Early alloimmunization in an infant to red cell antigens—Rare but possible in the ‘right’ circumstances

Abstract Background Red blood cell (RBC) alloimmunization is rarely reported in infants less than 4–6 months of age. Methods/Materials Blood group and antibody screening used the gel card technique. All blood products were leukoreduced. All RBC doses transfused were group O, E‐neg, K‐neg but the pooled platelets transfused on day 45 and 61 included donors who were K‐pos, and that transfused on day 61 also included an E‐pos donor. Results We report a group O neonate with haemophagocytic lymphohistiocytosis (HLH) who developed alloantibodies to E and K antigens at 65 days (9 weeks) of age. Conclusion HLH is an inflammatory, ‘hyperimmune’ state, and alloimmunization is more likely when inflammation is present. If significant inflammation is present, transfusions should be avoided if possible.