Objectives: Delayed graft function is a significant prognostic indicator after renal transplantation. We hypothesized that delayed graft function is not a single entity, and different patterns of delayed graft function reflect various underlying pathological processes.
Materials and methods: An analysis of 762 renal transplants was performed, showing serum creatinine was charted serially for the first 30 days after transplant. Measurements were obtained: time on hemodialysis; time to peak creatinine; time for creatinine to half; time for creatinine to within 10% of baseline.
Results: Four patterns of delayed graft function were identified. There was no association between pattern of delayed graft function, and 1-year graft survival or serum creatinine at 1 year. Time for creatinine to > 15 days was associated with a higher creatinine level at 1 year than it was with patients with time for creatinine to half < 5 days (300.6 ± 54.3 vs 211.3 ± 26.0 μmol/L; P < .01). Patients with 1-year creatinine concentrations > 180 μmol/L had longer time on hemodialysis and time for creatinine to half than did those with 1-year creatinine concentrations ≤ 180 μmol/L (9.2 ± 1.3 μmol/L vs 7.0 ± 0.7 μmol/L; P = .03; and 11.6 ± 1.7 μmol/L vs 6.0 ± 0.4 μmol/L; P < .001). Time for creatinine to half of 6.5 days (sensitivity 67.3%; specificity 79.4%; area under the curve, 0.70) was the best predictor of a 1-year creatinine concentration ≤ 180 μmol/L.
Conclusions: Delayed graft function is not a single entity; rather; it is the most common presentation of a heterogeneous variety of pathologies. Its rate of resolution of renal function is the best predictor of long-term graft outcome.