaneous liver biopsy with or without ultrasound guidance
  • Transjugular liver biopsy

Histology findings usually found on biopsy:

• Interface hepatitis (ie, piecemeal necrosis) is the histological hallmark
  • There is lymphoplasmacytic periportal infiltrate which invade the limiting plate
  • There is an abundance of plasma cells and eosinophils are usually present
  • Portal lesion spares the biliary tree
• A plasma cell infiltrate lead to plasma cell hepatitis

• Bridging necrosis
• Fibrosis

Fibrosis is present in most patients with autoimmune hepatitis. Without effective therapy, fibrosis starts to connect the portal and central areas, which ultimately leads to cirrhosis.