Background  Many reports of autoimmune hepatitis (AIH) were written in the ‘pre-Hepatitis C era’ and data on the natural history are still incomplete.

Aim  To evaluate the clinical presentation and the natural history of type I AIH.

Methods  Seventy-three consecutive patients with a regular follow-up of at least 2 years were prospectively included in the study. The mean follow-up was 91 ± 61 months.

Results  Patients with ‘acute’ onset at presentation were significantly older than patients with ‘chronic’ onset (P < 0.05) and had significantly higher serum levels of transaminase, γ-glutamyltransferase and bilirubin; Prothrombin time was significantly lower in the said group compared with AIH patients with ‘chronic’ onset. In 4 of 63 (6.3%) female patients, AIH had the onset during pregnancy; in all of them the outcome of pregnancy was favourable. The major events during the follow-up included oesophageal varices (n = 9) and ascites (n = 4), and 60 patients remained in remission while receiving immunosuppression. None of the patients died during the follow-up, but seven patients were transplanted. The cumulative transplant-free probability of survival was 73.5% at 280 months.

Conclusions  Elderly patients have more frequently an acute onset at presentation. Survival in AIH is apparently good; with early diagnosis, and improved medical therapy, liver transplantation for AIH will become a rare event in future.