Diagnostic Performance of Urinary Gluten Immunogenic Peptides in Monitoring the Adherence to Gluten-free Diet.
Condition: Celiac Disease
MeSH terms: Celiac Disease
Study type: Interventional

Summary: 
      The purpose of the GRRES study is to assess the clinical usefulness of urinary gluten
      immunogenic peptides test as a marker of gluten-free diet adherence using the rapid
      immunochromatographic assay based on anti-gliadin 33-mer monoclonal antibodies.
    

Detailed description: 
      A strict and permanent gluten free diet (GFD) is the only effective treatment resulting in
      full clinical, serological and histological remission, avoiding long-term complications in
      celiac disease (CD) patients. Gluten immunogenic peptides (GIP) are fragments of gluten
      proteins resistant to gastrointestinal digestion and detectable in urine after intestinal
      digestion, providing direct evidence of recent gluten ingestion. A significant variability in
      the amount of excreted urinary GIP has been reported in individuals administered with similar
      doses of gluten and, so far, inadequate information is available about the amount of excreted
      GIP in subjects ingesting traces or low amount of gluten. This is an important issue, as even
      a strict GFD could be contaminated by traces of gluten, e.g. in wheat starch and processed
      food. The aim of this study is to assess the clinical usefulness of urinary GIP as a marker
      of GFD adherence using a rapid immunochromatographic assay based on anti-gliadin 33-mer
      monoclonal antibodies. This is a prospective, randomized, triple-blind, placebo-controlled,
      clinical trial. In this study, healthy volunteers following a normal diet will be requested
      to be on strict GFD for 5 days. On day 4th, participants will be requested to collect a
      baseline urine sample and in case of a negative GIP test result they will be assigned to
      ingest a specific dose of purified gluten incorporated in a capsule (0 mg, 10 mg, 50 mg, 100
      mg, 500 mg and 1000 mg, according to randomization). Participants will be requested to
      collect urine samples in a container and take a 5 mL aliquote for the GIP test at the 9th and
      24th hour from the time of the administration of the dose. During the collection, volunteers
      will also be requested to record the volume of the excreted urine and to store the collected
      urine at 4°C. Urine tubes will be stored at -20°C until the quantitative evaluation of GIP.
      GIP test will be performed using the rapid immunochromatographic assay based on anti-gliadin
      33-mer monoclonal antibodies iVYCHECK GIP Urine™ test (Biomedal, Spain) according to the
      manufacturer's instructions.
    

Intervention name(s): Gluten (behaviour); Placebo (behaviour)
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Gluten is a protein normally present in the daily diet of healthy volunteers not suffering from gluten related disorders, in far greater quantities (10-20 g/day) than those used in this study (10 mg-1 g/day).; Placebo is composed of pregelatinized maize starch Ph.Eur. 97.5%; magnesium stearate Ph.Eur. 1.5%; micronized silica Ph.Eur. 0.5%; Micronized talc Ph.Eur. 0.5% (NOT containing preservatives, colorings, or gluten).
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Health Services Research
Keywords: Gluten-free diet; Gluten immunogenic peptides; Gluten contamination; Gluten; Urine