Two sister cases of autoimmune hepatitis.

: Two sister cases of autoimmune hepatitis are described. Case 1 involved a 49-year-old woman who suffered from bleeding gums and general fatigue. Her laboratory data showed a marked increase in transaminase levels, an elevated IgG level with titers 1:80 or more of both antinuclear and smooth muscle antibodies and thrombocytopenia. Histology of the biopsied liver revealed chronic active hepatitis with a moderate infiltration of mononuclear cells. A complication of idiopathic thrombocytopenic purpura was determined based on higher titers of PA-IgG and a normal bone marrow findings. Case 2 involved a 54-year-old woman, an elder sister of case 1, who suffered from general fatigue with jaundice. Her laboratory data showed a severe damage of liver function and an elevated IgG level with positive antibodies to nuclear and smooth muscle antigen. Histology of the biopsied liver revealed chronic active hepatitis. Both patients were negative to markers of hepatotrophic agents. Under diagnosis of autoimmune hepatitis, they have been treated with prednisone followed by a significant clinical improvement. HLA types of two patients were Bw54-DR4 and DR4. Among 4 other siblings, the eldest sister suffered from rheumatoid arthritis. The occurrence of two sister cases of type-1 autoimmune hepatitis has rarely reported and the fact would support a role of enviromental factors besides genetic factors for the onset of this disease.