Anti-Fya

Blood Group: Duffy

Common:  34% of caucasians, and 22% of blacks, are Fya- and at risk for developing anti-Fya. The duffy null phenotype is very rare in caucasians but found in 68% of blacks who would be at risk for developing anti-Fya. [5]

Causes HDN: Yes

Critical Titer: 1:16

Information:

HDN due to anti-Fya is uncommon and usually mild. In a study of 68 affected pregnancies, only 3 were severely anemic, and 2 of those required IUTs [2]. In another article, 3 of 18 Fya positive infants required phototherapy, while only one required an exchange transfusion [4]. This stands in contrast to a French infant who required 4 IUTs and an exchange transfusion after birth [7] and a literature review saying that 32% of anti-Fya cases required an exchange transfusion [8]. Additional cases of anti-Fya requiring IUTs have been recorded [9].

Anti-Fya can have a negative direct coombs test in the infant but baby still be affected [1].


As of 2007, Ohio State University concluded that anti-Fya has “the potential to lead to significant fetal hemolysis. Management guidelines developed for D sensitization are appropriate for pregnancies complicated by anti-Fy(a) alloimmunization.” [6]


Articles:

1 - http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1097-0223(199906)19:6%3C533::AID-PD570%3E3.0.CO;2-5/full

2 - http://onlinelibrary.wiley.com/doi/10.1046/j.1365-3148.1997.d01-38.x/full

3 - http://onlinelibrary.wiley.com/doi/10.1111/j.1423-0410.1959.tb04027.x/full

4 - http://www.tandfonline.com/doi/abs/10.3109/00016349509021175

5 - https://www.ncbi.nlm.nih.gov/books/NBK2271/

6 - https://www.ncbi.nlm.nih.gov/pubmed/17880612

7 - https://www.ncbi.nlm.nih.gov/pubmed/1822490

8 - https://www.ncbi.nlm.nih.gov/pubmed/1115167

9 - https://www.ncbi.nlm.nih.gov/pubmed/2604662

10 - https://www.ncbi.nlm.nih.gov/pubmed/885330