RhD negativity among pregnant women in multiethnic Suriname

Predeposit Autologous Blood Donation in Rh(D)-Negative Pregnant Women: A Single-Center Study

Objective  The primary purpose of this study was to assess the practicability of predeposit autologous blood donation (PABD) in the practice of Rh(D)-negative pregnant women. Materials and Methods  A cohort of 405 Rh(D)-negative pregnant women who had a delivery in the comprehensive tertiary hospital in Nanjing was analyzed retrospectively, over 10 years. Results  After PABD, 203 women experienced a slight drop in mean hemoglobin of 5.32 ± 0.5 g/L (PABD-associated anemia was not featured in our study). Thirteen women who received allogeneic blood might benefit from PABD practically. Conclusion  PABD is applicable for Rh(D)-negative pregnant women, as it ensures the availability of the patient's blood in the event of perinatal hemorrhage, thus minimizing the need for transfusion from external sources. Despite the autologous blood reinfusion of low proportion, PABD could still serve as an alternative when allogeneic blood resources are scarce. However, one challenge in the future is to identify candidates who may benefit most from PABD. Also, more attention is needed to raise awareness of patient blood management. Recommended strategies include early screening and treatment of anemia, hemostasis promotion, and blood loss reduction. Replacement of allogeneic transfusion with autotransfusion could be referred to where feasible. We believe that PABD still has a promising potential for application in Rh(D)-negative pregnant women.

Frequency and characterization of RHD and RHCE variants in the Noir Marron population from French Guiana

BACKGROUND

The RH system is one of the most polymorphic blood group systems due to the proximity and opposite orientation of RHD and RHCE genes. Numerous alleles are described and can affect Rh protein expression. This complexity is especially evident in populations of African origin. We performed RHD and RHCE genotyping of the Noir Marron population in French Guiana. This population belongs to the Maroon community who are direct descendants of African slaves, who escaped from Dutch plantations, in the current day Suriname, during the 17th century. They represent an original ethnic group with highly blended culture.

METHODS AND MATERIALS

A total of 89 DNA samples were collected from four different ethnic groups of the Noir Marron population of French Guiana. RHD and RHCE genotyping was performed using DNA microarray and/or sequencing.

RESULTS AND DISCUSSION

Significant allelic diversity was shown, with 45% of individuals presenting an RHD gene variant (most common: RHD*DAU, RHD*DIVa, and RHD*DIIIa allele) and 9.4% with a partial D phenotype. Likewise, 85% presenting an RHCE gene variant and 9% a partial RH2 antigen. One original allele was identified in two D+ Noir Marron individuals: a hybrid RHD*DIIIa-CE(9)-D allele, encoding probably a partial D antigen and associated with an RHCE*ce(48C,733G,1006T) allele. The African diversity of RHD and RHCE genes is found in this population with preserved genetic but mixed cultural backgrounds. These data allow us to describe the characteristics of the RH system antigen and highlights a significant number of partial antigens with a risk of alloimmunization.

Frequency and characterization of RHD variants in serologically D- Surinamese pregnant women and D- newborns

BACKGROUND

Numerous RHD variant genes affect the expression of D on the red blood cell surface. In Suriname, 4.3% of pregnant women were D-, ranging from virtually zero to 7% among ethnic groups. Characterization of RHD variants, which are associated with a variable potential to induce anti-D, is of practical clinical importance especially in case of limited access to preventive measures. Here we report on the occurrence of RHD variant genes in Surinamese serologically D- pregnant women and their D- newborns from different ethnic groups.

STUDY DESIGN AND METHODS

The RheSuN study is a cross-sectional cohort study in D- pregnant women and their newborns, who visited hospitals in Paramaribo, Suriname, during routine pregnancy care. The presence of RHD variants was investigated using quantitative polymerase chain reaction targeting RHD Exons 5 and 7 and RH-multiplex ligation-dependent probe amplification.

RESULTS

Seven RHD variant genes were detected in 35 of 84 women and four RHD variant genes in 15 of 36 newborns. The RHD*03 N.01 and RHD*08 N.01 variants represented 87% of a total of 62 variant genes. Variants were comparably frequent among ethnicities. In four cases genotyping would have changed anti-D prophylaxis policy: one woman with a RHD*01EL.01 variant, not associated with anti-D formation and three D- newborns with RHD*09.01 and RHD*09.03.01 variants, potentially capable of inducing anti-D.

CONCLUSION

RHD variants at risk for anti-D are common among serologic D- individuals from African descent in Suriname. While genotyping D- women has limited added value, it may be considered in newborns from D- women.