Predicting new-baseline glomerular filtration rate (NBGFR) after donor nephrectomy: validation of a split renal...

Area of Science:

• Nephrology
• Urology
• Surgical Outcomes

Background:

• Predicting post-donor nephrectomy (DN) glomerular filtration rate (GFR) is crucial for living kidney donor evaluation and counseling.
• Limited tools currently exist for estimating new-baseline GFR (NBGFR) after DN.
• This study validates a formula based on split renal function (SRF) for NBGFR prediction.

Purpose of the Study:

• To validate a simple SRF-based formula for predicting NBGFR in kidney donors.
• To assess the accuracy and reliability of the SRF formula in a cohort of living kidney donors.

Main Methods:

• Eighty-three patients undergoing DN from 2010-2016 were analyzed.
• Pre-operative CT imaging determined SRF (contralateral kidney volume/total kidney volume).
• The formula: Predicted NBGFR = 1.24 × (Pre-DN Global GFR) × (SRF) was applied.

Main Results:

• The SRF-based formula showed strong correlation with observed NBGFR (Pearson's r = 0.729).
• The prediction demonstrated minimal bias (median difference = 7.190 mL/min/1.73m²).
• High accuracy was observed: 96.4% within ±30% and 62.7% within ±15% of observed NBGFR.

Conclusions:

• The SRF-based formula accurately predicts NBGFR in living kidney donors.
• The formula can effectively discriminate patients with NBGFR > 45 mL/min/1.73m².
• Optimized pre-operative counseling for donor post-operative renal outcomes is facilitated by this predictive tool.