Pre-Implantation Kidney Biopsy: Assessing Safety in Transplant Outcomes

Pre-implantation kidney biopsy is commonly used to guide deceased donor organ allocation, despite ongoing controversy regarding its predictive value and potential impact on recipient outcomes. Evidence addressing the safety of this procedure from the recipient's perspective remains limited.

We performed a cross-sectional retrospective study including adult recipients of single deceased-donor renal transplant at Coimbra Local Health Unit between January 2020 and December 2022. Recipients were stratified according to whether the graft underwent pre-implantation biopsy (allocation or zero-time) or not. Early postoperative outcomes included transfusion requirements, hemoglobin variation at 48 hours, primary nonfunction, and cold ischemia time.

Among 257 recipients, 114 (44.4%) received a biopsied graft. Cold ischemia time was slightly longer in biopsied grafts, but not significantly (17.9 vs 16.6 hours; p = .08). Pre-implantation biopsy was not associated with increased transfusion requirements (χ² = 0.475, p = 0.491). In non-transfused recipients, hemoglobin variation at 48 hours was comparable between biopsied and non-biopsied grafts (-21.2% vs -21.1%; p = .990). Rates of primary nonfunction (p = .518) did not differ significantly between groups. Two early postoperative deaths occurred in recipients of biopsied grafts, neither related to the biopsy procedure.

In our cohort, pre-implantation renal graft biopsy was not associated with worse early postoperative outcomes. These findings support the safety of selectively performed procurement biopsies in kidney transplantation practice.