Paediatric autoimmune liver disease in Europe, the prospective ERN R-LIVER registry

BACKGROUND & AIMS: Most literature on paediatric autoimmune liver disease (P-AILD) comprises single-centre, retrospective studies. This study aims to describe robust, real-world data for P-AILD during the first year following diagnosis, utilising data from the prospective European Reference Network (ERN) R-LIVER registry. METHODS: All patients younger than 18 years with autoimmune hepatitis (AIH) or autoimmune sclerosing cholangitis (ASC) enrolled in the ERN R-LIVER registry from January 2017 to October 2023 and with >12 months of follow-up were included. Each participating centre recorded data from three time points: diagnosis, 6 and 12 months. RESULTS: A total of 116 patients with P-AILD were enrolled. Seventy-one patients had AIH1, eight had AIH2, and 37 had ASC. At diagnosis, 27% had cirrhosis. Large duct disease was diagnosed in 45% of ASC. Inflammatory bowel disease was present in 14% at diagnosis. No differences were found in presentation and outcome between AIH1 and 2. Most patients (94%) began treatment with standard therapy (prednisolone with/without thiopurines), and 80% were kept on it during the first year. Complete biochemical remission was achieved by 44 (42%) at 6 months and by 45 (42%) at 1 year, while normal ALT (