Kidney StoneNCT04051346
Dietary Oxalate and Innate Immunity in Kidney Stone Disease
A study testing Low Oxalate Diet and High Oxalate Diet in people with Kidney Stone, run by University of Alabama at Birmingham at 1 site in United States.
Trial summary
This study will test whether oxalate stimulates urinary crystals and impacts the immune system in healthy subjects using two controlled diets (low and high oxalate). Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Kidney Stone
- What is being tested?
- Low Oxalate Diet and High Oxalate Diet
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 14 participants
- Where
- 1 siteUnited States
- Study dates
- 5 Mar 2021to 1 May 2025
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy subjects (men and women) between the ages of 18 and 60 years of age
- No calcium oxalate kidney stones or other medical conditions
- Normal comprehensive metabolic panel (CMP)
- Non tobacco users
- Not pregnant
- BMI between 20-30 kg/m2
- Willing to abstain from vigorous exercise and vitamins/supplements during the study
- Willing to consume only provided diets, accurately collect 24-hour urine samples, and have blood drawn
Who cannot join
- Inability to sign and read the informed consent
- Any medical, psychiatric, or social conditions that would prohibit participants from abiding by the study requirements
- Physician refusal
- Pregnant women
- Active medical problems
- History of kidney stones or any medical condition that could influence absorption or excretion of oxalate
Show all 9Show fewer
- Tobacco users
- Taking medications or dietary supplements
- BMI >30 or <20
Trial locations and contacts
1 site in 1 country.
United States1 site
University of Alabama at Birmingham
Birmingham, Alabama, 35233
About this study
This study will test whether oxalate stimulates urinary crystals and impacts the immune system in healthy subjects using two controlled diets (low and high oxalate).
Read the detailed description
Oxalate is a small molecule found in plants and plant-derived food. It has been shown that meals containing high amounts of oxalate can increase urinary oxalate excretion, which is a risk factor for calcium oxalate kidney stones (CaOx KS). Small increases in oxalate can stimulate urinary crystals to form which can elicit an immune response. This study consists of having healthy subjects consume both low and oxalate enriched diets to evaluate the effect of oxalate on urinary crystals and immune responses. Participants will receive a low or high oxalate diet for 4 days prior to having a wash out period for 6 days. Participants will then crossover to the opposite oxalate diet for four more days.
- Conditions
- Kidney Stone
- Being tested
- Low Oxalate Diet, High Oxalate Diet
- Keywords
- dietary oxalate, diet therapy
- Medical subject headings
- Kidney Calculi
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Low Oxalate DietDietary supplement
Participants will consume a diet that is controlled in its daily contents of oxalate and calcium, and in its content of carbohydrate, fat, and protein. Participants will be asked not to take any dietary supplements, to exercise strenuously, or to consume food or drink that is not provided to them.
High Oxalate DietDietary supplement
Participants will consume a diet that is controlled in its daily contents of oxalate and calcium, and in its content of carbohydrate, fat, and protein. Participants will be asked not to take any dietary supplements, to exercise strenuously, or to consume food or drink that is not provided to them.
| Study group | Role | What they receive |
|---|---|---|
| Low Oxalate Diet | Experimental | Subjects will consume a low oxalate diet for four days, with blood and 24-hour urine collections occurring at baseline and post diet. A ten day wash out period will follow, during which the subject will consume a self-selected diet. Subjects will then consume the high oxalate diet for the final four days, with blood and 24-hour urine collections once again occurring at baseline and post diet. Receives: Dietary Supplement: Low Oxalate Diet |
| High Oxalate Diet | Experimental | Subjects will consume a high oxalate diet for four days, with blood and 24-hour urine collections occurring at baseline and post diet. A ten day wash out period will follow, during which the subject will consume a self-selected diet. Subjects will then consume the low oxalate diet for the final four days, with blood and 24-hour urine collections once again occurring at baseline and post diet. Receives: Dietary Supplement: High Oxalate Diet |
What is being measured
The primary outcome is the main question the study is designed to answer.
Urinary Oxalate Excretion
Twenty-four hour urinary oxalate will be reported as mg/day.
Measured: Days 4 and 14
Crystalluria
Crystalluria will be reported as particles/ml.
Measured: Day 4 and 14
Number of Participants With Monocyte Cellular Energetics
Cellular energetic oxygen consumption traces will be examined.
Measured: Days 4 and 14
Secondary outcomes (1)
Number of Participants With Monocyte Transcriptomics
Monocyte cellular transcriptomics will be determined using RNA sequencing (mRNA).
Measured: Days 4 and 14
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Aug 2019
- Study start5 Mar 2021
- Primary completion1 May 2025
- Study completion1 May 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Kidney StoneStudies of the same condition, open and under way.
- More trials run by University of Alabama at BirminghamThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 14 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Alabama at Birmingham
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Tanecia Mitchell, PhD, University of Alabama at Birmingham
- Investigators
- Tanecia Mitchell, PhD, Principal investigator, University of Alabama at Birmingham
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04051346
- Sponsor's protocol ID
- IRB-300003865
- Other IDs
- R03DK123542
- Status last verified
- Apr 2026
- First submitted
- 1 Aug 2019
- Last updated
- 26 Jun 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Data may be shared with other scientists. All participants information will be de-identified.
