Beer Andrea, Dienes Hans Peter
Department of Pathology, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Ann Transl Med. 2021 Apr;9(8):733. doi: 10.21037/atm-20-5084.
Liver biopsy is an essential and necessary element in the diagnosis and management of autoimmune hepatitis, and is of very special importance in the scoring system for diagnosis. Histopathology shows moderate to severe inflammatory infiltrates with abundant plasma cells in the enlarged portal tracts with interface hepatitis and moderate to severe necroinflammatory lesions in the lobules with lymphoplasmacytic reaction. Regeneration develops with rosette formation and regenerative nodules. One important issue is the differentiation between acute onset of autoimmune hepatitis and a flare up of chronic disease; this cannot be diagnosed in some cases clinically and therefore requires a biopsy to evaluate the stage of the disease. There are some variants of the disease with cholestatic features such as autoantibody negative autoimmune hepatitis and giant cell hepatitis as well as overlap syndromes with primary biliary cholangitis and primary sclerosing cholangitis. Clinically, three types of autoimmune hepatitis are differentiated according to autoantibody formation and the clinical picture, however, histopathologically there is no difference between these three types. Differential diagnosis of autoimmune hepatitis includes drug-induced liver injury with minocycline, alpha methyldopa, nitrofurantoin and checkpoint inhibitors such as infliximab. Wilson´s disease is also an important differential diagnosis especially in young adults. A liver biopsy is mandatory to confirm the diagnosis of autoimmune hepatitis but histopathology alone is not conclusive.
肝活检是自身免疫性肝炎诊断和管理中必不可少的要素，在诊断评分系统中具有非常特殊的重要性。组织病理学显示，在扩大的汇管区有中度至重度炎症浸润，伴有大量浆细胞，存在界面性肝炎，小叶内有中度至重度坏死性炎症病变，并伴有淋巴浆细胞反应。再生表现为玫瑰花结形成和再生结节。一个重要问题是区分自身免疫性肝炎的急性发作和慢性疾病的发作；在某些情况下，临床上无法做出诊断，因此需要进行活检以评估疾病阶段。该疾病存在一些具有胆汁淤积特征的变异型，如自身抗体阴性的自身免疫性肝炎、巨细胞肝炎以及与原发性胆汁性胆管炎和原发性硬化性胆管炎的重叠综合征。临床上，根据自身抗体形成和临床表现可区分三种类型的自身免疫性肝炎，然而，在组织病理学上这三种类型之间并无差异。自身免疫性肝炎的鉴别诊断包括由米诺环素、α-甲基多巴、呋喃妥因和英夫利昔单抗等检查点抑制剂引起的药物性肝损伤。威尔逊病也是一个重要的鉴别诊断，尤其是在年轻人中。确诊自身免疫性肝炎必须进行肝活检，但仅靠组织病理学并不具有决定性。
