Secondary (anamnestic) anti D alloimmunization following transfusion of a DEL phenotype rhesus D negative unit: A case report highlighting the need for DEL screening in India
Year: 2026
Type: article
Study design: Case Report
Abstract: The DEL phenotype is recognized as one of the weakest forms of the D antigen and can be identified through adsorption-elution testing or molecular analysis. At present, routine serologic or genetic screening for DEL variants is not performed among serologically RhD-negative blood donors in India. We describe a rare and clinically significant case of secondary anti-D alloimmunization in an RhD-negative female who developed anti-D antibodies following transfusion of a red blood cell (RBC) unit that was serologically typed as RhD-negative and weak D-negative, but was subsequently confirmed to possess the DEL phenotype. The DEL phenotype represents an extremely weak expression of the D antigen, which often remains undetectable by conventional serologic testing and requires adsorption-elution methods or molecular techniques for definitive identification. To the best of our knowledge, this is the first documented instance from India of anti-D alloimmunization arising specifically from transfusion of DEL phenotype red blood cells.
Institutions: Max Super Speciality Hospital, BLK Super Speciality Hospital
Language: English
Topic: Blood groups and transfusion
Subfield: Hematology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7221057980