Identification of previous erythrocyte alloimmunization and the type and screen at a large cancer center. A 4-year retrospective review.

A review of 4 years of hemolytic transfusion reactions and evidence for erythrocyte alloimmunization (RBC-A) was conducted from September 1, 1985 to August 31, 1989 to assess retrospectively the safety of pretransfusion testing using the type and screen (T & S) with immediate-spin crossmatch (IS-XM). All transfusion reaction reports were reviewed for reported "possible hemolytic transfusion reaction" and RBC-A, as identified by the reviewing pathologist. Three hemolytic transfusion reactions (HTR) and eight RBC-A were found for the 4 years. During the review period, 92,759 units of packed RBC were transfused to 22,317 patients. Of these, 76,257 (82.2%) units of packed RBC had IS-XM, 12,414 (13.4%) had an antiglobulin crossmatch, and 4088 (4.4%) were issued without crossmatch. Of the immediate reactions, two were caused by clerical errors, and one was of undetermined cause. The eight RBC-A were discovered during subsequent pretransfusion testing in the Transfusion Service and classified as anamnestic responses to prior transfusions or pregnancies. The eight RBC-A were attributed to the following antibodies: three anti-Jka, one anti-E, one anti-FYa plus unidentified antibody, one anti-Fya, one anti-Jkb, and one anti-Fy3. The low rate of HTR and prior RBC-A detected posttransfusionally in a large cancer center such as this may be used to support the conclusion that the use of T & S with IS-XM is a reasonably safe procedure.