Autoimmune Hepatitis

Overview – Autoimmune Hepatitis

Autoimmune hepatitis is a chronic inflammatory liver disease caused by a dysregulated immune response in which the body attacks its own hepatocytes. It often presents with non-specific symptoms or may be picked up incidentally, but can progress to fibrosis and cirrhosis if left untreated. Strongly associated with other autoimmune conditions, this condition typically requires lifelong immunosuppression. Prompt diagnosis is critical, as most patients respond well to steroid-based therapy. This article outlines the key features, investigations, and management strategies relevant to final-year medical students.

Definition

Autoimmune hepatitis is a chronic, progressive inflammatory liver disorder resulting from an immune-mediated attack on hepatocytes, leading to hepatic necrosis, fibrosis, and potentially cirrhosis.

Aetiology

• Autoimmune in origin
• Strong associations with other autoimmune conditions:
  • Pernicious anaemia
  • Autoimmune thyroiditis
  • Coeliac disease
  • Autoimmune haemolytic anaemia

Pathogenesis

• Loss of immunological tolerance → hepatocyte injury
• Inflammatory infiltrate targets liver tissue
• Leads to progressive:
  → Hepatocellular necrosis
  → Fibrosis
  → Cirrhosis

Clinical Features

Symptoms

• Often asymptomatic – may be diagnosed incidentally
• Fatigue
• Fever
• Polyarthritis
• Pleuritic chest pain

Signs

• Jaundice
• Cutaneous signs of chronic liver disease:
  • Striae
  • Ascites
  • Acne

Investigations

• Liver function tests (LFTs):
  • ↑↑ ALT & AST (often disproportionately raised)
• Autoimmune markers:
  • ANA (antinuclear antibody) positive
  • Anti-liver antibodies (e.g. anti-smooth muscle antibody, anti-LKM1)
• Consider liver biopsy if diagnosis uncertain

Management

• First-line treatment:
  • Corticosteroids (e.g. prednisolone)
• Steroid-sparing agents:
  • Azathioprine
• Severe/refractory cases:
  • Liver transplantation

Prognosis

• 80% achieve remission with appropriate therapy
• Most patients require lifelong immunosuppression
• Risk of progression to cirrhosis if untreated

Differential Diagnosis

• Viral hepatitis
• Primary biliary cholangitis
• Primary sclerosing cholangitis
• Wilson’s disease
• Non-alcoholic steatohepatitis (NASH)

Summary – Autoimmune Hepatitis

Autoimmune hepatitis is a chronic inflammatory liver disease that can present subtly but carries the risk of cirrhosis if untreated. With strong links to other autoimmune conditions, its diagnosis hinges on elevated liver enzymes and the presence of autoimmune antibodies. Immunosuppressive therapy, usually combining corticosteroids with azathioprine, is effective in most cases. For a broader context, see our Gastrointestinal Overview page.