Potential risk factors for hypersensitization reflected by panel-reactive antibodies in dialysis patients

Abstract

Introduction: The panel-reactive antibody (PRA) test has been considered to be a routine index of sensitization to human leukocyte antigens (HLA) in kidney transplant candidates. This study investigated the effect of potential risk factors and the time of blood sampling on PRA tests.

Methods: A total of 98 patients at two dialysis centers in Tehran were tested for PRA levels before and after dialysis sessions. We evaluated their history of potential sensitizing events and patient interviews for their association with PRA levels. Also we compared PRA levels obtained before and after dialysis.

Results: The mean age of the patients was 58.33 +/- 15.85 years. Only age and kidney transplantation history were correlated with PRA levels (r = .246, P = .014 and P = .0001, respectively). Logistic regression analysis revealed an association between age and PRA level (P = .037). Transplantation history was weakly correlated with PRA level (P = .076). History of pregnancy and transfusion, dialysis duration, gender, donor relation, and kidney allograft duration were not associated with PRA. PRA before dialysis sessions was significantly lower than that after dialysis (P = .0003). However, no difference was seen when divided into groups of negative/positive (PRA < 10% as negative) and high/low (PRA < 60% as low).

Conclusion: Many factors expose patients to HLA as sensitizing factors. However, it seems that PRA level is not always predictable by such conditions. Furthermore, dialysis as a confounding procedure impacts PRA results; thus, when to obtain a blood sample is a crucial question.