Studying Oxalate Production in Adults With and Without Calcium Oxalate Kidney Stones Using Low-Oxalate Diets and Oral Glycolate and Vitamin C Tests

What this Trial Is About

Researchers are studying idiopathic calcium oxalate kidney stone disease to understand if patients produce more oxalate within their bodies, leading to higher urinary oxalate levels. The study compares adults with a history of calcium oxalate kidney stones to healthy volunteers without stones. This research aims to evaluate oxalate production and the role of vitamin C and glycolate metabolism in these patients using controlled diets and oral dosing tests. Participants will follow a low-oxalate fixed diet under 60 mgday with normal calcium intake for 5 days. They will then take oral doses of 13C-glycolate and 13C-ascorbic acid on separate visits while continuing the diet. Urine, blood, stool, and breath samples will be collected during these dosing tests over several hours. The study includes screening, dietary equilibration, and oral dosing phases. During the study, participants will collect 24-hour urine samples at home and provide blood and breath samples in the research unit. Researchers will monitor urinary oxalate excretion, endogenous oxalate production, and the contribution of vitamin C breakdown to oxalate levels. The total participation involves multiple visits with dietary control, sample collections, and metabolic tests to assess oxalate synthesis and metabolism.

Endogenous Oxalate Synthesis in Idiopathic Calcium Oxalate Kidney Stone Disease