Dynamic contrast-enhanced CT at the early stage confirms two cases of acute liver failure due to acute-onset autoimmune hepatitis with extensive liver necrosis

[Case 1] A 54-year-old female presented with severe liver damage. During diagnosis, contrast-enhanced CT enhanced the area of hypoattenuation on unenhanced CT in the arterial phase, after which the enhanced effect was prolonged to the equilibrium phase. Then, we started immunosuppressive therapy based on the results, including corticosteroid administration, and her hepatitis subsided. [Case 2] A 57-year-old female also presented with severe hepatitis. Contrast-enhanced CT findings were similar to those of Case 1. Since hepatic encephalo-pathy developed and worsened to degree IV, a brain-dead liver transplant was conducted on the 21st day. Nev-ertheless, histological diagnosis was challenging in both cases. Therefore, when unenhanced CT shows hetero-geneous hypoattenuation in the liver and contrast-enhanced CT shows a characteristic blood flow disorder, acute-onset autoimmune hepatitis and corticosteroid treatment should be considered, including in complex se-rological or histological case diagnoses.