Diagnosis and Management of Autoimmune Hepatitis
Diagnostic Criteria
- The International Autoimmune Hepatitis Group (IAIHG) scoring system is used to diagnose autoimmune hepatitis (AIH), with a score of ≥10 points indicating probable AIH and ≥15 points indicating definite AIH 1, 2, 3
- Female sex is a positive scoring factor, contributing +2 points to the IAIHG score 1, 4
- High-titer ANA (4+ speckled pattern) is a positive scoring factor, contributing +3 points to the IAIHG score 1, 4
- Elevated IgG and globulin levels are characteristic of AIH, contributing +1 to +2 points to the IAIHG score 1, 4
Diagnostic Evaluation
- Additional autoantibody testing, including smooth muscle antibody (SMA), anti-LKM1, anti-LC1, and anti-SLA, is recommended to support the diagnosis of AIH 2, 4, 6
- Viral hepatitis markers (HBV, HCV, HAV) should be excluded to rule out other etiologies of liver disease 2, 3, 8
- Wilson disease screening (ceruloplasmin, 24-hour urinary copper) is recommended, especially in younger patients 2, 6, 10
Management Approach
- Immunosuppressive therapy should be initiated in patients with probable or definite AIH (≥10 points pre-treatment) who meet treatment criteria, including moderate to severe inflammation, symptomatic disease, or younger age 1, 12
- The standard induction regimen consists of prednisolone 30-40 mg/day (or prednisone 60 mg/day tapering to 20 mg/day over 4 weeks) plus azathioprine 50 mg/day (after checking TPMT activity) 1, 12