ABO型 minor mismatch 生体肝移植後に抗B抗体が長期間遷延した1症例

Abstract

We report a case of hemolytic anemia due to anti-B antibody after minor ABO-mismatched partial liver transplantation from a living donor. The patient was a 5-year-old girl with congenital biliary atresia, and group AB, Rh-positive blood. A partial liver transplant from her group A, D (Rh0) mother was performed. The recipient HLA was A2, 26; B54, 62; DR4, 15, and that of the donor was A2, -; B54, -; DR4, 14. This type of transplantation is the so-called one-way donor-recipient HLA matching. Her hemoglobin fell rapidly from 11.0g/dl to 6.0g/dl between days 10 and 15 after liver transplantation without evidence of bleeding. On day 14, anti-B IgM antibody was found in her serum. On day 16, two units of group O washed red blood cells were transfused, after which no further transfusions were required. This anti-B IgM antibody was thought to be produced from passenger B lymphocytes in the donor's liver. Although this type of antibody usually disappears within 4 weeks, it was continuously detected for about 4 months in this case. The long-term presence of anti-B antibody may be caused by one-way donor-recipient HLA matching.