Clinical features of autoimmune hepatitis diagnosed based on simplified criteria of the International Autoimmune Hepatitis Group

Background: Recently, simplified diagnostic criteria for autoimmune hepatitis have been proposed. Aim: We aimed to evaluate usefulness of the simplified criteria. Methods: We applied the simplified criteria to 176 autoimmune hepatitis patients diagnosed according to the revised scoring system proposed in 1999 (original criteria). Furthermore, in order to compare predictabilities between these two diagnostic criteria, we included 168 patients with other liver disease than autoimmune hepatitis. Results: Of 176 autoimmune hepatitis patients, 85% were diagnosed with autoimmune hepatitis according to the simplified criteria, and patients diagnosed according to the simplified criteria showed a higher frequency of antinuclear antibodies and/or smooth muscle antibodies of 1:80 or greater and slightly higher serum levels of immunoglobulin G than those diagnosed according to the original criteria. However, 30% of male patients, 23% of patients with acute presentation, 50% of patients showing histological acute hepatitis and 46% of patients negative for antinuclear antibodies at presentation were not diagnosed with autoimmune hepatitis according to the simplified criteria. The simplified criteria showed lower sensitivity (85% vs. 100%) and higher specificity (99% vs. 93%) for autoimmune hepatitis than the original criteria. Conclusions: The simplified criteria may be useless for the diagnosis of patients with atypical features, especially patients with histological acute hepatitis.