Clinical trial Recruiting at 1 site Interventional Ages 18 to 130

Understanding how diet and sex affect kidney stone risk after bariatric surgery

Official title: Gut Microbiome and Sex as Risk Factors for Kidney Stones After Bariatric Surgery

Run by University of Chicago · NCT04590690 · Data updated 2026-11-12

This study tests how diet and gender affect the chances of getting kidney stones in people who have weight loss surgery.

More Bariatric Surgery Candidate trials

Quick facts

Study typeInterventional
Ages18 Years to 130 Years
SexAll
Enrollment28 (estimated)
SponsorUniversity of Chicago
Academic / other
Locations1 site (Chicago, Illinois)
StatusRecruiting
StartedNovember 1, 2020
Main results expectedMarch 1, 2027
Study endsMay 1, 2027
Registry record updatedMay 11, 2026
Trial IDNCT04590690 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are individuals approved for bariatric surgery without a history of kidney stones or renal impairment.

Probably not a fit

Patients with primary renal diseases, renal impairment, or known bladder voiding problems may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This study investigates the impact of diet and sex on the risk of developing kidney stones in individuals undergoing gastric bypass surgery. Participants will follow a specialized diet for six days and attend three study visits at the University of Chicago Medical Center. The research will analyze urine supersaturation levels and the correlation of gut microbiome species with urine oxalate levels. The study aims to identify sex differences in kidney stone risk among bariatric surgery candidates.

Why it matters

Potential benefit: If successful, this study could help identify dietary and biological factors that reduce the risk of kidney stones in bariatric surgery patients.

How similar studies have gone: Other studies have explored the relationship between diet and kidney stones, but this specific approach focusing on bariatric surgery candidates is relatively novel.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Participants without history of stone disease, family history of stone disease
* Participants pre-bariatric surgery who are approved and planned for surgery in the Bariatric Surgery Center at University of Chicago Medicine.

Exclusion Criteria:

* Patients with primary renal diseases or renal impairment (eGFR \< 90)
* Patients with known bladder voiding problems
* Patients with 25-vitamine D deficiency, as defined by level \< 25ng/mL

Where it's running

  • University of Chicago Medical Center
    Chicago, Illinois, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.