The impact of measuring split kidney function on post-donation kidney function: A retrospective cohort study

Abstract

Background Studies have reported agreement between computed tomography (CT) and renography for the determination of split kidney function. However, their correlation with post-donation kidney function remains unclear. We compared CT measurements with renography in assessment of split kidney function (SKF) and their correlations with post-donation kidney function. Methods A single-centre, retrospective cohort study of 248 donors from January 1, 2009-July 31, 2019 were assessed. Pearson correlations were used to assess post-donation kidney function with renography and CT-based measurements. Furthermore, we examined high risk groups with SKF difference greater than 10% on renography and donors with post-donation eGFR less than 60 mL/min/1.73m2. Results 62% of donors were women with a mean (standard deviation) pre-donation eGFR 99 (20) and post-donation eGFR 67 (22) mL/min/1.73m2 at 31 months of follow-up. Post-donation kidney function was poorly correlated with both CT-based measurements and renography, including the subgroup of donors with post-donation eGFR less than 60 mL/min/1.73m2 (r less than 0.4 for all). There was agreement between CT-based measurements and renography for SKF determination (Bland-Altman agreement [bias, 95% limits of agreement] for renography vs: CT volume, 0.76%, -7.60–9.15%; modified ellipsoid,1.01%, -8.38–10.42%; CC dimension, 0.44%, -7.06–7.94); however, CT missed SKF greater than 10% found by renography in 20 out 26 (77%) of donors. Conclusions In a single centre study of 248 living donors, we found no correlation between CT or renography and post-donation eGFR. Further research is needed to determine optimal ways to predict remaining kidney function after donation.

Whole and cortical kidney volume predict 5‐year post‐nephrectomy eGFR in Indian living kidney donors

“…Predicting 5yeGFR Cr and identifying donors who are unlikely to adapt appropriately to nephrectomy are useful tools to inform donor selection, which can be incorporated into management algorithms by Indian transplant physicians. The long duration of follow up (which was uniform for all donors), sets this study apart from previous CT volumetry studies in Caucasian and South‐East Asian LKD cohorts with post‐nephrectomy function having been measured at periods varying from 3 days 13 to 2.5 years 37 . The routine measurement of pre‐nephrectomy cystatin C eGFR allowed us to demonstrate that it may be more representative of nephron mass than creatinine eGFR, which has important implications for LKD evaluation.…”

“…9 In LKDs who may be at particular risk for sub-optimal adaptation, for example older LKDs, rCKV may offer a benefit over rWKV, Asian LKD cohorts with post-nephrectomy function having been measured at periods varying from 3 days 13 to 2.5 years. 37 The routine measurement of pre-nephrectomy cystatin C eGFR allowed us to demonstrate that it may be more representative of nephron mass than creatinine eGFR, which has important implications for LKD evaluation.…”