Which of the following blood group antigens is most commonly associated with delayed hemolytic transfusion reactions?

A RhD antigen
B Kell antigen ✓
C Duffy antigen
D Jk^a antigen

Explanation

The Kell antigen is a common cause of delayed hemolytic transfusion reactions due to its immunogenicity and the potential for anamnestic responses.

Source

Transfusion Medicine journal
Hematology Hematology: Blood Grouping and Crossmatching Hematology: Blood Grouping and Crossmatching Hard MEDICAL Confidence: medium