DELAYED HEMOLYTIC TRANSFUSION REACTION DUE TO ANTI-JS(A) IN AN ALLOIMMUNIZED PATIENT WITH A SICKLE-CELL SYNDROME

Delayed hemolytic transfusion reactions occur via an anamnestic immune response in patients previously alloimmunized by certain RBC antigens . Conventional pretransfusion antibody screening tests and crossmatche s are unable to detect certain antibodies that potentially can cause t hese reactions because they may be present in low concentrations or ha ve low affinity for their respective antigen or their indicator antige n may be absent from test RBCs. We report the second case of a delayed hemolytic transfusion reaction caused by an undetectable (by routine methods) anti-Js(a) in a patient with a sickle cell syndrome (hemoglob in SC disease) and multiple alloantibodies, in whom retrospective indi rect antiglobulin tests enhanced by polyethylene glycol revealed the p resence of weakly reactive anti-Js(a).