Azathioprine Therapy for Autoimmune Hepatitis

Introduction to Azathioprine Therapy

• The American Association for the Study of Liver Diseases recommends starting prednisolone at 30 mg/day, then adding azathioprine 50 mg/day after 2 weeks, increasing to a maintenance dose of 1-2 mg/kg/day while tapering prednisolone to 10 mg/day over 4 weeks 1, 2, 3

Pre-Treatment Assessment and Patient Evaluation

• The European Association for the Study of the Liver suggests checking TPMT activity to identify patients at risk for severe myelosuppression, particularly those with pre-existing leucopenia 4, 5
• Obtain baseline complete blood count, liver function tests, and renal function 4, 5

Initial Dosing Protocol and Treatment Strategy

• The American Association for the Study of Liver Diseases recommends initiating azathioprine at 50 mg/day when bilirubin is below 6 mg/dL, with a 2-week delay to allow prednisolone to begin controlling inflammation 1, 2, 3
• Increase azathioprine to a maintenance dose of 1-2 mg/kg/day based on tolerance and TPMT status 1, 2, 4, 5

Monitoring Protocol and Response Assessment

• The European Association for the Study of the Liver suggests monitoring CBC and LFTs weekly during initial dose escalation 4
• Assess treatment response at 4-8 weeks, expecting serum aminotransferases to improve within 2 weeks 9

Steroid Tapering Strategy and Treatment Duration

• The American Association for the Study of Liver Diseases recommends reducing prednisolone by 2.5 mg/month while monitoring liver tests, targeting a dose of 5-10 mg/day for long-term maintenance 4, 5
• Continue combination therapy for at least 2 years and for at least 12 months after transaminase normalization 4, 5, 9

Special Considerations for Severe Disease and Therapeutic Drug Monitoring

• The American Association for the Study of Liver Diseases suggests using high-dose intravenous corticosteroids immediately in patients with acute severe autoimmune hepatitis, liver failure, or bridging necrosis 1, 2
• Contact a liver transplant center if MELD score does not rapidly improve within 7 days 1, 2, 4