Design: Systematic review and random-effects meta-analysis
Population: 203 reports on adult deceased-donor kidney transplants
Primary outcome: Delayed graft function and graft failure by time-zero histology
Effect: Glomerulosclerosis–graft failure HR 2.03 (95% CI 1.22–3.39); all very low certainty

This large systematic review included 203 reports on pre-reperfusion biopsy in adult deceased-donor kidney transplantation, separating four questions: association with outcome, added prediction, clinical utility and reproducibility.

Vascular injury was associated with delayed graft function (OR 1.85, 95% CI 1.11–3.06) and graft failure (HR 1.48, 1.07–2.04). Glomerulosclerosis was associated with graft failure (HR 2.03, 1.22–3.39) but inconclusively with delayed graft function. All 12 pooled estimates were rated very low certainty.

Association is not the same as useful prediction. The review found no reliable evidence that biopsy adds to established clinical donor and recipient variables, so using a biopsy score as a stand-alone discard rule risks throwing away usable kidneys.

Do not use time-zero biopsy findings alone to discard a deceased-donor kidney.
Combine histology with donor age, kidney function, cold ischaemia time and recipient factors.
Expect variability in how biopsies are read, especially on frozen sections out of hours.
Advocate for registry studies that test whether biopsy adds to clinical risk scores.

Why it matters

Unjustified discards waste organs in a system where every kidney counts.

The statistics, in plain English

Hazard and odds ratios show that damaged kidneys do worse on average, but 'very low certainty' means the true effects may differ substantially. A marker can be associated with outcome and still add little to predicting it once other factors are known.