Kidney Stones
Conditions
Keywords
kidney stones, calcium oxalate, nephrolithiasis
Brief summary
This single-center randomized controlled trial at Mount Sinai West will enroll 80 patients undergoing percutaneous nephrolithotomy for calcium oxalate stones. Participants will be randomized to receive either empiric therapy or selective therapy guided by 24-hour urine evaluation. The primary outcome is change in calcium oxalate supersaturation at 4 weeks, aiming to determine whether empiric therapy can provide outcomes comparable to selective therapy while simplifying access to prevention.
Detailed description
This is a single-center, randomized controlled trial evaluating the effectiveness of empiric versus selective medical therapy for the prevention of calcium oxalate kidney stones. The study will enroll 80 patients at Mount Sinai West undergoing percutaneous nephrolithotomy (PCNL) for predominantly calcium oxalate stones. Participants will be randomized postoperatively to receive either empiric therapy (based on stone composition and urinalysis) or selective therapy (based on 24-hour urine metabolic evaluation). The primary endpoint is the change in calcium oxalate supersaturation (ssCaOx) at 4 weeks post-treatment. The study is designed to determine whether an empiric approach can achieve comparable outcomes to selective therapy while simplifying access to preventive treatment.
Interventions
DRUGChlorthalidone
Chlorthalidone 25 mg orally once daily is used to reduce urinary calcium excretion and prevent recurrent calcium-containing kidney stones. In this study, it is prescribed either based on stone composition (empiric group) or guided by 24-hour urine results (selective group) for participants meeting criteria for hypercalciuria or calcium oxalate dihydrate stones.
BEHAVIORALLow oxalate diet
Participants receive counseling to follow a low oxalate diet, limiting high oxalate foods (\>50 mg/100 g) and restricting moderate oxalate foods (\<50 mg/100 g) to a single four-ounce serving per day. The diet is prescribed either based on stone composition (empiric group) or guided by 24-hour urine results (selective group) for participants with idiopathic hyperoxaluria or calcium oxalate monohydrate stones.
Sponsors
Icahn School of Medicine at Mount Sinai
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult age of 18 years * Diagnosed with kidney stones and scheduled for PCNL. * Calcium Oxalate Stone Former * Pre-operative CT-scan within 90 days of surgery and stone density with \> 1000 Hounsfield units * Non-pregnant or breastfeeding * Able and willing to provide informed consent. * Pre-operative eGFR greater than 70 mL/min/1.73 m² -Negative pre-operative urine culture
Exclusion criteria
* Documented history of gastric or intestinal bypass, liver disease, history of gastrointestinal malabsorptive disease (Crohn's disease, ulcerative colitis, and short-gut syndrome) * Hyperparathyroidism -Renal tubular acidosis * Active kidney stone prevention treatment (use of thiazides, alkaline therapy, or low oxalate diet) at the time of surgery * History of hypokalemia or baseline hypotension * Allergy to medications used in trial or sulfa-containing medications * Patient prescribed thiazide, loop diuretics, carbonic anhydrase inhibitors, xanthine oxidase inhibitors, active Vitamin D, bisphosphonates, denosumab, glucocorticoids, or potassium supplementation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in super saturation of calcium oxalate | 4-6 weeks | Change in urine calcium oxalate supersaturation from baseline to the final follow-up visit, measured via 24-hour urine collection. This is a marker that can be predictive of stone episodes, as recurrent stones may take years to develop. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in urinary oxalate levels | 4-6 weeks | Difference in 24-hour urinary oxalate excretion from baseline to the final follow-up visit, measured in mg/day, to assess the effect of dietary and pharmacologic interventions on oxalate levels. |
| Changes in urinary calcium levels | 4-6 weeks | Difference in 24-hour urinary calcium excretion from baseline to the final follow-up visit, measured in mg/day, to evaluate the effect of chlorthalidone and dietary interventions on urinary calcium levels. |
| Chlorthalidone Adherence Survey (adapted from Brief Medication Questionnaire) | 4-6 weeks | Participant-reported adherence to prescribed chlorthalidone therapy, assessed via a structured survey at the follow-up visit, to evaluate compliance with the study intervention. Response will be either 0=nonadherent or 1=adherent. |
Countries
United States
Contacts
CONTACTBlair Gallante, MPH
CONTACTMantu Gupta, MD
PRINCIPAL_INVESTIGATORMantu Gupta, MD
Mount Sinai West
Outcome results
None listed