Sharing information today to save the lives of tomorrow.
Isoimmunization: An Intro to Antibodies in Pregnancy
Empowering women to be partners in their prenatal care.
Sharing information today to save the lives of tomorrow.
Sharing information today to save the lives of tomorrow.
Anti-B
Blood Group: ABO
Common: Yes, especially among blacks. 62.7% of black type O people have anti-B
Causes HDN: Yes
Critical Titer: 1:16
Information:
One of the important things to note is that there is a difference in the severity of HDN based on race. HDN due to anti-A or anti-B is more severe in blacks and latinos than in whites [2, 3]. It is possible to have both anti-A and anti-B at the same time [7]. It is especially important that black infants are not discharged from the hospital prematurely and without proper follow up when ABO incompatibility is suspected. It has been suggested that a 6 hour bilirubin can determine the risk for significant hyperbilirubinemia (4 mg/dL) or severe HDN (6 mg/dL) due to ABO incompatibility [1].
ABO HDN remains the most frequent cause of severe and early jaundice in newborns [4]. Treatments include exchange transfusion and IVIG in addition to phototherapy. Exchange transfusion can lead to a 44.03% reduction in indirect bilirubin [6]. IVIG can reduce the need for exchange transfusion [4, 5]. One study suggests that maternal titers >1:512 can be good predictors of the need for IVIG and exchange transfusion [8], while another study says that titers aren’t useful in predicting the need for exchange transfusion [9].
In general HDN from Anti-B is viewed as being more severe than anti-A. This is because severe HDN due to anti-B is seen more frequently than severe HDN due to anti-A, however anti-A can cause severe HDN too. [10]. Another study said that anti-A and anti-B occur with almost the same frequency and there is no difference in severity [11].
There are multiple reports of severe HDN due to anti-B [12, 13, 14, 15]. While rare, anti-B can affect baby in utero and is capable of causing hydrops [14] and fetal distress requiring emergency c section [12, 13]. Anti-B can also affect baby after birth and cause severe anemia within hours [14, 15].
Articles:
1 - https://www.ncbi.nlm.nih.gov/pubmed/11927726
2 - https://www.ncbi.nlm.nih.gov/pubmed/7117940
3 - https://www.ncbi.nlm.nih.gov/pubmed/856960
4 - https://www.ncbi.nlm.nih.gov/pubmed/25125032
5 - https://www.ncbi.nlm.nih.gov/pubmed/15590442
6 - https://www.ncbi.nlm.nih.gov/pubmed/8284577
7 - https://www.ncbi.nlm.nih.gov/pubmed/18793871
8 - https://www.ncbi.nlm.nih.gov/pubmed/19703120
9 - https://www.ncbi.nlm.nih.gov/pubmed/1082679
10 - https://www.ncbi.nlm.nih.gov/pubmed/11508073
11 - https://www.ncbi.nlm.nih.gov/pubmed/22595217
12 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1720779/pdf/v078p0F220.pdf
13 - https://www.ncbi.nlm.nih.gov/pubmed/1923220
14 - https://www.ncbi.nlm.nih.gov/pubmed/15713130
16 - https://www.ncbi.nlm.nih.gov/books/NBK2267/