Infection and Autoimmune Liver Diseases

Autoimmune liver diseases (AiLDs) are heterogeneous disorders affecting either the hepatocytes (autoimmune hepatitis, AIH) or the biliary epithelial cells (primary biliary cirrhosis, PBC, and primary sclerosing cholangitis, PSC). Genetic, immunological and environmental factors appear to be involved in the pathogenesis of these conditions. Studies have linked several infectious agents to the development of these diseases and, in particular, to the development of PBC and AIH. The connection between infections and PSC remains largely obscure, however. The most common hypothesis linking infections with AiLDs is based on molecular mimicry and immunological cross reactivity between infectious agents and self-antigens. This chapter discusses those infectious agents investigated in relation to PBC and AIH. We do not discuss PSC because the data are scarce. Notably, the paucity of data is largely due to a lack of studies as opposed to negative findings.