The investigation of infants with RhD-negative mothers: can we safely omit the umbilical cord blood direct antiglobulin test?

Historically, the investigation of a neonate at risk of Rhesus D antigen (RhD)-associated haemolytic disease has included a direct antiglobulin test on umbilical cord blood. However, the introduction of routine antenatal anti-RhD prophylaxis has led to a significant number of false positive results and recent studies suggest that a positive cord blood direct antiglobulin test is poorly predictive of subsequent hyperbilirubinaemia. The British Committee for Standards in Haematology guidelines now recommend that a direct antiglobulin test should no longer be performed routinely on umbilical cord blood in infants born to RhD-negative mothers. We review the recent changes in antenatal management of RhD-negative mothers and their impact on the neonatal presentation of RhD-associated haemolytic disease of the newborn that underpin this recommendation. We conclude that there is convincing evidence to support the guidelines. Finally, we consider how babies born to RhD-negative mothers should be investigated and consider alternative strategies to detect neonatal hyperbilirubinaemia.