Fetal and Neonatal Alloimmune Thrombocytopenia: evidence based screening

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is the most common cause of thrombocytopenia in otherwise healthy newborns. During pregnancy, fetal blood cells enter the maternal circulation and might result in alloimmunization, the maternal production of antigen-specific alloantibodies. Once these alloantibodies enter the fetal circulation, they can cause damage. Clinical presentation can vary from an asymptomatic thrombocytopenia or relatively harmless bruises and petechiae to severe life-threatening and invalidating intracranial hemorrhages (ICHs). Once alloimmunization is detected and diagnosed, subsequent pregnancies can be treated to prevent the recurrence of bleeding complications. Unfortunately, in absence of population-based screening, alloimmunization is virtually only known after an affected fetus or newborn. Affected infants that might have been prevented if only the alloimmunization was known and treated prior to the occurrence of bleeding complications. Implementation of population-based screening in order to prevent FNAIT needs to be a carefully weighed decision. The benefits of screening need to outweigh the potential harm. To guide careful consideration and decision-making, Wilson and Jungner (W&J) proposed and published ten screening criteria. With this thesis, important evidence is presented that can be used for the fulfillment of the W&J criteria.