Introduction:
The hypothesis is that transplanting a greater nephron mass would reduce glomerular hypertension and hyperfiltration, thereby increasing graft survival. Therefore, in this study, to further investigate the impact of donated kidney volume on the estimated GFR of the recipient at 1 year post-transplantation and adjust kidney volume for the size of the recipient, we calculated the ratio of donor kidney volume (DKV) to recipient body surface area (BSA). BSA of the recipient was used as a surrogate marker for metabolic demands of the recipient.
Methods:
We conducted an observational prospective study at our institute involving 130 renal transplant recipients (August 2022 to July 2023). Only recipients of living kidney donors above 18 years were included. Donor kidney volume was quantified using three-dimensional computed tomography angiography (CTA), adjusted to recipient BSA to calculate DKV/BSA. Recipients were stratified into four groups based on ascending DKV/BSA values. Follow-ups occurred at 3, 6, and 12 months post transplantation, focusing on eGFR and rejection rates.
Results:
Groups differed significantly in DKV/BSA values between Group 1 and Group 4. (Group 1: mean 48.22, SD 3.83; Group 4: mean 84.16, SD 11.6). Baseline eGFR of donors did not vary significantly among groups (Group 1: mean 105, SD 7.1; Group 4: mean 104, SD 10.1). A significant difference in mean eGFR at 1 year was noted between groups. (Group 1: 59.75, SD 18; Group 4: 77.2, SD 17; p < 0.05), Table 1. When all groups were compared with each other for eGFR values at 1 year post transplantation, then group 1 has statistically significantly low GFR when compared to groups 2, 3, and 4. While a statistically significant difference in P value was not seen when groups 2, 3, and 4 were compared with each other for 1 year eGFR, Table 2. Rates of rejection and urine protein creatinine ratio (UPCR) did not differ significantly between the groups.
Table 1 Overview of Graft function (eGFR) over 1 year
Table 2 Comparison of eGFR at 1 year between the groups :
Conclusions:
This study highlights the potential predictive value of DKV/BSA in recipient kidney function outcomes post transplantation. Higher DKV/BSA correlated with better eGFR at 1 year. In our data, we observed that Group 1 has a significantly low GFR at 1 year, where the maximum donor kidney volume for Group 1 recipients was 86 ml. So we concluded from our study that recipients who were transplanted with DKV less than 86 mL did not do well in terms of the eGFR of the recipient at 1 year post transplantation, and those recipients with DKV more than 86 had no statistically significant difference in eGFR at 1 year. Incorporating preoperative kidney volume assessments into donor-recipient matching algorithms may optimize renal mass transfer and improve transplant outcomes. Further research in larger cohorts is warranted to refine clinical practices and enhance long-term graft survival.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.