Endogenous Oxalate Synthesis in Idiopathic Calcium Oxalate Kidney Stone Disease

Launched by UNIVERSITY OF ALABAMA AT BIRMINGHAM · May 16, 2025

Keywords

ClinConnect Summary

This clinical trial is designed to understand whether people who form calcium oxalate kidney stones produce more oxalate in their bodies compared to those who don’t have kidney stones. The study will include adults aged 18 to 80, specifically targeting those who have a history of calcium oxalate stones, as well as healthy volunteers without any history of kidney stones. Participants will follow a special low-oxalate diet for five days, take a soluble form of glycolate and vitamin C, and provide samples of their urine, blood, stool, and breath throughout the study.

To be eligible, participants must be healthy adults with a body mass index (BMI) over 18.5 and normal blood tests. They should also be willing to stop taking certain supplements for two weeks before and during the study. However, those with certain health conditions, such as advanced kidney disease, liver or bowel diseases, or anyone currently pregnant or breastfeeding, will not be eligible to participate. If you decide to join this study, you will help researchers learn more about kidney stones and how the body processes oxalate, which could lead to better prevention strategies for stone formation in the future.

Gender

ALL

Eligibility 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