Identification of alloimmunized patients: use of radiolabeled allogeneic
platelet kinetic measurements and platelet antibody tests
WI Bensinger, J Hadlock and SJ Slichter
Fred Hutchinson Cancer Research Center, Seattle, WA 98104.
In a group of stable, nonthrombocytopenic leukemia patients awaiting bone
marrow transplantation, results of paired allogeneic radiolabeled platelet
kinetic measurements were correlated with the results of several different
platelet and lymphocytotoxic antibody tests to determine which parameters
could be used to identify patients who were alloimmunized to platelets.
Seven patients with acute leukemia who had been transfused during induction
therapy were used as the test group, and, as a control group, five
untransfused patients with chronic myelogenous leukemia were also studied.
Concurrent fibrinogen survival measurements were performed in all patients
to assess whether hemostatic factor consumption (ie, disseminated
intravascular coagulation) was present. Allogeneic platelet survival
measurements were reduced from normal in all 12 study patients. In 8 of 12
patients, fibrinogen and platelet survival measurements were comparably
reduced, suggesting disease-related platelet consumption. In four heavily
transfused patients with acute leukemia, allogeneic platelet survivals were
markedly reduced to less than or equal to 2.1 days, compared with the 3.5-
to 7.4-day platelet survival measurements found in the other eight
patients. The disproportionately short platelet survivals compared with
fibrinogen survival measurements in these four patients, combined with
documented positive antibody tests to their donors' platelets in the three
patients with evaluable tests, suggested that these patients had become
alloimmunized to platelets because of their prior transfusions. There was
substantial concordance between the two radiolabeled allogeneic donor
platelet survival measurements performed in each of these patients,
suggesting that host rather than donor factors have a major influence on
transfusion outcome (r = .93, P less than .001). The platelet cross-match
tests, using the radiolabeled protein Staph A assay combined with the IgG
enzyme-linked immunosorbent assay test, had the best correlation with the
posttransfusion recovery and survival of the donors' platelets.
Volume 77,
Issue 11,
pp. 2372-2378,
06/01/1991
Copyright © 1991 by The American Society of Hematology