Urolithiasis, Calcium Oxalate

The goal of this clinical trial study is to test if patients with idiopathic calcium oxalate kidney stones have an increased production of oxalate by the body, which would lead to increased urinary excretion of oxalate. The study will recruit adult patients with a history of calcium oxalate kidney stones and healthy volunteers without kidney stones. Participants will ingest fixed diets containing low amounts of oxalate for 5 days ingest a soluble form of glycolate and vitamin C collect urine, blood, stool during the dietary and oral dosing portions of the study and also collect breath sample during the oral glycolate test

The goal of this clinical trial study is to test if patients with idiopathic calcium oxalate kidney stones have an increased absorption of dietary oxalate, which would lead to increased urinary excretion of oxalate. The study will recruit adult patients with a history of calcium oxalate kidney stones and healthy volunteers without kidney stones. Participants will * ingest fixed diets containing low and moderately high amounts of oxalate for 5 days at a time * ingest a soluble form of oxalate and sugar preparations to test gut permeability * collect urine, blood, stool and breath sample during the fixed diets and the soluble oxalate test

The goal of this trial is to test if colonization with the gut bacteria Oxalobacter formigenes leads to a reduction in urinary oxalate excretion in patients with calcium oxalate kidney stone disease. The study will recruit adult participants with a history of calcium oxalate kidney stones who are not colonized with Oxalobacter formigenes. Participants will * ingest fixed diets containing low and moderately high amounts of oxalate for 4 days at a time * collect urine, blood and stool samples during the fixed diets * ingest a preparation of live Oxalobacter formigenes to induce colonization with Oxalobacter formigenes

Goal of this trial: To test a new tool called VISOR in adults (aged 18-80) with 1-3 cm kidney or ureter stones. We want to see: 1. If it's safe and works well 2. If its built-in features (flushing/suction, pressure control, and stone-breaking/removal) help clear stones better while keeping surgery safe. Main questions: 1. Can the VISOR clear stones successfully (with fragments \<4 mm left) for at least 9 out of every 10 people within 24 hours after surgery? 2. Will serious problems (like severe infections or ureteral injuries) happen to no more than 1 in 20 people (5%)? 3. Can the device keep pressure inside the kidney below 30 mmHg (a safe level) during the entire surgery? What participants will do: Have stone removal surgery using VISOR (breaks and removes stones at the same time). Get a CT scan within 24 hours after surgery to check if stones are cleared. Return 4 weeks (±1 week) after surgery for: An imaging test (CT or ultrasound) A check for any health problems related to the surgery.

This prospective randomized controlled clinical study aims to evaluate the safety and efficacy of a novel Vortex Intelligence Stone Optimized Removal (VISOR,The experimental group) system compared to a single-use ureterorenoscope (the control) for treating upper urinary tract stones. A total of 100 patients with upper urinary tract stones (cumulative stone diameter ≤3 cm) will be enrolled and randomly assigned in a 1:1 ratio to either the experimental group (n=50) or the control group (n=50). The experimental group will undergo surgery using the innovative system, which integrates irrigation-suction, pressure monitoring-regulation, and lithotripsy-evacuation functions. The control group will be treated with a conventional single-use ureterorenoscope. The primary outcome measure is the immediate stone-free rate (SFR), defined as the proportion of patients with residual fragments \<4 mm on renal non-contrast computed tomography (NCCT) performed within 24 hours postoperatively. Key secondary endpoints include the SFR at 3 months, operative and lithotripsy times, total laser energy used, intraoperative ureteral injury (Traxer grading), postoperative pain scores, incidence of fever (\>38.0°C), and overall complication rates (Clavien-Dindo classification). Patient follow-up assessments will be conducted at 24 hours, 21±7 days, and 90±14 days post-surgery to monitor stone clearance, complications, and recovery. This study seeks to determine if the novel system offers superior stone clearance while maintaining a safe renal pelvic pressure profile, potentially improving outcomes for patients with larger renal stones treated ureteroscopically.