Abstract
Background
The renal cortex volume is associated with the kidney function and chronic kidney disease (CKD) risk factors, and it may also be a prognostic factor. We aimed to create an equation to estimate the renal cortex volume of CKD patients in day-to-day clinical practice.
Methods
The subjects included 116 ethnic Japanese CKD patients who were ≥ 18 years of age. The renal size (length, width and thickness) was measured by ultrasound. The body height, weight, year of age, sex, birth weight, gestational age, diabetes status, hypertension status, family history of CKD and dialysis and estimated glomerular filtration rate (eGFR) were collected as expected dependent variables. We made models for the equation regarding the renal cortex volume measured by non-contrast magnetic resonance imaging as a true renal cortex volume. Stepwise multiple linear regression analyses were performed with the log-transformation of dependent and independent variables. The accuracy of the models was compared using the leave one out cross-validation method.
Results
The estimated volume of the renal cortex (cm3) = 0.012 × renal length (cm)0.92 × width (cm)0.53 × body weight (kg)0.40 × body height (cm)0.67 × eGFR (ml/min/1.73 m2)0.22 × 1.12 if diabetes. The adjusted R 2 value and the accuracy within 30 and 50% were 0.73, 0.94 and 0.99, respectively.
Conclusions
This study provided a new method for estimating the renal cortex volume in day-to-day clinical practice.
Similar content being viewed by others
References
Wang X, Vrtiska TJ, Avula RT, Walters LR, Chakkera HA, Kremers WK, et al. Age, kidney function, and risk factors associate differently with cortical and medullary volumes of the kidney. Kidney Int. 2014;85:677–85.
Woodard T, Sigurdsson S, Gotal JD, Torjesen AA, Inker LA, Aspelund T, et al. Segmental kidney volumes measured by dynamic contrast-enhanced magnetic resonance imaging and their association with CKD in older people. Am J Kidney Dis. 2015;65:41–8.
O’Neill WC. Structure, not just function. Kidney Int. 2014;85:503–5.
Halleck F, Diederichs G, Koehlitz T, Slowinski T, Engelken F, Liefeldt L, et al. Volume matters: CT-based renal cortex volume measurement in the evaluation of living kidney donors. Transpl Int. 2013;26:1208–16.
Raman GV, Clark A, Campbell S, Watkins L, Osmond C. Is blood pressure related to kidney size and shape? Nephrol Dial Transplant. 1998;13:728–30.
Emamian SA, Nielsen MB, Pedersen JF, Ytte L. Kidney dimensions at sonography: correlation with age, sex, and habitus in 665 adult volunteers. AJR Am J Roentgenol. 1993;160:83–6.
Herrmann J, Wenzel U, Galler S, Schoennagel BP, Busch JD, Tozakidou M, et al. Diffusion-weighted imaging of the kidneys in haemolytic uraemic syndrome. Eur Radiol. 2017;. doi:10.1007/s00330-017-4848-2.
Imasawa T, Nakazato T, Ikehira H, Fujikawa H, Nakajima R, Ito T, et al. Predicting the outcome of chronic kidney disease by the estimated nephron number: the rationale and design of PRONEP, a prospective, multicenter, observational cohort study. BMC Nephrol. 2012;13:11.
Nakazato T, Ikehira H, Imasawa T. Determinants of renal shape in chronic kidney disease patients. Clin Exp Nephrol. 2016;20:748–56.
Hallan S, Euser AM, Irgens LM, Finken MJ, Holmen J, Dekker FW. Effect of intrauterine growth restriction on kidney function at young adult age: the Nord Trondelag Health (HUNT 2) Study. Am J Kidney Dis. 2008;51:10–20.
Aly H, Davies J, El-Dib M, Massaro A. Renal function is impaired in small for gestational age premature infants. J Matern Fetal Neonatal Med. 2013;26:388–91.
Matsuo S, Imai E, Horio M, Yasuda Y, Tomita K, Nitta K, et al. Revised equations for estimated GFR from serum creatinine in Japan. Am J Kidney Dis. 2009;53:982–92.
DuBois D, DuBois EF. A formula to estimate the approximate surface area if height and weight be known. Arch Intern Med. 1916;1916(17):863–71.
Fujimoto S. Watanabe T [Studies on surface area of Japanese. 16. New calculation formula (1) for general use]. Nihon Eiseigaku Zasshi. 1967;21:403–6.
Karstoft K, Lodrup AB, Dissing TH, Sorensen TS, Nyengaard JR, Pedersen M. Different strategies for MRI measurements of renal cortical volume. J Magn Reson Imaging. 2007;26:1564–71.
Zollner FG, Svarstad E, Munthe-Kaas AZ, Schad LR, Lundervold A, Rorvik J. Assessment of kidney volumes from MRI: acquisition and segmentation techniques. AJR Am J Roentgenol. 2012;199:1060–9.
Torimoto I, Takebayashi S, Sekikawa Z, Teranishi J, Uchida K, Inoue T. Renal perfusional cortex volume for arterial input function measured by semiautomatic segmentation technique using MDCT angiographic data with 0.5-mm collimation. AJR Am J Roentgenol. 2015;204:98–104.
Stevens CF. Darwin and Huxley revisited: the origin of allometry. J Biol. 2009;8:14.
Statistics calculators: a priori sample size calculator for multiple regression; http://www.danielsoper.com/statcalc3/calc.aspx?id=1. Accessed 1 June 2012.
Mounier-Vehier C, Lions C, Devos P, Jaboureck O, Willoteaux S, Carre A, et al. Cortical thickness: an early morphological marker of atherosclerotic renal disease. Kidney Int. 2002;61:591–8.
Hermanussen M, Danker-Hopfe H, Weber GW. Body weight and the shape of the natural distribution of weight, in very large samples of German, Austrian and Norwegian conscripts. Int J Obes Relat Metab Disord. 2001;25:1550–3.
Emamian SA, Nielsen MB, Pedersen JF. Intraobserver and interobserver variations in sonographic measurements of kidney size in adult volunteers. A comparison of linear measurements and volumetric estimates. Acta Radiol. 1995;36:399–401.
Thakur V, Watkins T, McCarthy K, Beidl T, Underwood N, Barnes K, et al. Is kidney length a good predictor of kidney volume? Am J Med Sci. 1997;313:85–9.
Geelhoed JJ, Kleyburg-Linkers VE, Snijders SP, Lequin M, Nauta J, Steegers EA, et al. Reliability of renal ultrasound measurements in children. Pediatric nephrology. 2009;24:1345–53.
Acknowledgements
We thank Ryo Nakajima for providing technical support, Keiko Tanaka and Mori Tachibana for their assistance in the data management and Hiroyuki Fujikawa for performing MRI examination.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Ethical approval
The study was performed in accordance with the Declaration of Helsinki and was approved by the institutional review board of the Committee on Ethics in Human Research of National Hospital Organization Chiba-East National Hospital in December 2010 (No. 19).
Informed consent
Written informed consent was obtained from each patient.
Conflict of interest
The authors have declared that no conflict of interest exists.
Funding
This work was supported by a Grant for NHO network clinical research Grant no. H26-NHO (Tounyo)-01 from the National Hospital Organization of Japan to Toshiyuki Imasawa.
About this article
Cite this article
Nakazato, T., Ikehira, H. & Imasawa, T. An equation to estimate the renal cortex volume in chronic kidney disease patients. Clin Exp Nephrol 22, 603–612 (2018). https://doi.org/10.1007/s10157-017-1492-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10157-017-1492-8