Serological Detection of Some Rhesus D Polymorphisms among Rhesus Negative Sudanese Blood Donors

Background: Rhesus (Rh) blood group, mainly the D phenotype is subject to polymorphisms associated with several Rh D variants. The identification of such variants may prevent blood reactions due to Rh incompatibilities. Material and Methods: This descriptive cross-sectional study was conducted in Khartoum North, Khartoum-Sudan during the period from December 2021 to March 2022. A total of 100 blood donors who had Rh D negative grouping results were recruited for this study. All samples were tested for weak D and Rh-Del phenotypes by indirect antihuman globulin and adsorption-elution methods respectively. In addition, Rh CE typing was performed for all samples, then the association between Rh CE phenotype and Rh D variants was tested by Chi square test. P values of < 0.05 were considered statistically significant. Results: Among the tested donors, 7% were Rh-Del, 5% were weak D while the remaining 88% were truly Rh-negative phenotype. All Rh-Del subjects were Rh CE positive; 80% of weak D were Rh CE positive, while only 11% of truly Rh-negative donors were Rh CE positive. Statistically significant association was observed between Rh CE positive phenotype with Rh Del and weak D phenotypes, while truly negative Rh D phenotype is associated with negative Rh CE phenotypes (All P values < 0.05). Discussion: Variant D phenotypes were observed in this study population. Therefore, attention for this category among Rh D negative donors is needed to avoid allo immunization in truly negative patients.