Acute presentation of autoimmune hepatitis: Does it exist? A published work review

Autoimmune hepatitis (AIH), initially called chronic aggressive hepatitis, is conceptually classified as a primary chronic disease; periportal fibrous expansion and periportal infiltration of mononuclear cells, including plasma cells, have also been considered to be histologically important diagnostic signs of AIH. However, several manuscripts which reported the acute presentation of AIH have been published recently and the reported cases of acute presentation in these manuscripts contained two different clinical entities. One is acute exacerbation of chronic AIH (acute exacerbation form) and the other is genuine acute AIH without chronic histological changes (acute form). It is clinically important to distinguish the acute form from the acute exacerbation form. The reports of the acute form revealed that the existence of centrilobular necrosis without chronic changes was the most important histological finding related to the acute form. Because the elevation of serum levels of immunoglobulin G and antinuclear antibody are not observed in some acute presentation AIH patients, the physician may not consider AIH when they encounter such patients. Therefore, it is very important to bear in mind a possibility of acute presentation AIH when the physician encounters patients with hepatic dysfunction of unknown cause because it became clear that delay of the diagnosis and start of therapy lead to the poor prognosis of AIH. In this review, we outline the current state of acute presentation of AIH including the genuine acute form based on the published clinical studies and case reports.