Embolization of a Failed Renal Allograft Is Associated with Higher Allosensitization and Worse Graft Outcome in Subsequent Kidney Transplants

Abstract

Introduction: Despite the significant improvement achieved in patient and kidney allograft survival nowadays, an important number of patients return to dialysis showing increased allosensitization and worse graft and patient outcome after receiving a second kidney allograft as compared to the first transplant. Whether removal of the failed allograft by selective embolization or transplant nephrectomy directly influences on allosensitization and subsequent graft outcome is still poorly known. Methods: Herein, in a case control study, we evaluated 62 kidney transplant patients from 2000 to 2010; 31 patients undergoing selective embolization for cause of the failed first allograft (group 1) were compared to 31 patients preserving the first failed organ (group 2). We compared the percentages of panel reactive antibody (PRA) between both groups at baseline (before any transplant), after failure of the first transplant as well as after allograft embolization. Moreover, main clinical outcome when receiving a subsequent second kidney allograft between both groups was also analyzed in a 5-year of mean follow-up. Results: Baseline allosensitization was comparable between both groups (PRA>25%: 6.5%± and 4.8%± for groups 1 and 2, respectively). After failure of the first transplant, patients maintaining the failed organ showed significantly higher allosensitization than patients before undergoing selective embolization (PRA>25%: 25.4%± and 8.5%±, respectively; p=0.029). After allograft embolization, patients showed a significant increased in % of PRA levels than before(19.2% to 46.2%, p=0.09). No differences were found between groups regarding incidence of acute tubular necrosis (ATN), acute rejection (AR) or other main clinical variables. Noteworthy, patients maintaining the failed renal allograft displayed a significantly better graft function evolution at 5 years than patients undergoing selective transplant embolization (eGFR=51,91ml/min and 41.5 ml/min, respectively; p=0.09) Conclusion: Preservation of previous renal failed allografts seems to prevent enhance peripheral allosensitization thus, favouring a better allograft outcome in a subsequent renal transplantation. Our data emphasizes the importance of an accurate immunosuppression management after a failed kidney transplant in order to prevent transplant embolization for cause.