Question

Seven days after the transfusion of 5 red blood cell units, a patient experiences a 5-g/dL decrease in hemoglobin and has mild jaundice. No evidence of bleeding is identified.

1. What tests would provide evidence for a delayed transfusion reaction?

2. What is the rationale for the test selection?

Answer 1

1) Test -- Microscopic examination of recipient blood,, Direct antiglobulin test,,

2)delayed transfusion reaction caused by a secondary immune response to an antigen on donor RBC, if a patient has been immunized long time before ,, the titer of an irregular alloantibody may have decreased so that it cannot be found by antibody screening or cross match during transfusion.

Rationale,,,,, Drawing of blood sample carefully without strong suction. from patient and donor.

Patient and donor pretansfusion sample should also be available for cross match.

Microscopic examination of blood for any incompatibility between donor and recipient blood

If positive then DAT is performed with both blood sample..