Oxalate and Citrate in Humans - Response to Citrate

NCT06944223 | Recruiting

• 2 other identifiers: IRB25-00305K23DK127252-03
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

This is a single-center study that aims to learn more about how two compounds found in food, oxalate and citrate, interact in the body and may influence a person's chances of forming kidney stones. The study will examine changes in urinary oxalate and citrate levels after participants consume potassium citrate.

Conditions

Kidney Stone; Healthy

Keywords

kidney stone; kidney stones

Outcome Measures

Primary Outcomes (3)

• Change in urine oxalate from baseline to 2-hours, 4-hours, and 6-hours after potassium citrate consumption.

  Urine oxalate will be measured or calculated at time points 0, 2-hours, 4-hours, and 6-hours after sodium oxalate consumption. We will compare change in urine citrate and fractional excretion of citrate by change in oxalate at each time period for all participants.

  6 hours

• Change in urine citrate from baseline to 2-hours, 4-hours, and 6-hours after potassium citrate consumption.

  Urine citrate will be measured or calculated at time points 0, 2-hours, 4-hours, and 6-hours after sodium oxalate consumption. We will compare change in urine citrate and fractional excretion of citrate by change in oxalate at each time period for all participants.

  6 hours

• Change in fractional excretions of citrate and oxalate from baseline to 2-hours, 4-hours, and 6-hours after potassium citrate consumption.

  Fractional excretion of citrate will be measured or calculated at time points 0, 2-hours, 4-hours, and 6-hours after sodium oxalate consumption. We will compare change in urine citrate and fractional excretion of citrate by change in oxalate at each time period for all participants.

  6 hours

Secondary Outcomes (3)

• Difference in change in urine oxalate from baseline between kidney stone patients and controls.

  6 hours

• Difference in change in urine citrate from baseline between kidney stone patients and controls.

  6 hours

• Difference in change in fractional excretions of citrate and oxalate from baseline between kidney stone patients and controls.

  6 hours

Study Arms (2)

Kidney stone formers

OTHER

12 stone-forming subjects will be enrolled in this arm.

Other: Kidney stone formers

Control cohort

OTHER

12 non-stone-forming subjects will be enrolled in this arm.

Other: Control cohort

Interventions

Kidney stone formers OTHER

Consuming a special drink (potassium citrate) during an all-day visit to the University of Chicago research clinic Subjects in both groups will be asked to partake in the same activities, as follows: The day before presenting to the research clinic, subjects will collect urine at home. Subjects will then come to the research clinic at the University of Chicago in Hyde Park, where they will spend most of the day. We will give them a special liquid that contains potassium citrate. After this, we will collect urine and blood samples throughout the day. While at the clinic, subjects will also receive a boxed lunch at the end of the visit.

Kidney stone formers

Control cohort OTHER

Consuming a special drink (potassium citrate) during an all-day visit to the University of Chicago research clinic Subjects in both groups will be asked to partake in the same activities, as follows: The day before presenting to the research clinic, subjects will collect urine at home. Subjects will then come to the research clinic at the University of Chicago in Hyde Park, where they will spend most of the day. We will give them a special liquid that contains potassium citrate. After this, we will collect urine and blood samples throughout the day. While at the clinic, subjects will also receive a boxed lunch at the end of the visit.

Control cohort

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Stone formers (SF):
• Age 18-70
• History of at least one calcium-based kidney stone
• Non-stone formers (NSF):
• Age 18-70
• No history of kidney stone
• hour urine oxalate within laboratory normal range (\<50 mg/day)

You may not qualify if:

• History of primarily uric acid, cysteine, or struvite stones
• History of severe acid-base abnormality, very low (less than 100 mg/day) or very high (greater than 1500 mg/day) urine citrate
• Any controls or stone former (SF) participants who cannot stop diuretic medication or alkali supplementation for the course of the study period
• Chronic kidney disease (glomerular filtration rate \<75 milliliters per minute per 1.73 square meters \[mL/min/1.73 m²\])
• Non-stone formers (NSF) and stone formers (SF) with extreme levels of urine citrate will be excluded from this small initial study to reduce heterogeneity and remove focus from the extremes of citrate levels.

Sponsors & Collaborators

• University of Chicago: lead
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

University of Chicago Medical Center

Chicago, Illinois, 60637, United States

RECRUITING

MeSH Terms

Conditions

Kidney Calculi

Condition Hierarchy (Ancestors)

Nephrolithiasis; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Urolithiasis; Urinary Calculi; Male Urogenital Diseases; Calculi; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 17, 2025
• First Posted: April 25, 2025
• Study Start: October 1, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): June 1, 2027
• Last Updated: December 16, 2025

Record last verified: 2025-12

Locations

US (1)