Delayed hemolytic transfusion reaction by a Kidd antibody after heart surgery: case report and review of the literature.

Delayed hemolytic transfusion reactions (DHTRs) usually occur between 3 and 14 days after transfusion as a result of a secondary immune response, with a drop in hemoglobin level, fever, jaundice, or hemoglobinuria. There is no sure means of avoiding DHTR completely, even with the application of the most sophisticated methods. Kidd system antibodies are difficult to detect because they often show a great deal of serologic variability and weak in vitro expression. They have been reported to cause severe immediate or delayed hemolytic transfusion reactions. We present a case of DHTR resulting from anti-Jka after cardiac surgery, and we report the observed changes in the pattern of occurrence of DHTRs.