Relationship among total kidney volume, renal function and age.

PURPOSE

We measured kidney volume using software and investigated the relationship between kidney volume and renal function.

MATERIALS AND METHODS

Age, gender, height, body weight, body mass index, body surface area and serum creatinine were recorded for 539 normal individuals. A tissue segmentation tool program was used to measure kidney volume from computerized tomography images. The glomerular filtration rate was calculated using the Cockcroft-Gault equation and an abbreviated modification of diet in renal disease equation. We looked for correlations of renal parenchymal volume with age and anthropometric measurements. We also tested for a correlation between kidney volume and renal function using the glomerular filtration rate according to the Cockcroft-Gault and modification of diet in renal disease equations.

RESULTS

Mean kidney volume in all participants was 261.3 ± 58.1 ml. Mean volume in men was approximately 14 ml greater than in women (266.1 vs 251.8 ml, p = 0.004). Kidney volume correlated significantly with height (r = 0.344, p <0.001), body weight (r = 0.343, p <0.001), body mass index (r = 0.177, p <0.001), body surface area (r = 0.371, p <0.001) and age (r = -0.418, p <0.001). Kidney volume also correlated with the glomerular filtration rate according to the Cockcroft-Gault and modification of diet in renal disease equations (p <0.001, r = 0.615 and p <0.001, r = 0.432, respectively). Kidney volume and the glomerular filtration rate decreased in parallel with increasing age.

CONCLUSIONS

Kidney volume correlates well with renal function and anthropometric measurements. Knowledge of these relationships will be valuable in clinical urology and nephrology.