Anti-nuclear antibody-negative immunoglobulin G4-associated autoimmune hepatitis mimicking lymphoproliferative disorders.

Immunoglobulin G4 (IgG4)-associated autoimmune hepatitis (AIH) is a very rare subtype of autoimmune hepatitis and characterized by marked elevated serum IgG and hepatic infiltration of IgG4-expressing plasma cells. Pathologic confirmation of hepatic IgG4-expressing plasma cells is usually required for the final diagnosis of IgG4-associated AIH. Herein, we report the case of a 47-year-old female diagnosed with autoantibody-negative IgG4-associated AIH mimicking lymphoproliferative disorders.