Purpose: We assessed the change in remaining kidney function after laparoscopic donor nephrectomy using serial technetium 99m diethylenetriaminepentaacetic acid (DTPA) scans and investigated the factors affecting the course.
Methods: Data from 155 donors were obtained from a prospectively maintained database. All donors underwent consecutive DTPA scans preoperatively and 1 month, 6 months and 1 year postoperatively. We investigated the longitudinal change in renal function after surgery and analyzed parameters to influence the perioperative glomerular filtration rate (GFR) change.
Results: The changes in GFR according to the DTPA scan presented significant improvement from 1 month up to 2 years after donation (all p < 0.001). The DTPA-GFR of the remaining kidney increased by 14.8% to 58.2 ± 10.6 ml/min/1.73 m(2) (p < 0.001) and by 33.9% to 78.0 ± 14.0 ml/min/1.73 m(2) at 1 month and 1 year after surgery, respectively (p < 0.001). Only 21.9% of donors categorized into chronic kidney disease (CKD) stage 3 or more at 1 year after donation were <60 ml/min/1.73 m(2) according to DTPA-GFR. Multivariate regression analysis revealed that the increase in DTPA-GFR at 1 year was negatively associated with patient age (p = 0.005), BMI (p = 0.04) and preoperative DTPA-GFR of remaining kidney (p = 0.009).
Conclusions: The DTPA-GFR of remaining kidney increased steadily for up to 2 years after surgery. Younger donors with lower body mass index and those with lower initial function of the remaining kidney demonstrated a greater increase in DTPA-GFR after nephrectomy. Many of the donors with CKD stage 3 after donation have good renal function according to the results of DTPA-GFR.