Red blood cell antigen alloimmunization in liver transplant recipients

Orthotopic liver transplantation (OLT) is a life-saving procedure for patients with end-stage liver disease. Transfusion support is an important part of OLT. Intraoperative transfusion of large volumes of blood products is recognized to be a poor prognostic factor, probably due to the negative effects of blood transfusions, such as transfusion reactions, infectious contamination of blood products, or immune modulation of the transfused patient. The aim of this study was to evaluate the frequency of alloimmunization and its specificity to red blood cell (RBC) antigens among patients undergoing OLT. We identified 74 RBC alloantibodies in 70 (23%) patients when the indirect antiglobulin test (IAT) was performed. The most common RBC alloantibodies were against Rh system antigens. The majority (41.9%) were directed against the E antigen. Despite the ethnic heterogeneity of our population there were no cases of intravascular hemolysis. The incidence of alloimmunization (23%) was slightly higher among patients than in the literature, most probably as a consequence of our ethnic heterogeneity.