Approaches to understanding and interpreting the risks of red blood cell transfusion in neonates.

In this review, we explore how to assess potential harm related to neonatal transfusion practice. We consider different sources of information, including passive or active surveillance systems such as registries, observational studies, randomised trials and systematic reviews. Future research directions are discussed.

Patient blood management, what does this actually mean for neonates and infants?

Patient blood management (PBM) refers to an evidence-based package of care that aims to improve patient outcomes by optimal use of transfusion therapy, including managing anaemia, preventing blood loss and improving anaemia tolerance in surgical and other patients who may need transfusion. In adults, PBM programmes are well established, yet the definition and implementation of PBM in neonates and children lags behind. Neonates and infants are frequently transfused, yet they are often under-represented in transfusion trials. Adult PBM programmes may not be directly applicable to these populations. We review the literature in neonatal (and applicable paediatric) transfusion medicine and propose specific neonatal PBM definitions and elements.

Antibodies to human neutrophil antigen HNA-4b implicated in a case of neonatal alloimmune neutropenia.

BACKGROUND: Maternal alloantibodies directed against human neutrophil antigens (HNAs) can cause moderate-severe neutropenia in the newborn in a condition known as neonatal alloimmune neutropenia (NAIN). Neonates with NAIN can present with sepsis or be asymptomatic. NAIN has previously been reported as caused by antibodies against HNA-1a, -1b, and -1c; CD16b, -2, -3a, -4a, and -5a; and HLA, but not by antibodies against HNA-4b. We report a case of NAIN due to anti- HNA-4b alloimmunization in a term neonate. CASE REPORT: An infant with persistent and marked neutropenia was suspected of having neonatal alloimmune neutropenia. Blood samples from both parents were investigated for HNA and HLA incompatibilities by molecular typing techniques and the mother for the presence of HNA and HLA antibodies by serologic techniques. RESULTS: Initial results indicated the presence of granulocyte antibodies in the maternal serum, the specificity of which were shown to be anti-HNA-4b. Subsequently, the mother was genotyped as HNA-4b negative and the father as heterozygous HNA-4ab. The child was shown to have inherited the incompatible HNA-4b allele. CONCLUSION: We have demonstrated the first case of NAIN due to maternal alloimmunization against HNA-4b, pending ratification by the International Granulocyte Immunobiology Workshop.