The prevalence of the major rhesus antigens in donor blood at the National Blood Transfusion Centre- Nairobi, Kenya
Abstract
Background
In transfusion medicine, the Rhesus blood group system is the most important system
after the ABO blood group. It is relevant in many clinical specialities such as
obstetrics and neonatology as well as general studies such as population and forensics.
It consists of forty nine antigens but only the Rh D antigen is routinely typed in donor
blood. The knowledge of the proportions of these Rhesus antigens is helpful in
determining the Rhesus status and raises interest whenever there are transfusion
related events. This study was therefore undertaken to document the proportion of the
major Rhesus antigens in donor blood units sampled.
Objectives
To determine the prevalence ofthe major Rhesus antigens.
Design
This was a cross sectional, descriptive study.
Setting
The National Blood Transfusion Centre, (Nairobi) Kenya and the Kenyatta National
Hospital haematology laboratory. The study was conducted between July and
September 2010.
Methods
All the blood samples obtained from eligible consenting donors were tested using
standard operating procedures to determine the presence of the Rhesus antigens D, C,
c, E and e. Two different Rh D antisera (Biotec Laboratories Ltd and Fortress
Diagnostics) were used to test the Rh D antigen. Samples that tested negative with
these antisera, were further tested using antihuman globulin and albumin to detect
possible Rh D variants.
Evaluable Parameters
The following parameters were determined and documented; the proportion of donor
blood with the antigens D, C, c, E and e, Rh D variant samples as well as the
proportion of donor blood with various phenotypes of CcDEe, CcDee, ccDEe, ccDee,
ccee, Ccee and CCDee.
Results
Three hundred and sixty (360) donor blood samples were evaluated for Rhesus
antigens and the results were as follows D- 345 (96%), C- 65 (18%), c-356 (99%), E-
68 (19%) and e- 360 (100%). In addition, Rh D variants were detected in 4 (1%) of
samples. Other findings showed that the most common phenotype was ccDee- 224
(62%) while the least common was Ccee -2 (1%).
Conclusions
More than 95% of the donor samples tested were positive for the Rhesus antigens D, c
and e while less than 20% of the samples were positive for the Rhesus antigens C and
E. Only 1% of donor samples had Rh D variants. Majority of donor samples tested
had the phenotype ccDee.
Recommendations
This study recommended that typing of blood donors be done using Rhesus D
monoclonal blend antisera in order to detect possible Rh D variants. In addition,
studies should be done to detect the prevalence of alloantibodies in multiply
transfused patients. This will determine if there is need to establish phenotypic
matching of donor and transfusion dependent recipient.
Citation
Kimani,S.N.,2012.The Prevalence Of The Major Rhesus Antigens In Donor Blood At The National Blood Transfusion Centre- Nairobi, Kenya,A dissertation submitted to the University of Nairobi in part fulfilment for degree of Masters of Medicine in Human Pathology.Publisher
University of Nairobi