Five Pathogenetic Classifications for Alloimmune Hemolytic Disease of the Fetus and Newborn

Maternal alloantibody-induced hemolytic disease of the fetus and newborn (HDFN) remains a significant concern worldwide. Alloimmune HDFN can be pathogenetically named by the specific alloantibodies involved. Moreover, four mechanistic pathway types are generally recognized in clinical practice: classical or extravascular hemolysis; immune-pressure-escaped, also known as antibody-mediated antigen-modulation; apoptotic or dysplastic, and failed transaction. Another proposed pathway is worthy of discussion: lactation-mediated. Management strategies for alloimmune HDFN should take account of these underlying mechanisms.