Autoimmune Hepatitis in Transition: Advances in Diagnosis, Management, and Future Perspectives

Autoimmune hepatitis (AIH) is a liver disease of unknown etiology, characterized by the presence of autoantibodies, increased immunoglobulin G levels in blood, chronic/persistent liver disorder, and favorable response to immunosuppressive therapy. Although the diagnosis of typical AIH cases has become easier, the absence of disease-specific markers poses challenges when diagnosing atypical cases, such as acute-onset AIH or AIH overlapping with drug-induced liver injury, metabolic liver disease, or other autoimmune disorders. Corticosteroids remain the first-line treatment for AIH; however, azathioprine is now covered by health insurance in Japan and can be used to treat AIH. Expanding treatment options is desirable, particularly for elderly patients and refractory cases. This review aims to provide an overview of the diagnosis, treatment, and prognosis of AIH while introducing historical perspectives and current emerging topics. The prevalence of AIH is increasing in Japan and other countries. Although the prognosis is generally favorable, given the possibility of long-term survival, periodic cancer screenings are advisable owing to the risk of carcinogenesis.