Haematology - Haemolytic Disease of the Newborn

Question 1

Definition
AKA alloimmune HDN/erythroblastosis fetalis

Answer 1

Occurs in type O mother with naturally occurring Anti-A and Anti-B antibodies + Type A/Type B fetus
Can occur in first and all subsequent pregnancies

Question 2

Risk factors

Answer 2

Blood group incompatibility,
Fetomaternal haemorrhage

Question 3

Signs and symptoms

Answer 3

Hemolytic disease caused by ABO incompatibility
- Mild to moderate hyperbilirubinaemia within the first 24 hours of life
- Mild to moderate anaemia
Hemolytic disease caused by Rh inompatability (more severe):
- Hyperbilirubinaemia, kernicterus
- Symptomatic anaemia: pallor, lethargy, tachycardia, tachypnoea
- Hydrops fetalis: severe anaemia induced hypoxia, subcutaneous edema, pleural/pericardial effusion, ascites, s + s of shock
Antenatal presentation:
- Intrauterine growth restriction signals problems with ongoing haemolysis, hypoxia

Question 4

Diagnosis

Answer 4

Doppler ultrasound = antenatal (maternal testing), notes growth restriction/presence of hydrops
Direct Antibody Test (DAT) = the test is done at birth from the cord blood.

Question 5

Treatment

Answer 5

Hematopoietic agents, iron supplements
Phototherapy light therapy