血清中存在自身抗体是丙型肝炎患者肝外自身免疫现象主要表现之一。此外还可伴有混合性冷球蛋白血症、肾小球肾炎、迟发性皮肤卟啉症、干燥综合征(sjogren’s综合征)、自身免疫性甲状腺炎、扁平苔癣、特发性血小板减少症等自身免疫性疾病。丙型肝炎病毒(HCV)相关的自身免疫性疾病易发生于老年、女性、HCV持续感染及伴有肝硬化的患者,但其发病机制至今尚未阐明,治疗策略也是我们将要面对的问题。 1．混合性冷球蛋白血症：其发生与HCV感染有关,主要是由于一种B淋巴细胞的良性增殖以及循环免疫复合物沉积于中小血管引起,导致多种器官和组织的病理损害。临床表现呈多样性,常见有紫癜、关节痛、全身性脉管炎、肾小球肾炎及周围神经性病变等。HCV感染可能在混合性冷球蛋白血症的发生中起重要作用。近90％的混合性冷球蛋白血症患者HCV The presence of autoantibodies in serum is one of the major manifestations of extrahepatic autoimmunity in patients with hepatitis C virus. In addition it may be accompanied by mixed cryoglobulinemia, glomerulonephritis, delayed cutaneous porphyria, sjogren’s syndrome, autoimmune thyroiditis, lichen planus, idiopathic thrombocytopenia Disease and other autoimmune diseases. Hepatitis C virus (HCV) -related autoimmune diseases are prone to occur in elderly, females, persistent HCV infection and patients with cirrhosis, but its pathogenesis has not been elucidated yet. The treatment strategy is also a problem we will face. 1. Mixed cryoglobulinemia: its occurrence and HCV infection, mainly due to a benign proliferation of B lymphocytes and the deposition of circulating immune complexes in small and medium blood vessels, resulting in a variety of organs and tissues of the pathological damage. Clinical manifestations were diverse, common purpura, joint pain, systemic vasculitis, glomerulonephritis and peripheral neuropathy and so on. HCV infection may play an important role in the development of mixed cryoglobulinemia. Nearly 90% of patients with mixed cryoglobulinemia HCV