Allogeneic peripheral blood stem cell transplantation for an acute myeloid leukemia patient with a rare Rh-variant D-- phenotype

Abstract

We here report a rare case of allogeneic peripheral blood stem cell transplantation (allo-PBSCT) for an acute myeloid leukemia (AML) patient with the Rh-variant D-- phenotype. 　 People whose red blood cells (RBCs) have a rare deleted Rh phenotype (D--) readily produce anti-Rh17 alloantibodies (an antibody to the RhCc/Ee protein). This causes clinical complications resulting from RBC destruction due to the interaction of alloantibodies with RBCs carrying the corresponding antigen. Consequently, patients with such variants who have formed alloantibodies pose a challenge for transfusions given the scarcity of compatible donors. In fact, in Japan, only 1 in 200,000 individuals are eligible donors. 　 A 26-year-old male AML patient underwent allo-PBSCT from an HLA-matched sibling donor. He had the rare D-- phenotype and developed anti-Rh17 alloantibodies before allo-PBSCT. Given the scarcity of compatible blood donors for transfusions, the patient required autologous blood donations in preparation for allo-PBSCT. RBC engraftment was prompt during allo-PBSCT; thus, no unscheduled RBC blood transfusion was required. Five months later, his blood type changed to that of his sibling donor, and no irregular antibodies to RBCs were detected.