Protocol Biopsies in Delayed Graft Function Kidney Transplants From Brain-Dead Donors.

Area of Science:

• Nephrology
• Transplant Surgery
• Immunology

Background:

• Delayed graft function (DGF) affects one-third of deceased donor kidney transplant recipients, increasing acute rejection risk.
• Current guidelines recommend sequential protocol biopsies for DGF kidneys, based on older immunosuppression data.
• Decreasing acute rejection rates necessitate re-evaluating the utility of routine post-transplant protocol biopsies.

Purpose of the Study:

• To assess the diagnostic yield of sequential protocol biopsies in the first month post-transplant for deceased donor kidney recipients with DGF.
• To determine the incidence and timing of acute rejection episodes in DGF kidneys under modern immunosuppression protocols.
• To re-evaluate the clinical relevance of protocol biopsies in the context of current immunosuppression strategies.

Main Methods:

• Retrospective analysis of 1022 protocol biopsies from 678 deceased donor kidney recipients with DGF (2006-2023).
• All recipients received corticosteroid induction; some received anti-thymocyte globulin or basiliximab.
• Histological review of biopsies taken within the first month post-transplant.

Main Results:

• 178 out of 678 recipients (26%) experienced acute rejection, predominantly within 7-10 days post-transplant.
• In cases with no rejection on the first biopsy, subsequent biopsies revealed rejection in 10% of cases.
• Donor-specific antibodies were linked to higher rates of antibody-mediated rejection (20% vs. 1.3%).

Conclusions:

• The initial post-transplant biopsy is vital for detecting early acute rejection in DGF kidneys.
• Rejection occurred in only 10% of DGF kidney transplants without rejection in the first biopsy.
• Borderline findings on biopsy progressed to rejection in approximately one-third of cases, highlighting their significance.