A Case of Autoimmune Hepatitis during Brodalumab Treatment for Psoriasis.

Autoimmune hepatitis (AIH) is a chronic inflammation of the liver caused by hepatocyte-specific autoantigens. Psoriasis is a chronic inflammatory skin disease characterized by a skewed interleukin-17 immune response and dysregulated epidermal hyperproliferation and differentiation. Patients with psoriasis have a higher risk of AIH. Some evidence indicates that AIH is triggered by treatment with certain drugs. Brodalumab is a human monoclonal antibody against interleukin-17 receptor A and is used to treat psoriasis. A 70-year-old Japanese man with psoriasis had elevated serum levels of transaminases and bilirubin, positive antinuclear antibodies, and high serum IgG levels after 11 months of brodalumab treatment. Histological analysis of liver tissue revealed interface hepatitis with lymphoplasmacytic infiltration. AIH was diagnosed and treated with prednisolone, which improved his symptoms. This is the first case of AIH during brodalumab treatment for psoriasis. The relationship between brodalumab and AIH should be further examined, and the risk of AIH in psoriatic patients treated with brodalumab should be carefully considered.