Investigating discrepancies and false positives in immunohematology tests using gel cards: insights from a case study on antibodies targeting the gel card matrix

The false-positive reactions were attributed to antibodies against materials in Tulip gel cards, including silica-based microbeads, polyvinyl alcohol, and other stabilizers that are absent in Bio-Rad gel cards. This case underscores the importance of multiplatform validation, reagent standardization, and conventional tube testing in resolving immunohematologic discrepancies and ensuring safe transfusion practices.