Rhesus Disease Flashcards
1
Q
what is the rhesus antigen?
A
- an antigen found on surface of RBCs
- within rhesus group, there are many different types of antigen but D antigen most important one
2
Q
pathophysiology of rhesus disease?
A
- occurs in Rh-ve women with a Rh+ve foetus
- if there is mixing of foetal & maternal blood, woman will develop IgM antibdodies towards Rh antigen (do not cross placenta)
- in future pregnancies, IgG antibodies can cross the placenta & cause haemolytic disease in foetus
3
Q
complication in foetus?
A
- haemolytic disease
- IUGR
4
Q
Mx?
A
prevention is key!!
- All Rh-ve mothers given prophylactic Anti-D at 28 weeks, at any sensitising event and at delivery
- only required after birth if baby Rh+ve
5
Q
what are sensitising events?
A
events where mother’s blood comes into contact w blood of foetus that has Rh antigen ie amniocentesis, APH
6
Q
how does Anti-D work?
A
attaches itself to Rh D antigens on foetal blood that is in the mother’s circulation, preventing mother’s immune system from recognising the antigen
7
Q
how do you manage a foetus affected w haemolytic disease?
A
may require early delivery or in utero blood transfusions
8
Q
how is anti-D given?
A
in form of IM injection
9
Q
what is the Kleihauer test?
A
- a test done after any sensitisation event to check how much foetal blood has passed into mother’s circulation
- used after 20 weeks
