Study of How Oxalate Absorption Affects Kidney Stone Risk in Obese and Roux-en-Y Gastric Bypass Patients

What this Trial Is About

This research aims to better understand how oxalate, a compound found in many foods, affects the risk of forming kidney stones. It focuses on three groups of people who have formed kidney stones those who have had Roux-en-Y gastric bypass surgery, obese individuals, and non-obese individuals. The study seeks to learn how much oxalate is absorbed through the digestive system and how this varies among these groups, which may help guide better treatments for kidney stone risk. Participants will follow a very low oxalate diet 50 mg per day for five days. For the first two days, they will eat a special diet at home. From days 3 to 5, special meals will be delivered to their homes from a research clinic. On days 4 and 5, they will collect 24-hour urine samples. On day 6, participants will visit the research clinic for most of the day to receive a special oxalate-containing liquid and a specially prepared breakfast low in oxalate and citrate. Blood and urine samples will be collected throughout the day. During the study, participants will have their urine oxalate and citrate levels measured before and after the low oxalate diet. The research team will monitor absorption of labeled oxalate and sucralose through urine and blood tests. These measurements will help determine how much oxalate is absorbed from the digestive tract and its role in kidney stone formation. The study lasts about one week, with close monitoring to understand oxalate absorption and kidney stone risk in different patient groups.

GI Oxalate Absorption