Gut Oxalate Absorption in Calcium Oxalate Stone Disease

Launched by UNIVERSITY OF ALABAMA AT BIRMINGHAM · Mar 25, 2024

Keywords

ClinConnect Summary

This clinical trial is studying how well patients with calcium oxalate kidney stones absorb oxalate from their diet. The researchers want to find out if these patients absorb more dietary oxalate, which could lead to higher levels of oxalate in their urine. To do this, they will recruit adults aged 18 to 70 who either have a history of calcium oxalate kidney stones or are healthy volunteers without stones.

Participants in the trial will follow specific diets for five days, consuming either low or moderate amounts of oxalate. They will also take a special form of oxalate and sugar to help test how well their gut absorbs these substances. Throughout the study, participants will need to collect urine, blood, stool, and breath samples for analysis. To be eligible, participants must be willing to stop certain vitamins and supplements for two weeks before and during the study. It’s important to note that individuals with certain health conditions, such as chronic kidney disease or pregnancy, will not be able to participate. This study aims to improve our understanding of kidney stone formation and could help develop better prevention strategies for those at risk.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • age 18-70 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
• • Chronic NSAID use