Hemolytic Disease of the Fetus and Newborn (ABO)

Hemolytic Disease of the Fetus and Newborn (ABO) is a condition that affects a baby's blood system. It happens when the mother's immune system attacks the baby's red blood cells because they have different blood types, specifically involving the ABO blood group system. This causes the baby's red blood cells to break down too quickly, leading to anemia and jaundice after birth. The disease mainly affects the liver and blood systems of the newborn. It can cause symptoms like yellowing of the skin and eyes, tiredness, and in severe cases, swelling or heart problems. Early detection and treatment are important to manage the condition and prevent complications.

Hemolytic Disease of the Fetus and Newborn (ABO) is an immune-mediated condition caused by maternal IgG antibodies directed against fetal red blood cell antigens of the ABO blood group system, most commonly when the mother is blood type O and the fetus is type A or B. The core pathology involves hemolysis of fetal erythrocytes due to antibody-mediated destruction, leading to fetal anemia, hyperbilirubinemia, and potential kernicterus. Unlike Rh incompatibility, ABO HDN can occur in first pregnancies and tends to be milder due to the widespread expression of ABO antigens on many tissues, which dilutes the antibody effect. The major clinical significance lies in the risk of neonatal jaundice, anemia, and in severe cases, hydrops fetalis or neurologic damage from bilirubin toxicity. Diagnosis and management focus on identifying maternal-fetal blood group incompatibility and monitoring for hemolysis and hyperbilirubinemia.