RESUMEN
INTRODUCTION AND AIM: Autoimmune hepatitis (AIH) may present acutely, which can rapidly progress to fulminant type. This pattern has been described worldwide but is generally under-reported. We aim to describe the clinical presentation and treatment outcomes of patients with acute onset AIH. MATERIALS AND METHODS: A multicenter retrospective cohort study of patients with acute onset AIH. Clinical, biochemical, and histological data were analyzed and the outcomes were reported. RESULTS: Seventy patients were included. The mean age was 33.8±1.5 years and 58.6% were female. Upon initial presentation, 94% had jaundice, 44% had fatigue, 31% had pruritus, and 29% had abdominal pain. Biochemical analysis revealed elevated alanine transaminase (733±463.6), aspartate transaminase (699±423), and total bilirubin (210±181.8). Antinuclear antibody (ANA) was positive in 61% of patients, anti-smooth muscle antibody (ASMA) in 69%, and both in 31%; immunoglobulin G (IgG) was elevated in 86% of patients. Advanced fibrosis was found in 39%. Complete remission was achieved in 74.3%, two patients required liver transplants and six died. No specific biomarkers were identified as predictive of remission; however, advanced age was associated with poor prognosis. CONCLUSION: Acute onset AIH is a disease that requires early diagnosis and management. We confirmed that elevated transaminases are the hallmark of biochemical presentation of acute AIH. High IgG, ANA and ASMA are typically present in such patients upon presentation, however, their absence does not totally exclude the diagnosis. Initial response to treatment was excellent; however, the long-term mortality was higher than the general patient population.