Methotrexate use and risk of abnormal alanine aminotransferase elevation in children with rare inflammatory diseases: a self-controlled case series analysis using a pediatric electronic health record database in Japan

CONCLUSION: Methotrexate treatment in children with inflammatory diseases increases the risk of liver enzyme elevation, highlighting the necessity of liver function monitoring. Folic acid supplementation may help mitigate the exacerbation of MTX-induced liver injury in pediatric patients.