Comparing alloimmunization in preterm infants after transfusion of fresh unmodified versus stored leukocyte-reduced red blood cells

Purpose: To compare the occurrence of red blood cell (RBC), platelet (PLT), and white blood cell (WBC) antibodies in preterm infants after transfusion s. Methods: A randomized blinded trial was conducted in which preterm infants were transfused either with stored RBCs, prepared by prestorage leukocyte r eduction and transfused throughout 42 days of storage to limit donor exposu re (n = 18), or with fresh RBCs prepared without leukocyte reduction and tr ansfused within 7 days after collection from as many donors as needed to gu arantee freshness (n = 17). Nontransfused preterm infants of comparable bir th weight were control subjects (n = Il). Results: No RBC antibodies were detected in serial blood samples taken duri ng the first 6 months of life. Similarly, no definite WBC antibodies were f ound, although weak reactivity was detected transiently in sera from two in fants. Accordingly, RBC and WBC antibody production did not differ among gr oups. In all, 11% of the transfused the infants exhibited platelet antibodi es: 14% of the infants given stored leukocyte-reduced RBCs and 7% of the in fants given fresh nonleukocyte-reduced RBCs (difference not statistically s ignificant). Conclusions: Preterm infants rarely produce antibodies to blood cell antige ns after RBC transfusions, regardless of whether the exposure is to fresh u nmodified RBCs from several donors or to stored leukocyte-reduced RBCs from a limited number of donors. Therefore, efforts to limit donor exposures or to remove WBCs from blood components cannot be justified simply for purpos es of preventing alloimmunization in neonates.