The human body is inhabited by a complex community of microbes, collectively referred to as “microbiota”. A vast majority of these bacteria are found in the gastrointestinal tract, sometimes released along with stool or attached to the intestinal lining. Current research suggests that changes in the gut bacteria may be involved in different gastrointestinal diseases.

This study is being conducted to understand the behavior and influence of intestinal microbiota in different gastrointestinal diseases, such as Celiac Disease, Irritable bowel syndrome (IBS), Crohn´s disease and Ulcerative colitis


Who is eligible to participate?

  • Adult patients between 18-75 years old.
  • Diagnosed with one of the following diseases:
    • Celiac disease, with active symptoms and/or following a gluten containing diet
    • Irritable bowel syndrome (IBS).
    • Crohn’s disease or Ulcerative colitis with active symptoms.
  • Healthy volunteer.


What will the study measure?

  • Gastrointestinal symptoms, general health and wellbeing scores, using questionnaires.
  • If diagnosis of celiac disease: presence of celiac disease genes, assessed by a genetic test., as well as specific markers for celiac disease.


Will there be any samples being collected?

  • One stool sample
  • Blood sample (optional)
  • Biopsies (optional) if you are scheduled for endoscopy


What is the total duration of the study?

This research study lasts the same time as your regular endoscopy appointment.


Will there be a compensation to participate?

We will offer compensation, as well as parking ticket for offering your time participating in the study.

If you think you can be eligible for this study, please contact us, we will be happy to hear from you!


Contact us to know further information about the study:

Gaston Rueda, MD – Clinical Research Fellow:

Pedro Miranda, PhD:



Dr. Premysl Bercik (Principal Investigator), Dr. Gaston Rueda (research staff), Dr Pedro Miranda (research staff), Dr Andrea Nardelli, Caroline Seiler (research staff), Carolina Duque (research staff).

The study has been approved by Hamilton Integrated Research Ethics Board – Study #:12-599-T

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