Time-Zero Kidney Biopsy and Deceased-Donor Transplant Outcomes: A Systematic Review and Meta-Analysis of Prognostic Value, Prediction, and Clinical Utility.

Background/Objectives: Time-zero biopsy informs deceased-donor kidney implantation or discard, but its prognostic value is contested. We systematically reviewed pre-reperfusion morphological biopsy evidence in adult deceased-donor kidney transplantation, keeping four questions separate: prognostic association, incremental prediction, clinical utility and measurement reproducibility. Methods: We searched PubMed/MEDLINE, Embase, Scopus, Web of Science, CENTRAL and three trial registries through 25 July 2026 without date or language restriction. One estimate per non-overlapping cohort was selected under a prespecified hierarchy; random-effects models used restricted maximum likelihood with Hartung-Knapp inference; GRADE assessed certainty. Results: Of 45,676 records, 25,746 were screened; 203 eligible reports (159 study investigations and 154 cohort families) and 22 contextual reports were included. Vascular injury was associated with delayed graft function (odds ratio: 1.85, 95% CI 1.11-3.06), glomerulosclerosis with graft failure (hazard ratio: 2.03, 1.22-3.39) and vascular injury with graft failure (hazard ratio: 1.48, 1.07-2.04); glomerulosclerosis with delayed graft function was inconclusive (odds ratio: 1.13, 0.59-2.17). All 12 pooled bodies were of very low certainty. Conclusions: Current evidence does not support time-zero histology as a stand-alone rule for accepting or discarding a deceased-donor kidney. Whether standardized histology adds predictive information beyond established clinical variables remains open and should be addressed in linked registry analyses before biopsy findings guide management.