In most newborns, hemolytic disease of the fetus and newborn (HDFN) is a short-term condition that lasts a matter of weeks. The rarer longer-term effect on the health of babies born with HDFN depends on factors such as gestational age at birth and the severity of symptoms.
In these rare cases, HDFN can result in neurodevelopmental delays, brain damage, seizures and even death.
What is HDFN?
Hemolytic disease of the fetus and newborn (HDFN) is an immune-mediated red blood cell (RBC) disorder that occurs when a baby’s RBCs break down quickly, which is called hemolysis. HDFN is caused by a mismatch between a mother’s and her baby’s blood type (A, B, AB, or O) or Rhesus (RhRh factor A protein or antigen found on red blood cells. When an Rh-negative mother carries an Rh-positive fetus, her immune system may make antibodies that attack the fetus' red blood cells.) factor (Rh-positiveRh-Positive A blood type trait that means your red blood cells have the Rh(D) antigen. or Rh-negativeRh-Negative A blood type trait that means your red blood cells lack the Rh(D) antigen.) during pregnancy. Numerous antibodiesAntibody A protein made by the immune system that recognizes and attacks foreign substances, such as bacteria, or in HDFN, fetal red blood cells carrying incompatible antigens. to RBC antigensAntibody A protein made by the immune system that recognizes and attacks foreign substances, such as bacteria, or in HDFN, fetal red blood cells carrying incompatible antigens. can be linked to HDFN, such as those from the ABO and Rh blood groupBlood group A classification of blood based on inherited markers found on red blood cells. The ABO and Rh blood groups are most common in HDFN. systems.
HDFN and the neonatal immune system
The neonatal immune system doesn’t suffer HDFN-related long-term consequences. The antibodies produced by the mother that cross the placenta and break down the baby’s red blood cells while in utero are usually eliminated in the first eight to 12 weeks of life.
However, long-term complications related to HDFN, though rare, can seriously affect an infant’s health and development.
Prognosis of babies with HDFN
Due to advances in routine prenatal screening, preventative measures, early diagnosis and prompt treatment, the prognosis of babies affected by HDFN is generally good. Additionally, the quality of prenatal/postnatal management of HDFN and its associated symptoms play an important role in the future health of babies with HDFN.
Complications of HDFN
Newborns affected by HDFN require immediate and constant monitoring to treat symptoms that can create serious long-term consequences if care is delayed. These include anemiaAnemia A condition that occurs when the body doesn’t have enough healthy red blood cells to carry oxygen to its tissues. In HDFN, anemia occurs when maternal antibodies destroy fetal red blood cells. and hyperbilirubinemiaHyperbilirubinemia A common cause of jaundice, this refers to higher than normal bilirubin levels in the blood. (jaundiceJaundice A common symptom of HDFN, jaundice is caused by excess bilirubin and is characterized by a yellow tint to the skin or eyes.), fatigue, breathing difficulties and difficulties feeding.
Severe anemia can lead to the swelling of internal organs and urgent blood transfusions are sometimes needed. It also leads to hyperbilirubinemia, as when red blood cells break down, this causes the baby’s blood to have high levels of bilirubinBilirubin A yellow substance produced when red blood cells break down. High bilirubin levels in newborns with HDFN can cause jaundice or, in severe cases, brain damage., which the neonate is unable to eliminate on its own.
Treatment includes intensive phototherapyPhototherapy A treatment that uses special blue light to help newborns break down bilirubin and prevent kernicterus., and exchange transfusions if care needs to be escalated to prevent the onset of kernicterusKernicterus A rare but serious brain condition caused by very high bilirubin levels.. Kernicterus is a serious condition that occurs when bilirubin crosses into the baby’s brain. Delays in treatment can lead to long-term health implications such as neurodevelopmental impairment, deafness, seizures and cerebral palsy.
