Post-kidney donation glomerular filtration rate measurement and estimation

Area of Science:

• Nephrology
• Transplant Surgery
• Clinical Chemistry

Background:

• Assessing long-term consequences of kidney donation is crucial for donor safety.
• Glomerular filtration rate (GFR) is a key indicator of renal and cardiovascular risk.
• Limited data exists in Latin America on kidney function evaluation in donors using GFR measurement techniques.

Purpose of the Study:

• To evaluate the performance of the MDRD and CKD-EPI equations in assessing post-nephrectomy GFR dynamics in kidney donors.
• To compare estimated GFR (eGFR) with measured GFR (mGFR) in kidney donors.
• To determine the accuracy of GFR estimation equations in long-term donor follow-up.

Main Methods:

• Prospective cohort study of 189 kidney donors undergoing nephrectomy (2007-2016).
• GFR was measured using iothalamate clearance (HPLC) and estimated using MDRD and CKD-EPI equations pre- and post-nephrectomy.
• Donors were divided into two groups based on follow-up duration: up to 5 years (Group 1) and 5-10 years (Group 2).

Main Results:

• Both MDRD and CKD-EPI equations underestimated GFR compared to measured GFR (mGFR).
• CKD-EPI demonstrated better diagnostic performance (Area Under Curve: 0.79) than MDRD (AUC: 0.66) for identifying GFR < 60 ml/min/1.73m².
• Estimated GFR showed poor performance in donors over 50 years of age in long-term follow-up.

Conclusions:

• GFR estimation equations exhibit suboptimal performance for long-term monitoring of post-nephrectomy GFR in kidney donors.
• Direct measurement of GFR is recommended for screening and follow-up of select kidney donors.
• Accurate GFR assessment is vital for ensuring the long-term health and safety of kidney donors.