PLATELET TRANSFUSIONS ARE ASSOCIATED WITH THE DEVELOPMENT OF ANTI-MAJOR HISTOCOMPATIBILITY COMPLEX CLASS-I ANTIBODIES IN PATIENTS WITH LEFT-VENTRICULAR ASSIST SUPPORT

Background: Preformed anti-human leukocyte antigen (HLA) antibodies de lay he,ut transplantation in patients with left ventricular assist dev ices (LVAD) because of difficulty in finding crossmatch-negative donor s. These antibodies may also be associated with adverse outcome after transplantation. Methods: In a retrospective analysis of 40 patients w ith LVAD at Columbia-Presbyterian Medical Center between 1990 to 1996, age, sex, diagnosis, race, duration of support, transfusions, and inf ections were studied by univariate and multivariate analysis as predic tors for development of either anti-HLA class I (anti-I) or anti-HLA c lass II (anti-II immunoglobulin G (IgG) or M (IgM) antibodies. Results : Eighteen (45%) patients had development of anti-I and 20 (50%) had d evelopment of anti-II antibodies over the study period. Median time fo r LVAD support was 142 days (range 35 to 439). Only total number of pe rioperative platelet transfusions predicted the development of anti-I IgG antibodies (p = .04). No other associations were found for develop ment of anti-I IgM or anti-II antibodies of either IgG or Igh I: speci ficity. Patients who had development of anti-I IgG received a mean of 13.9 (SE +/- 2.6) units of platelets compared with a mean of 7.7 (SE /- 2.3) units in those who did not (p = .01). By Kaplan-Meier analysis , at the median duration of follow-up, 8% of patients receiving < 6 un its were predicted to have development of anti-I antibodies compared w ith 63% receiving > 6 units (p = .002). In the last 7 patients, leukoc yte filters were used to decrease the antigenic load during platelet a nd red blood cell transfusions. Only 1 of 7 (14%) patients had develop ment of anti-HLA antibodies compared with 31 of 33 (94%) in whom filte rs were not used (p < .005). Conclusions: These results indicate that platelet transfusion during LVAD implantation is a risk factor associa ted with development of HLA class I IgG antibodies. Use of leukocyte f ilters during platelet transfusion may decrease the risk of developmen t of anti-HLA antibodies.