Calcium/Citrate Ratio and Risk of Kidney Stone

Reply to: Calcium/Citrate Ratio and Risk of Kidney Stone

Does the Urinary Calcium/Citrate Ratio Add to the Diagnostic Workup of Children at Risk of Kidney Stones? A Cross-Sectional Study

We read the publication on “Does the Urinary Calcium/Citrate (UCa/UCi) Ratio Add to the Diagnostic Workup of Children at Risk of Kidney Stones?” with a great interest. Lee et al noted in the article “UCa/UCi rather than UCi/UCr may be more predictive in the clinical setting when evaluating for nephrolithiasis.[1]” The result in this report is concordant with the previous publication by DeFoor et al.[2] Nevertheless, there is an important consideration regarding the urine calcium and citrate measurement. The sexual variation should also be mentioned. For urine calcium, there is no sexual variation; however, a sexual variation is reported for urine citrate.[3] This variation should be kept in mind while interpreting the UCa/UCi ratio in pediatric patients.

• References

• 1 Lee M, Cuellar CIR, Nagra R, Wang ZTP, VBhayana V, Filler G. Does the urinary calcium/citrate ratio add to the diagnostic workup of children at risk of kidney stones? A cross-sectional study. J Child Sci 2019; 9: 1-6
• 2 DeFoor W, Jackson E, Schulte M, Alam Z, Asplin J. Calcium-to-citrate ratio distinguishes solitary and recurrent urinary stone forming children. J Urol 2017; 198 (02) 416-421
• 3 Perry GM, Scheinman SJ, Asplin JR. Effects of sex on intra-individual variance in urinary solutes in stone-formers collected from a single clinical laboratory. PLoS One 2013; 8 (06) e53637