Haemolytic disease of newborn Flashcards
What does haemolytic disease of the newborn do?
Cause haemolysis in neonate
What is haemolytic disease of the newborN?
Incompatability between rhesus antigens on surface of RBC of mother and foetus
What combination of antibodies in mother and baby can cause haemolytic disease of the newborn?
Mother - rhesus D negative
Foetus - Rhesus D positive
What happens in the first preganancy if a woman is RD- and foetus is RD+?
Foetus blood -> maternal circulation
Maternal immune system recognise rhesus antigens on foetus RBCs as foreign and produce antibodies -> SENSITISED
No probelms
When can haemolytic disease of the newborn occur in a first pregnancy?
When sensitisation happens early on eg antepartum haemorrhage
What causes haemolysis in subsequent pregnancies if baby is rhesus D+ and mother has anti-D antibodies?
anti-D antibodies -> placenta -> foetus, attach to rhesus antigens on RBC -> foetal immune system attacks RBC -> haemolysis
What does haemolysis in foetus cause?
Anaemia
High bilirubin
Risk factors for haemolytic disease of the newborn
Alloimmunisation during first pregnancy
Alloimmunisation during second or subsequent pregnancy
Failed prophylaxis
What increases risk of large foetal maternal haemorrhage at delivery?
Traumatic deliveries incl C section
Manual removal of placenta
Stillbirths and intrauterine deaths
Abdo trauma - 3rd trimester
Multiple pregnancies at delivery
Unexplained hydrops fetails
What increases risk of large foetal maternal haemorrhage at delivery?
Traumatic deliveries incl C section
Manual removal of placenta
Stillbirths and intrauterine deaths
Abdo trauma - 3rd trimester
Multiple pregnancies at delivery
Unexplained hydrops fetails
How is anti-D antibodies detected antenatally?
Indirect coombs test
Who has the indirect coombs test performed?
All rhesus negative women at first antenatal visit
Presentation of haemolytic disease of the newborn
Jaundice - yellow amniotic fluid, yellow ver
Pallor
Hepatosplenomegaly
Kernicterus
Hypoglycaemia
Hydops fatalis
What is kerniceterus?
Bilirubin encephalopathy
How does hydrops fetalis present antenatally?
Polyhydraminos - excessive amniotic fluid
How does hydrops fetalis present postnatally?
Subcutaneous oedema
Peridcardial effusion
Plueral effusion
Ascites
Hepatosplenomegaly
Placenta may be thickened
Clinical signs of severe haemolytic disease
pallor
hepatosplenomegaly
oedema
petechiae
ascites
Treatment for prenatal diagnosed haemolytic disease
Intrauterine transfusiom
Investigations for haemolytic disease
Indirect coombs test
Antenatal US
Foetal blood smapling
FBC
Postnatal diagnosis
What does antenatal US detect?
Signs of hydrops fetalis
What does antenatal US detect?
Signs of hydrops fetalis
What tests for foetal anaemia?
Foetal blood sample replaced by
Doppler US of MCA largely replaced foetal blood sampling as initial test
What does an FBC show in haemolytic disease?
Anaemia
Reticulocyte count - up to 40% severe
Bloods when extreme DIC?
Sphistocytes and burr cells may be observed
Neutropenia and thrombocytopenia
What should be done immediately after birth in a rhesus negative mother?
Blood from umbilical cord checked for ABO and Rh blood group
Direct coombd test
Haemoglobin and baseline bilirubin
What should be done immediately after birth in a rhesus negative mother?
Blood from umbilical cord checked for ABO and Rh blood group
Direct coombd test
Haemoglobin and baseline bilirubin
What results after birth support haemolytic disease diagnosis?
Positive coombs test in presence of ABO or Rh incompatability
Management of rhesus disease in utero
- O negative transfusion at 18 weeks
- Successful transfusion delivery 37-38 weeks
- Unsuccessful transfusion delivery - 32 weeks
When deliver baby after successful vs unseuccessful transfusion at 18 weeks?
37-38 weeks
Unsuccessful - 32 weeks
Prognosis after delivery
50% - normal
25% - moderate disease
25% - severe disease
What should be done for babies who have normal haemoglobin and bilirubin levels at birth with rhesus antiboides?
Monitored for late set anaemia at 6-8 weeks
What to do with babies with moderate haemolytic disesae?
May require transfusion
May need phototheraoy to treat significatn hyperbilirubinaemia which may occur within 24 hours after birth
Why do phototherapy in jaundiced babies?
Avoide kernicterus
What should happen when severe haemolytic disease of newborn anticipated?
Attended by a paediatrician trained in neonatal resus and fresh O negative blood immediately available
Management of severe haemolytic disease after birth
Immediate resus
Temo stabilisation
Exchange transfusion
Top up blood transfusions and phototheraoy may be needed
Early administration of IV haemogloblin
What does early administration of IV immunoglobulins do for severe haemolytic disease?
Reduces haemolysis, peak bilirubin levels and need for exchange transfusion
