Predonation Single Kidney Glomerular Filtration Rate in Living Kidney Transplantation to Predict Graft Function and Donor Functional Gain

Background: The 2 main objectives regarding living kidney transplant are to provide optimal graft function and to ensure the safety of donation. Our study hypothesized that the glomerular filtration rate of a single kidney (skGFR), when transplanted, might predict graft function and that the skGFR of the remaining kidney could predict donor functional gain.

Methods: A prospective monocentric study was conducted at Grenoble-Alpes University Hospital. Twenty couples of donors and recipients were included. Dimercaptosuccinic acid renal scintigraphy and ⁵¹Cr-ethylene-diamine tetra-acetic acid clearance were evaluated predonation to calculate skGFR. All patients had renal function according to ⁵¹Cr-ethylene-diamine tetra-acetic acid clearance at 1 year post transplant to assess graft function and donor functional gain. All donors had normal renal function predonation.

Results: At 1 year post transplant, median glomerular filtration rate of the graft was 50 mL/min/1.73 m² (range, 46-56 mL/min/1.73 m²) and donor median glomerular filtration rate was 59 mL/min/1.73 m² (range, 55-74 mL/min/1.73 m²). Median functional gain was 20 mL/min/1.73 m² (range, 12-22 mL/min/1.73 m²). No statistical correlation was found between skGFR of the transplanted kidney and graft function at 1 year (R² = 0.096, P = .7). For the donor, functional gain was not associated with predonation skGFR of the remaining kidney (R² = 0.17, P = .5). A statistical difference was found between donor functional gain (18 [SD, 10] mL/min) and recipient gain (delta between skGFR before and after transplant, 7 [SD, 16] mL/min; P = .02).

Conclusion: Predonation skGFR of the transplanted kidney had no influence on renal allograft function at 1 year post transplant. Similarly, there was no association between measured skGFR of the remaining kidney and donor functional gain at 1 year.