Hemolytic Diseases of the Newborn - Krafts Flashcards
Hemolytic Disease of the Newborn
Hemolysis in a newborn or fetus caused by blood-group incompatibility between mother and child
Hemolytic Disease of the Newborn Mechanism
- Baby inherits blood group antigen from dad that are foreign to mom
- Baby’s blood gets into mom’s circulation
- Mom makes antibodies to baby’s blood group antigen
- Mom’s antibodies attack baby’s RBCs
Extramedullary Hematopoiesis
Making red blood cells and platelets outside of the bone marrow; can clog up organs
Hydrops
Heart and/or liver failure causing edema
Jaundice
Unconjugated bilirubin floating around in the blood that is treated with light
Kernicterus
Swollen, edematous brain
Rh Incompatibility
Antibody response of the mom to the D antigen; First baby is usually fine because IgM cannot cross the placenta; second exposure evokes IgG, which does cross the placenta
IAT on the Mom
Indirect antiglobulin test looking for antibodies against D antigen
Rhogam
Anti-D Antibody administered at 28 weeks and within 72 hours of delivery to prevent mom from making her own Anti-D Antibody (cannot cross placental barrier, even though it is an IgG antibody)
Kleihauer-Betke Test or Flow Cytometry
Used to quantify the amount of fetomaternal hemorrhage in order to dose Rhogam
Kleinhauer-Betke Test
- Smear mom’s blood
- Acid bath to remove Adult HbA
- Stain blood smear
- Baby’s cells appear pink
Flow Cytometry for Fetal Cells
- Use mom’s blood
- Apply anti-HbF (Fetal) Antibody
- If present, baby’s cells are INTENSELY positive
ABO Incompatibility
Most Anti-A and Anti-B antibodies are IgM, but neonatal red cells express A and B poorly
Treatment for Hemolytic Disease of the Newborn
Mild: Phototherapy
Severe Case: Total Exchange Transfusion
Mom
