Suppression of erythropoiesis by intrauterine transfusions in hemolytic disease of the newborn: use of erythropoietin to treat the late anemia.

Hemolytic disease of the fetus and newborn has three phases of anemia: in utero, in the first week of life, and in the weeks and months after birth. Intrauterine transfusions can ameliorate the severity of both fetal and early anemia, but late anemia and the need for transfusion remain significant problems. Bone marrow hypoplasia--probably a result of suppression of erythropoiesis from the intrauterine transfusions--was documented in the three patients tested in our study. Because erythropoietin (EPO) levels have been found to be low (i.e., normal) in these previously transfused patients despite the degree of anemia, we treated four affected infants with EPO, 200 microliters/kg subcutaneously three times a week, and noted reticulocytosis and increased hemoglobin values 2 to 4 weeks later. One patient again had reticulocytopenic anemia when the EPO therapy was stopped but responded to retreatment. Our study indicates that EPO treatment may be effective in the management of late anemia and could help to decrease the need for postnatal transfusions.