Abstract
Pretransfusion tests must detect antibodies that can shorten the life of red blood cells (RBCs). Some studies have demonstrated the existence of clinically significant antibodies detected at 37 degrees C in saline that are not detected by the indirect antiglobulin test (IAT) when the conventional tube test is used. Our aim was to determine whether these antibodies, detected with a 37 degrees C saline tube test, are also detected when a sensitive column gel agglutination method is used. The 2373 pretransfusion samples were tested as they were received (from May 1998 to December 1999), in 37 degrees C saline and by IAT using the DiaMed gel system. The screening tests were performed using 50 microL of 0.8% low-ionic-strength saline suspended RBCs and 50 microL of plasma. The tests were examined for agglutination and hemolysis. Two hundred and thirty three samples (9.81%) were reactive by IAT and 88 (3.70%) by 37 degrees C saline. All 88 samples reactive by 37 degrees C saline also reacted by IAT. These data indicate that 37 degrees C saline is not an essential pretransfusion procedure when the DiaMed gel test is used.