Antenatal

Question 1

Red cell antibodies to give rise to HDN

Answer 1

Anti- D
Anti- c
Anti- K
Anti- Fya
Anti- Fyb
Anti- Jka
Anti- Jk3

Question 2

Pathogenesis of HDN

Answer 2

When fetal red cell antigen is different to that of the mother.

Maternal IgG actively transported across the placenta and attach to the surface of fetal red cells.
Antibody- costed fetal red cells are sequestered and destroyed in the fetal spleen giving rise to:
- hepatosplenomegaly
- hydrops

Question 3

Management of suspected FNAIT/ platelet alloimmunisation

Answer 3

Suspected: previous child with FNAIT, or signs on USS ie ventriculomegaly

Screen maternal platelet specific allo- antibodies. If positive:
Screen father: if heterozygous:
Investigate baby with intrauterine FBS:
If baby has FNAIT:
Immunoglobulin to mother is first line
Corticosteroids if not responsive to above
Intrauterine platelet transfusion as last resort

Delivery by CS preferred

Question 4

Diagnostic criteria for hydrops (USS criteria)

Answer 4

Ascites
Pleural effusion
Pericardial effusion >2mm
Skin oedema >5mm on chest and scalp
Polyhydramnios SDP >8 or AFI >24
Placentomegaly- thickness >4cm

At least 2

Question 5

Causes of non- immune hydrops

Answer 5

Chromosomal
- turners, triploidy
- T21/ 18/ 13

Haem
- anaemia- haemorrhage/ abruption/ myeloproliferative/ leukaemia
- thalassaemia
- twin- to- twin transfusion
- fetomaternal haemorrhage
- red cell aplasia

Infection
- parvo
- CMV
- toxo
- syphilis
- varicella

Metabolic
- G6PD deficiency
- pyruvate kinase deficiency

Structural
- cardiac failure
- thoracic- CPAM, diaphragmatic hernia
- gastro- atresia/ fistula, volvulus
- renal- agenesis or obstruction
- lymphatic obstruction