MP31-04 PREDICTING NEW BASELINE GLOMERULAR FILTRATION RATE AFTER DONOR NEPHRECTOMY: VALIDATION OF A SPLIT RENAL FUNCTION BASED FORMULA

Abstract

You have accessJournal of UrologyCME1 Apr 2023MP31-04 PREDICTING NEW BASELINE GLOMERULAR FILTRATION RATE AFTER DONOR NEPHRECTOMY: VALIDATION OF A SPLIT RENAL FUNCTION BASED FORMULA Nicholas Wong, Wei Zheng So, Vineet Gauhar, Benjamin Goh, and Ho Yee Tiong Nicholas WongNicholas Wong More articles by this author , Wei Zheng SoWei Zheng So More articles by this author , Vineet GauharVineet Gauhar More articles by this author , Benjamin GohBenjamin Goh More articles by this author , and Ho Yee TiongHo Yee Tiong More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003264.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Accurate prediction of post donor nephrectomy (DN) glomerular filtration rate is potentially useful for evaluating and counselling of potential living kidney donors. Currently there are limited tools to evaluate the post operative new baseline glomerular filtration rate (NBGFR) in kidney donors. We aim to validate a conceptually simple formula that is based on split renal function (SRF), previously developed for radical nephrectomy (RN) patients (Rathi et al., 2022). METHODS: 83 (mean age 46±12, 44.6% males) consecutive patients who underwent DN (years 2010–2016, 16.9% donated right kidney) with preoperative CT imaging and relevant functional data including baseline Global GFR Pre-DN by CKD-EPI (108.2±13.2mL/min/1.73m2) were included. Observed NBGFR was defined as the latest eGFR 3–12 months post-DN as calculated by CKD-EPI. SRF, defined as volume of the contralateral non-resected kidney normalised by total volume of kidneys, was determined using semi-automated software from preoperative cross-sectional imaging (49.2±2.36%). The equation used was: Predicted NBGFR=1.24 x (Global GFR Pre-DN) x (SRF). Alignment between predicted NBGFR (66.0±8.29mL/min/1.73m2) and observed NBGFR (74.9±16.4mL/min/1.73m2) was assessed by evaluating correlation coefficients, bias, precision, accuracy, concordance and also utilised a Bland-Altman plot to evaluate agreement. RESULTS: The new SRF-based formula for NBGFR prediction correlated strongly with post operative NBGFR (Pearson’s r=0.729, Figure 1) and showed minimal bias (median difference = 7.190mL/min/1.73m2) with good accuracy (96.4% within±30%, 62.7% within±15%) and precision (IQR of bias = -0.094-16.227). The formula tended to underestimate NBGFR values at lower observed NBGFR values and overestimate at higher values. The SRF based formula was also able to accurately discriminate all but one of our patients to a NBGFR of >45ml/min/1.73m2, an NBGFR threshold associated with a reduced risk of renal function deterioration (Campbell et al., 2021). CONCLUSIONS: The newly developed SRF-based formula for predicting NBGFR is validated in a living kidney donor population. This gives clinicians an insight into post operative renal function, granting them better ability to prognosticate, educate and pre-empt DN patients. Source of Funding: There are no sources of funding © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e430 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nicholas Wong More articles by this author Wei Zheng So More articles by this author Vineet Gauhar More articles by this author Benjamin Goh More articles by this author Ho Yee Tiong More articles by this author Expand All Advertisement PDF downloadLoading ...