Genuine acute autoimmune hepatitis has better therapeutic response and prognosis

Heterogeneous diagnostic criteria for acute autoimmune hepatitis (AIH) across studies hinder the characterization of genuine acute AIH. We developed stringent and multidimensional criteria to distinguish acute, acute-on-chronic, and chronic autoimmune hepatitis (A-AIH, AC-AIH, and C-AIH), aiming to elucidate their clinical profiles.

We consecutively enrolled patients diagnosed with definite AIH between 2012 and 2024. All patients were stratified using stringent criteria encompassing onset time (A-AIH: < 6 months), acute presentation (total bilirubin (TB)  ≥ 5 mg/dL or alanine aminotransferase (ALT)/aspartate aminotransferase (AST)  ≥ 10 × upper limits of normal (ULN)), imaging evidence of cirrhosis, and histological fibrosis stage (A-AIH: fibrosis stage ≤ 1). Clinical features and treatment responses were compared across the three groups.

Among 235 patients, 10.6% were classified as A-AIH, 57.9% as AC-AIH, and 31.5% as C-AIH, with a median follow-up of 51.9 (IQR 21.8-78.8) months. The cumulative full biochemical remission (FBR) rate was 92.0% in A-AIH, 75.7% in AC-AIH, and 59.5% in C-AIH (p = 0.003). The median FBR times were 2.9, 5.5, and 14.5 months, respectively (p = 0.002). Liver-related mortality rates were 0%, 8.8%, and 16.2% across the three groups (p = 0.021). Cirrhosis and albumin (ALB) levels were independent predictors of FBR, and ALB was also independently associated with liver-related death.

Patients with A-AIH achieved the highest cumulative FBR rate, whereas those with C-AIH had the poorest treatment response and the highest liver-related mortality.