Background and aims:Autoimmune hepatitis (AIH) is a complex and progressive inflammatory liver disease characterized by immune-mediated destruction of the liver parenchyma, hypergammaglobulinemia, the presence of circulating autoantibodies, and good response to immunosuppressive therapy. Since the prevalence of AIH is relatively rare, data on the clinical course and the long-term outcome are scarce.Patients and methods:We retrospectively analyzed the data of 535 well-documented AIH patients treated at the University Hospital Essen between 2000 and 2020.Results:The majority of patients were middle-aged females (75% women, mean age 45 years) with AIH type 1 (97%). Approximately 32% of patients were diagnosed with cirrhosis due to AIH, 29% had concomitant autoimmune (predominantly autoimmune thyroiditis), and 10% had psychiatric diseases, respectively. Skin tumors were the most common malignant diseases (47% of all tumors), while hepatocellular carcinoma rarely occurred (only six cases). Overall long-term mortality and liver-associated mortality were 9.16% and 4.67%, respectively. However, long-term survival was strongly associated with disease remission.Conclusions:Although AIH is a silent disease and cirrhosis is present in many cases, a favorable long-term prognosis can be achieved by consequent immunosuppressive therapy. The incidence of (liver-associated) complications seems to be lower in comparison to other etiologies, such as viral hepatitis or NASH, and mainly depends on the long-term side effects of immunosuppressive therapy.