Overview

40 subjects with a confirmed diagnosis of IBD or >6 months post-RYGB with a diagnosed USD event or kidney stone on imaging within the past three years and 40 healthy controls will be administered a high oxalate diet on Days 0-3 and Days 21-24 with a washout period on Days 4-7 and will be administered 250mg sodium oxalate on Days 8-20, via prepared spinach, from Weil Cornell Medicine's Clinical and Translational Science Center. Subjects will partake in four stool collections, four 24-h urine collections, two blood collections, and four sets of colonic permeability testing.

Eligibility

Inclusion Criteria:

        In order to be eligible to participate in this study, an individual must meet all of the
        following criteria:
          -  Subjects > 18 years and < 80 years of age
          -  a confirmed diagnosis of IBD or > 6 months post- RYGB, with a diagnosis USD event
             (renal colic with spontaneous stone passage, emergency room visits, or urological
             interventions) or have kidney stone on imaging (CT, MRI, or US) in the previous three
             years.
          -  We will include all racial and ethnic groups, and both men and women.
        In order to be eligible in this study as a healthy control, an individual must meet all of
        the following criteria:
          -  Subjects > 18 years and < 80 years of age
          -  Healthy controls with no chronic diseases, not on any chronic medications, no history
             of GI pathology, or urinary stone disease (USD).
          -  We will include all racial and ethnic groups, and both men and women.
        Exclusion Criteria:
        An individual who meets any of the following criteria will be excluded from participation
        in this study:
          -  pregnant or nursing women and people with any medical, psychiatric, debilitating
             disease/disorder or social condition that, in the judgment of the investigator, would
             interfere with or serve as a contraindication to adherence to the study protocol,
             ability to give ICF or complete the protocol.
          -  subjects with total and partial colectomy.
          -  subjects who received oral, intramuscular, or intravenous antibiotics within three
             months before screening.
          -  Patients with perianal disease usually receive recurrent antibiotics and, therefore,
             will be excluded from the study.
          -  patients with an ongoing symptomatic IBD flare or a flare within the previous three
             months
          -  patients with estimated glomerular filtration rates (eGFR) < 60 ml/min/1.73 m2
             calculated by the CKD-EPI equation measured anytime within the preceding year.
        An individual who meets any of the following criteria will be excluded from participation
        in this study as a healthy control:
          -  pregnant or nursing women and people with any medical, psychiatric, debilitating
             disease/disorder or social condition that, in the judgment of the investigator, would
             interfere with or serve as a contraindication to adherence to the study protocol,
             ability to give ICF or complete the protocol.
          -  subjects with total and partial colectomy.
          -  subjects who received oral, intramuscular, or intravenous antibiotics within three
             months before screening.
          -  Patients with perianal disease usually receive recurrent antibiotics and, therefore,
             will be excluded from the study.
          -  patients with an ongoing symptomatic IBD flare or a flare within the previous three
             months
          -  patients with estimated glomerular filtration rates (eGFR) < 60 ml/min/1.73 m2
             calculated by the CKD-EPI equation measured anytime within the preceding year.