Abstract: Objective This study was conducted to investigate the clinical and liver histopathological features in patients with acute (AP-AIH) and non-acute presentation of autoimmune hepatitis (NAP-AIH). Methods 30 patients with AP-AIH and 22 patients with NAP-AIH were encountered in our hospital between October 2017 and October 2022, and all patients underwent routinely liver biopsies. The clinical materials were retrieved from standardized electronic medical record data bank in our hospital. Results There were no significant differences as respect to the ages (54.0±14.5 yr vs. 53.4±15.0 yr) and the gender (male for 23.3% vs. 22.7%) between the two groups (P>0.05); serum ALT, AST, bilirubin, ALP, GGT and IgG levels in patients with AP-AIH were 714.4(153.0, 2061.0)U/L, 590.5(147.0,2168.0)U/L, 81.6(43.3, 106.2)μmol/L,146.2(70.7,164.0)U/L, 81.4(38.5, 150.3) U/L and 220.0(128.0, 245.1)mg/L, all significantly higher than [116.5(85.0,172.0)U/L,105.8(78.0, 176.0)U/L,23.4(17.4, 30.8)μmol/L, 113.2(66.7, 176.4)U/L, 83.6(41.6, 153.8) U/L and 142.5(90.6, 243.7)mg/L, respectively, P<0.05] in those with NAP-AIH; the response rate to standardized immunosuppression therapy in patients with AP-AIH was 80.0%, much higher than 54.5%(P<0.05)in those with NAP-AIH; the liver histological examination showed that the incidences of hepatocellular necrosis, moderate to severe cobblestone appearance of hepatocytes, hepatic rosette formation in cobblestone appearance areas, prominent plasma cell invasion in the liver parenchyma and moderate to severe interface hepatitis in patients with AP-AIH 76.7%, 50.0%, 20.0%, 33.3% and 56.7%, all significantly higher than 40.9%, 22.7%, 0.0%, 13.6% and 18.2% (P<0.05) in those with NAP-AIH. Conclusion The clinical and histological features in patients with AP-AIH are consistent with acute liver injuries, and respond to immunosuppression therapy relatively satisfactory.

Key words: Autoimmune hepatitis, Acute presentation, Histopathology, Response