The Efficacy of Corticosteroid Therapy in a Patient with Nonalcoholic Steatohepatitis Overlapping Autoimmune Hepatitis: A Case Report

: The overlap of multiple liver diseases can cause the disease activity and severity to worsen rapidly in some cases. We rarely see patients with non-alcoholic steatohepatitis (NASH) with overlapping autoimmune hepatitis (AIH). A 64-year-old woman who had been prescribed oral drugs to treat diabetes and hypertension (metformin 500 mg/day and voglibose 0.9 mg/day, and termisartan 40 mg/day and amlodipine 5 mg/day, respectively) was diagnosed with NASH with histological confirmation. At 68 years of age, her liver injury worsened with an IgG of 2,871 mg/dL and a high serum anti-nuclear antibody (ANA) level of 2,560. We repeated the liver biopsy, which revealed NASH and mild interface hepatitis with some lobular focal necrosis consisting of overlapping AIH. Therefore, she was treated with 30 mg of prednisolone daily. The treatment led to an improvement in her IgG levels and ANA in the serum and an improvement in the histology results.