haemolytic disease of the newborn

Question 1

haemolytic disease of the fetus and newborn (HDFN)

Answer 1

transplacental passage of maternal antibodies

causes immune haemolysis of fetal/neonatal RBCs

Question 2

epidemiology

Answer 2

depends on the proportion of the population who are rhesus negative
highest (16%) in caucasian in the UK
anti-D prophylaxis have reduced freq from 1% to 1 in 21,000

Question 3

risk factors

Answer 3

alloimmunisation during first pregnancy, or in second or subsequent pregnancies
failed prophylaxis

Question 4

presentation

Answer 4

antenatally the first indication is the presence of anti-D antibodies
routine USS may show hydrops fetalis or polyhydramnios

clinical signs of severe haemolytic disease:
pallor
hepatosplenomegaly
oedema
petechiae
ascites