A Study to Determine the Prevalence of Weak D in Donors and Patients at a Tertiary Care Teaching Hospital in Telangana

Introduction: The Rhesus (Rh) blood group system is considered the next most important after ABO. It is of clinical significance in regard to transfusion and pregnancy. The Weak D phenotype (Du)is a weakened form of D antigen that cannot be detected by routine grouping (using immediate spin tube methodology). 
Aims: 
1) To determine the prevalence of weak D. 
2) To assess the implications in terms of alloimmunization. 
3) To provide knowledge on the weak D status and enhance the importance of weak D determination in the donor and patient population. 
Study Design: A retrospective study. 
Place and Duration of Study: Licensed blood bank in Malla Reddy Narayana Multispecialty Hospital under Department of Pathology, data from blood bank records was collected from 1st of August 2018 to 31st of July 2019. 
Methodology: It was a one-year study at a tertiary care centre and study group included both donors and patients who were admitted and those attending outpatient departments who were identified for blood grouping test at the blood bank. Data was collected from the blood bank records. 
Results: A total of 4054 blood samples were analysed out of which of 3405 were Rh D positive and 649 samples were RhD negative. On further testing 12 out of 649 Rh D negative, were found to be weak D positive. 
Conclusion: For a safer transfusion and to prevent alloimmunisation it is recommended to develop protocols for weak D testing for the individuals who are Rh D negative on routine testing in regions showing significant prevalence.