Clinical Outcomes of Children With Autoimmune Hepatitis in Korea: A Nationwide Multicenter Study

Background: Autoimmune hepatitis (AIH) is a rare chronic liver disease with limited data on long-term outcomes.This study aimed to investigate the clinical characteristics and prognosis of pediatric AIH patients in Korea.Methods: We retrospectively reviewed the medical records of 44 patients diagnosed with AIH under 19 years of age between January 2007 and August 2023 at nine tertiary university hospitals in Korea.Clinical data, including laboratory findings, treatment, and outcomes such as biochemical remission and survival rates, were analyzed. Results:The median age at diagnosis was 12 years, and 57% were female.Type 1 AIH was predominant, and 7% of cases were autoimmune sclerosing cholangitis.Twenty-three percent of patients had coexisting autoimmune diseases.Jaundice was the most common symptom, and 7% of patients had cirrhosis at diagnosis.All patients were seropositive for autoantibodies, with 93% testing positive for antinuclear antibodies.Patients who received an initial corticosteroid dose of 1 mg/kg/day had higher biochemical remission rates from 6 months to 5 years compared to those who received a lower dose.Remission rates did not differ significantly between azathioprine monotherapy and corticosteroid combination therapy.The ten-year overall survival rate was 95%, while the clinical event-free survival was 70%.An initial total bilirubin level 1.0 mg/dL at diagnosis was associated with poorer clinical event-free survival.Conclusion: Type 1 AIH is predominant in Korean children, with a relatively low cirrhosis rate at diagnosis.Standard-dose corticosteroids were effective in achieving biochemical remission.Initial bilirubin levels may serve as a prognostic marker for long-term outcomes.