Hemotherapy in patients undergoing blood group incompatible bone marrow transplantation.

The management of hemotherapy in 31 cases of ABO- or Rh-incompatible bone marrow transplantation is described. Our experience confirms that ABO or Rh incompatibility does not adversely affect engraftment, patient survival, or incidence of graft-versus-host disease. Eighteen recipients with ABO antibodies against the donors' red cells (major incompatibility) were managed by different combinations of plasma exchange, transfusion of incompatible donor type red cells, and removal of donor-type red cells from the bone marrow before transplant. The only serious complication was delayed hemolysis in seven of nine patients who received incompatible red cell transfusions before transplant. Thirteen patients received bone marrow containing ABO antibodies against their red cells (minor incompatibility). Five were managed by centrifuging the bone marrow to remove plasma and reduce the amount of antibody. This did not cause substantial loss of stem cell activity (60-100% of original marrow), and no patients had complications related to the marrow transfusion. In contrast, two of seven patients who received uncentrifuged bone experienced hemolysis. Two of four Rh positive recipients who received marrow from an Rh negative donor developed anti-D, possibly due to Rh positive blood components transfused after transplantation. None of eight Rh negative patients who received an Rh positive transplant has developed anti-D. Blood components should be selected to avoid transfusion of incompatible red cells and to avoid transfusion of a large amount of incompatible plasma. This may necessitate use of plasma components of a different ABO type than the red cell components.