Correlation of the Renal Cortex Volume With the Glomerular Filtration Rate in Live Donors for Renal Transplantation

As a pretransplantation evaluation, renal function is determined by the glomerular filtration rate (GFR) with the use of renal scintigraphy (RS) and the estimated glomerular filtration rate (eGFR). To date, there are few studies that correlate renal cortex volume with eGFR determined with renal gammagram (GR) and eGFR by equations (Cockroft-Gault, Modification of Diet in Renal Disease, and Chronic Kidney Disease Epidemiology Collaboration equation) in Latin American living donors.

This study sought to determine whether there is correlation of the volume of the renal cortex by Herts equation with the GFR determined with renal gammagram (GFR-GR).

This was an analytical, observational, and cross-sectional study. A review of the donor charts from January 1, 2014, to December 1, 2014, with a complete clinical file, kidney measurements, predonation tomography volume, and eGFR by different formulas and by renal scintigraphy.

Thirty-three donors were included, 51.5% male and 48.5% female. The mean age was 38.58 ± 10 years, with an average volume of 127.83 ± 28.30 mL, with diethylenetriamine-pentaacetate (DTPA) of 54.80 ± 7.13 mL/min/1.73 m² in the donated kidney. Spearman correlation showed the best association with the Herts equation (r = 0.346) reaching significance (P = .049) when comparing the different equations against the GFR with DTPA. Using the Bland-Altman method, the lowest variability and best significance was verified with the same equation compared to the other formulas (P = .0002).

There is no consensus regarding which is the best formula for calculating the GFR of both kidneys. Of the different formulas, the one that best correlated with the GFR was the Herts method, which uses the volume of the kidney.