Hemolysis in Rh-negative female recipient after Rh-incompatible bone marrow transplantation for chronic myeloid leukemia

Hemolysis in an Rh-negative female patient, suffering from chronic m yeloid leukemia and given an allogenic bone marrow transplant from an HLA compatible Rh-positive donor, is reported. An immunohematological study performed before the transplant did not reveal any irregular antibodies. In the days following the transplant, hemolytic anemia developed due to the presence of anti-D specific isoantibody, with a titer of 1:64 that was reduced by means of plasmapheresis. Subsequently, following engraftment, the transplanted marrow started producing Rh-positive erythrocytes, and the isoantibody was gradually consumed until it disappeared completely from the patient's serum. The Authors point out that this complication, related to the persistence after radio-chemotherapy of sensitized clones of the recipient's lymphocytes, can arise from Rh-positive donor marrow transplants in Rh-negative patients, previously sensitized by pregnancies or blood tranfusions.