Study at a glance
From the registry record, last updated by the sponsor on 26 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Dietary Oxalate and Innate Immunity in Kidney Stone Disease
- ClinicalTrials.gov ID
- NCT04051346
- Acronym / sponsor ID
- IRB-300003865
- Conditions
- Kidney Stone
- Keywords
- dietary oxalate, diet therapy
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 14 participants (actual)
- Lead sponsor
- University of Alabama at BirminghamUniversity, hospital or other
- Collaborators
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
- Study start
- 5 Mar 2021 (actual)
- Primary completion
- 1 May 2025 (actual)
- Study completion
- 1 May 2025 (actual)
- First posted
- 9 Aug 2019 (actual)
- Results
- Posted 26 Jun 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will test whether oxalate stimulates urinary crystals and impacts the immune system in healthy subjects using two controlled diets (low and high oxalate).
Detailed description
Oxalate is a small molecule found in plants and plant-derived food. It has been shown that meals containing high amounts of oxalate can increase urinary oxalate excretion, which is a risk factor for calcium oxalate kidney stones (CaOx KS). Small increases in oxalate can stimulate urinary crystals to form which can elicit an immune response. This study consists of having healthy subjects consume both low and oxalate enriched diets to evaluate the effect of oxalate on urinary crystals and immune responses. Participants will receive a low or high oxalate diet for 4 days prior to having a wash out period for 6 days. Participants will then crossover to the opposite oxalate diet for four more days.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Low Oxalate Diet | Experimental | Dietary Supplement: Low Oxalate DietSubjects will consume a low oxalate diet for four days, with blood and 24-hour urine collections occurring at baseline and post diet. A ten day wash out period will follow, during which the subject will consume a self-selected diet. Subjects will then consume the high oxalate diet for the final four days, with blood and 24-hour urine collections once again occurring at baseline and post diet. |
| High Oxalate Diet | Experimental | Dietary Supplement: High Oxalate DietSubjects will consume a high oxalate diet for four days, with blood and 24-hour urine collections occurring at baseline and post diet. A ten day wash out period will follow, during which the subject will consume a self-selected diet. Subjects will then consume the low oxalate diet for the final four days, with blood and 24-hour urine collections once again occurring at baseline and post diet. |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (8 listed)
- Healthy subjects (men and women) between the ages of 18 and 60 years of age
- No calcium oxalate kidney stones or other medical conditions
- Normal comprehensive metabolic panel (CMP)
- Non tobacco users
- Not pregnant
Key exclusion criteria (9 listed)
- Inability to sign and read the informed consent
- Any medical, psychiatric, or social conditions that would prohibit participants from abiding by the study requirements
- Physician refusal
- Pregnant women
- Active medical problems
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Low Oxalate DietParticipants will consume a diet that is controlled in its daily contents of oxalate and calcium, and in its content of carbohydrate, fat, and protein. Participants will be asked not to take any dietary supplements, to exercise strenuously, or to consume food or drink that is not provided to them. | Dietary supplement | Low Oxalate Diet |
| High Oxalate DietParticipants will consume a diet that is controlled in its daily contents of oxalate and calcium, and in its content of carbohydrate, fat, and protein. Participants will be asked not to take any dietary supplements, to exercise strenuously, or to consume food or drink that is not provided to them. | Dietary supplement | High Oxalate Diet |
Primary outcome
Urinary Oxalate Excretion
Time frame: Days 4 and 14
Twenty-four hour urinary oxalate will be reported as mg/day.
Crystalluria
Time frame: Day 4 and 14
Crystalluria will be reported as particles/ml.
Number of Participants With Monocyte Cellular Energetics
Time frame: Days 4 and 14
Cellular energetic oxygen consumption traces will be examined.
1 secondary outcome
Number of Participants With Monocyte Transcriptomics
Time frame: Days 4 and 14
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 26 Jun 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: Yes. Data may be shared with other scientists. All participants information will be de-identified.
Related trials for Kidney Stone
Recruiting
Randomized Controlled Trial of Miniaturized Percutaneous Nephrolithotomy With Vacuum-Assisted Access Sheaths Versus Conventional Sheaths for Treatment of Nephrolithiasis
Kidney Stone
RecruitingPhase 3
Trial to Assess the Efficacy of EMPAgliflozin and Personalized Dietary Counseling for Kidney STONE Prevention
Kidney Stone, Nephrolithiasis
Not yet recruiting
DISS vs FANS in Suction-Assisted RIRS for Medium-Sized Renal Stones
Kidney Stones, Nephrolithiasis
Not yet recruitingObservational study
Novel Antimicrobial Solution to Prevent Infections
Kidney Stone, Infection
RecruitingObservational study
Perioperative Parameter and Treatment Outcomes of ECIRS in Asia
Renal Stone
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Tanecia Mitchell, PhD principal investigator
University of Alabama at Birmingham
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Low Oxalate Diet and High Oxalate Diet in people with Kidney Stone, run by University of Alabama at Birmingham at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 26 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 26 Jun 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Urinary Oxalate Excretion (time frame: Days 4 and 14). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 26 Jun 2026; AzTrials last refreshed its copy on 26 Oct 2026.