Urinary Sodium to Potassium Ratio in Pediatric Stone Patients

Department of Pediatric Nephrology, University of Illinois College of Medicine at Peoria (UICOMP), Peoria, Il, USA

*Corresponding author: Vimal Master Sankar Raj, Department of Pediatric Nephrology, University of Illinois College of Medicine at Peoria (UICOMP), Peoria, Il, USA, E-mail: [email protected].
Received: November 26, 2020
Published: December 28, 2020

 ABSTRACT

The incidence of pediatric stone disease is on the rise. Dietary elements including high salt intake and reduced water consumption remain the major risk factors for stone formation. Urinary stone profile in pediatric literature remains limited. The purpose of the study is to a) compare the urinary sodium/potassium (Na/K) molar ratio in pediatric stone patients at CHOI to the national average dietary intake and b) correlate the risk factors of stone formation with dietary factors in pediatric stone formers.

Methods: This retrospective cohort study included all Pediatric stone patients who attended outpatient Nephrology clinic from 03/1/2014 to 10/1/2018. Children with known metabolic/genetic causes for stone disease, incomplete 24 hr urinary collection or on medications that affect mineral excretions were excluded from the study. Statistical analysis was done using SAS 9.4. Descriptive data of the study population was provided. Hypothesis testing was done using one sample T test and predictive analysis performed using linear correlation and multiple regression models.

Results: 150 patient charts were screened and 89 included in the study. Average age of the study population was 12.7 years with 58% females and 42% males. Mean Na/K molar ratio in pediatric stone patient was 3.7, statistically significantly higher than the national average of 2.5 using one sample T test (P < 0.001). Urinary calcium excretion showed a strong linear correlation with sodium excretion (r 0.545, P < 0.001). Multiple regression models using urinary calcium excretion as the dependent variable showed correlation with urinary sodium excretion (P 0.004), urinary volume (P < 0.0001) and urinary pH (P 0.001).

Conclusion: 24 hr urinary sodium potassium molar ratio is significantly higher in stone formers indicating higher salt and lower potassium consumption when compared to national average intake. Water intake, salt consumption and alteration of urinary pH remain the main dietary modality to alter calcium excretion and hence reduce stone formation.

KEYWORDS: Sodium; Potassium; Pediatric Stone; Salt Consumption