What the study found
The urinary calcium-to-citrate (Ca/Cit) ratio, a measure of calcium relative to citrate in urine, showed moderate ability to distinguish stone-forming from non-stone-forming children under 24 months old. A higher ratio was seen in hypercalciuric stone-formers than in the other groups.
Why the authors say this matters
The authors conclude that the Ca/Cit ratio may serve as a practical adjunctive marker of stone risk in infants and toddlers evaluated for suspected urinary stone disease. They also say the findings provide an age-appropriate reference distribution for children without stones and normal urinary calcium excretion.
What the researchers tested
The researchers did a retrospective single-center study of 181 children aged 1-24 months who had metabolic testing and ultrasonography at first visit to a tertiary pediatric nephrology clinic between 2012 and 2024. They grouped children as normocalciuric stone-free controls, hypercalciuric stone-formers, or non-hypercalciuric stone-formers, and used receiver operating characteristic (ROC) analysis to assess how well the spot urine Ca/Cit ratio predicted stones.
What worked and what didn't
The Ca/Cit ratio differed significantly across groups, with the highest values in hypercalciuric stone-formers (0.46 mg/mg) compared with controls (0.17 mg/mg) and non-hypercalciuric stone-formers (0.31 mg/mg). A threshold above 0.23 mg/mg had moderate diagnostic performance, with an area under the curve of 0.695, sensitivity of 66.1%, and specificity of 63.2%.
What to keep in mind
This was a retrospective study from a single center, so the findings may not generalize broadly. The abstract says larger prospective studies are needed to validate reference intervals and refine cut-off values for this age group.
Key points
- The urinary calcium-to-citrate ratio was higher in stone-forming children than in stone-free controls.
- Hypercalciuric stone-formers had the highest Ca/Cit ratio among the groups studied.
- A Ca/Cit cutoff above 0.23 mg/mg showed moderate ability to detect stones.
- Age did not show a meaningful correlation with Ca/Cit values in this study.
- The authors call for larger prospective studies to confirm reference ranges and cut-off values.
Disclosure
- Research title:
- Urinary calcium-to-citrate ratio helps identify stone risk in infants
- Authors:
- Utku Dönger, Meraj Alam Siddiqui, Aysun Çaltık Yılmaz, Caner İncekaş, Esra Baskın
- Institutions:
- Başkent University, Başkent University, Başkent University, Başkent University
- Publication date:
- 2026-02-11
- OpenAlex record:
- View
Get the weekly research newsletter
Stay current with scholarly research without reading academic papers — one filtered digest, every Friday.