HDFN

Hemolytic Disease of the Fetus and Newborn (HDFN)

A condition where maternal IgG antibodies cross the placenta and attach to the fetal antigen-positive red blood cells, leading to their destruction.

Pathogenesis of HDFN

Occurs when maternal IgG antibodies against fetal red blood cell antigens cross the placenta and lead to hemolysis of fetal red blood cells.

Main clinical feature of HDFN

Fetal anemia resulting in high output cardiac failure and extramedullary hematopoiesis.

ABO Incompatibility

A type of HDFN that is the most common cause today, particularly affecting group O mothers.

Positive DAT (Direct Antiglobulin Test)

Laboratory evidence indicating presence of antibodies coating infant's red blood cells, crucial in diagnosing HDFN.

Treatment for HDFN

Includes phototherapy and exchange transfusion to manage high bilirubin levels and anemia.

Anti-D Immunization

A process in which a Rh-negative mother becomes sensitized by a Rh-positive infant, posing risks in subsequent pregnancies.

Clinical significance of Anti-K antibodies

They can cause severe anemia in the fetus; K antigens are present on immature erythroid precursor cells.

Prenatal Screening for HDFN

Involves typing ABO/Rh and antibody screening during pregnancy to assess risk for HDFN.

Fetal Neonatal Alloimmune Thrombocytopenia (FNAIT)

A condition where maternal platelet antibodies cause destruction of fetal platelets, leading to thrombocytopenia.

Signs of FNAIT

May include petechiae, ecchymosis, GI bleeding, and intracranial hemorrhage in the infant.

Goals of Treatment for FNAIT

To avoid intracranial hemorrhage, including careful monitoring and potential platelet transfusions.

Neonatal Transfusion

The process of transfusing blood to a newborn, particularly when addressing conditions such as hemolytic disease of the fetus and newborn (HDFN).

Intrauterine Transfusion

A type of transfusion performed on a fetus while still in the womb, aimed at addressing conditions like fetal anemia.

Exchange Transfusion

A procedure performed after birth to replace the baby’s sensitized red blood cells with antigen-negative red cells.

Incremental Transfusions

Transfusions given to replace blood volume lost due to routine sampling or minor bleeding.

Rh Immune Globulin (RhIG)

A medication administered to prevent alloimmunization to the D antigen in Rh-negative mothers.

Rosette Test

A qualitative test used to detect fetal Rh-positive cells in a maternal blood sample.

Kleihauer-Betke Test

A quantitative test that determines the number of fetal red blood cells in maternal circulation.

Flow Cytometry

A technique used to distinguish fetal from adult hemoglobin and assess the degree of fetal hemorrhage.

HDFN

Hemolytic Disease of the Fetus and Newborn, a condition caused by the mother's immune response to fetal blood group antigens.

Antigen-negative red cells

Red blood cells that lack specific antigens present on the mother’s antibodies, crucial in transfusion for HDFN treatment.