[Pure red cell aplasia after allogeneic transplantation of ABO incompatible hematopoietic stem cells].

ABO incompatibility in allogeneic bone marrow transplantation may be associated with incomplete or delayed erythroid engraftment, being pure red cell aplasia (PRCA) the most severe complication in this setting. Attempts for the treatment of PRCA have been made with erythropoietin or with plasmapheresis with relative success, and some authors have reported the reversibility of PRCA with antilymphocyte globulin (ALG or ATG), based on the assumption that PRCA might be immunologically mediated. We report herewith a patient with acute leukemia who developed post--BMT pure red cell aplasia. His sibling donor (sister) was HLA identical and ABO incompatible, having low agglutinin titers against donor's blood group. PRCA did not improve after treatment with erythropoietin or a boost of hematopoietic progenitor cells obtained from donor's peripheral blood but the problem was resolved completely after treatment with ALG.