Abstract: Abstract Object: To summarize the clinical，pathological, immunnological and biochemical features of autoimmune hepatitis(AIH), to improve the rate of diagnosis and decrease the rate of missed diagnosis. Methods: Adopted the descriptive diagnosis standard and scoring system proposed by International Autoimmune Hepatitis Group. 39 cases with AIH were retrospectively analyzed and the clinical manifestations and laboratory examinations were investigated. 40 in-hospital patients of acute hepatitis B patients in the same period were selected as a comparison. Results: Most of AIH patients were the female (97.4%), mainly ranged in age from 45 to 59 (71.8%). Most of acute hepatitis B were male (72.5%) and lessed than 45 years old (85%). In AIH patients, 15 cases (38.5%) were accompanied by other autoimmune diseases. The first-degree relatives of 10 (25.6%) AIH patients were associated with autoimmune diseases. The level of γ-glutamyl transpeptidase (γ-GT) in AIH patients was higher than acute hepatitis B(216.4±158.5 vs 83.4±30.5, P <0.05). The level of γ-GT were greater than 10 times of upper limited normal (ULN) in 15 cases（38.5%）of AIH, and Continuously increased in 8 （20.5%）AIH cases in late stage when ALT has already decreased. The autoantibody positive rate of ANA was high in AIH group, but there are still 4 (10.3%) patients were autoantibodies negative. The main histologic change was interface hepatitis(65.6%). Conclusion: Carefully questioning the history of autoimmune diseases in the first-degree relatives and observing the change of γ-GT can help the diagnosis of AIH.

Key words: Autoimmune hepatitis, Autoantibody, γ-glutamyl transpeptidase, First-degree relatives, Diagnosis