Investigating oxalate production in patients with calcium oxalate kidney stones

Endogenous Oxalate Synthesis in Idiopathic Calcium Oxalate Kidney Stone Formers

Not applicable Interventional University of Alabama at Birmingham · NCT06989320

This study is testing if people with calcium oxalate kidney stones produce more oxalate in their bodies than healthy individuals by following a special diet and taking certain supplements.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment80 (estimated)
Ages18 Years to 80 Years
SexAll
SponsorUniversity of Alabama at Birmingham Academic / other
Locations2 sites (Birmingham, Alabama and 1 other locations)
Trial IDNCT06989320 on ClinicalTrials.gov

What this trial studies

This clinical trial aims to determine if individuals with idiopathic calcium oxalate kidney stones produce more oxalate in their bodies compared to healthy individuals. Participants will follow a low-oxalate diet for five days and undergo tests involving the ingestion of glycolate and vitamin C to measure oxalate production. The study will recruit 80 subjects, including 40 kidney stone formers and 40 healthy controls, matched by age and gender. Urine, blood, and stool samples will be collected to analyze the effects of diet and oral dosing on oxalate synthesis.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18-80 with a history of calcium oxalate kidney stones.

Not a fit: Patients with chronic kidney disease, primary hyperoxaluria, or other significant renal or metabolic disorders may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to better understanding and management of calcium oxalate kidney stones, potentially reducing recurrence rates.

How similar studies have performed: While this approach is novel in its specific focus on endogenous oxalate synthesis, similar studies have explored dietary impacts on kidney stone formation with varying degrees of success.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* age 18-80 yrs
* Body Mass Index \> 18.5 kg/m2
* Normal fasting serum electrolytes on comprehensive metabolic profile
* Willing to ingest fixed diets
* Willing to stop supplements (vitamins including vitamin C, calcium (citrate or carbonate) and other minerals, herbal supplements, nutritional aids, probiotics) for 2 weeks before start and during study.
* For stone formers: first time or recurrent Calcium Oxalate stone former. Composition of most recent stone ≥ 50% calcium oxalate if available, uric acid component \<20%

Exclusion Criteria:

* Chronic Kidney Disease stage 4-5
* Primary hyperoxaluria, Enteric (secondary) hyperoxaluria
* Liver, bowel, endocrine or renal diseases (other than idiopathic Calcium Oxalate kidney stones) or any other condition that may influence the absorption, transport or urinary excretion of ions, which will compromise the interpretation of results, including: Cystic fibrosis, Celiac disease, Cystinuria, Uric acid stone former, Nephrotic syndrome, Sarcoidosis, Renal tubular acidosis, Primary hyperparathyroidism, Neurogenic bladder, Urinary diversion, Chronic diarrhea, Bariatric surgery, Inflammatory bowel disease
* Pregnancy or breast-feeding
* Incompatible dietary requirements with the study, food allergies or intolerance to any of the foods in study menus
* Active malignancy or treatment for malignancy within 12 months prior to screening
* Utilization of immunosuppressive medication
* Uncontrolled hypertension or diabetes
* Diabetes type 1

Where this trial is running

Birmingham, Alabama and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Kidney StonesKidney CalculiUrolithiasisUrolithiasis, Calcium OxalateNephrolithiasisNephrolithiasis, Calcium OxalateOxalate UrolithiasisHealthy
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.