Change in renal parenchymal volume in living kidney transplant donors.

Purpose: Uninephrectomy would induce compensatory hypertrophy in the remaining kidney. We investigated the relationship between changes in renal parenchymal volume (RPV) and renal function after nephrectomy in living kidney donors.

Methods: From July 2011 and January 2012, 45 kidney donors were enrolled in this study. Magnetic resonance scanning was performed before surgery, 3 and 7 days postoperatively, and RPV was calculated through disc summarize methods. Participants were followed up for 1 year.

Results: The RPV of the remaining kidney was 118.06 ± 23.51 cm(3) and then increased by 21.23 % to 143.13 ± 25.52 cm(3) at 3 days and by 24.17 % to 146.60 ± 25.86 cm(3) at 7 days. Multivariate regression analysis showed that preoperative RPV is positively related to its initial function (p = 0.037); the RPV at 7 days is directly related to its initial, preoperative size (p < 0.001). With respect to change in postoperative RPV, there is bigger gain in size in smaller kidneys (p = 0.005). The kidneys that has ≥20 % increase RPV after 7 days are more likely to show further increase in GFR at 1 year (p = 0.024).

Conclusions: Uninephrectomy induced immediately increment in RPV of the remaining kidney. Donors with RPV increase of ≥20 % at 1 week have a more favourable renal function adaptation at 1 year.