Lack of alloimmunization to the D antigen in D negative orthotopic liver transplant recipients receiving D positive rbcs perioperatively
Wlosinski L, El-Bashir J, and Otrock ZK. Lack of alloimmunization to the D antigen in D negative orthotopic liver transplant recipients receiving D positive rbcs perioperatively. Transfusion 2018; 58:44A-45A.
Background/Case Studies: D negative (D-) patients (pts) are routinely transfused with D-RBCs due to the increased immunogenicity of the D antigen. The rate of alloimmunization to the D antigen following transfusion can be as high as 80%; however, immunosuppressed pts may be less likely to become alloimmunized. Some D-pts undergoing liver transplant may require a large number of RBC units which can risk the inventory of D-RBCs which are considered relatively rare (10-15% of donor units) as compared to D positive (D+) RBCs. So the blood bank may be forced to supply such pts with D + RBCs due to inventory constraints. Though the process of providing D +RBCs to D-transplant recipients is accepted in blood bank practice, the incidence of alloimmunization to the D-antigen in D-liver transplant pts has not been well defined. With a very active liver transplant program at our institution, studying the prevalence of anti-D formation in D-liver transplant pts receiving D + RBCs perioperatively will assist in successful patient blood management. Study Design/Method: This was a retrospective study performed at a single large academic medical center. The study was approved by our Institutional Review Board. Electronic medical records and blood bank files for all 505 pts who underwent orthotopic liver transplantation at Henry Ford Hospital in Detroit, Michigan, from August 2012 through December 2017 were reviewed. Results/Finding: Twelve D-pts received D +blood perioperatively. Table 1 summarizes the characteristics of these pts. The median age was 60 years (range 48-67 years); 8 (66.7%) were male. Median number of D + RBC units transfused was 13.5 units (range 3-72 units). There was no evidence of D alloimmunization in any patient after a median follow up of 30.9 months (range 20.2-59.6 months). Only one patient died after surgery. We had 8 D-pts (8/76 = 10.5% of all D-liver transplant recipients) who presented with D alloimmunization before transplant; none of these pts was transfused with D + blood at our institution. Conclusion: Our study showed that there was no risk of alloimmunization to the D antigen in D-orthotopic liver transplant recipients receiving D + RBCs perioperatively.