Hemolytic disease of the fetus & newborn

Question 1

How much blood is required to generate an alloimmune response?

Answer 1

0.03mL is adequate.

Question 2

What are the most common antigenic causes of HDFN? Which are most severe?

Answer 2

> D (falling), >K, >E

>K is most severe. >c is quite severe as well.

Question 3

What duffy and kidd antibodies are more severe?

Answer 3

> Fy(a) and >Jk(a) are more severe than their counterparts.

Question 4

What maternal factors can increase risk of develping HDFN?

Answer 4

Family history, fetomaternal hemorrhages (C-sec, SAB, external version, amniocentesis), multiple gestations, other exposures, certain HLA types.

Question 5

What titer levels are critical?

Answer 5

> D: 16
K: 8
Others: 32

Question 6

How should the fetus be monitored when maternal antibody titers are significant?

Answer 6

MCA doppler ultrasounds

Sample amniotic fluid for bilirubin

Question 7

How should HDFN be treated?

Answer 7

IUT (if before 35wks of age, else just deliver)

Follow post-partum for jaundice (phototherapy, exchange)