Exploring gut microbes in adults with IBS and constipation who produce excess methane

Is this trial a fit for you?

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

What this trial studies

This single-center, observational study enrolls adults with IBS (Rome IV) who have predominant constipation, mixed bowel habits, or unspecified type and who show high methane (≥10 ppm) on a glucose breath test. Investigators collect stool and plasma samples to characterize the intestinal microbiota and its relationship to methane production and constipation symptoms. Participants who used antibiotics or probiotics in the past three months are excluded to avoid confounding the microbiota profile. The work aims to map microbial patterns, particularly methanogenic archaea like Methanobrevibacter smithii, in people with methane-associated constipation.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Patient suffering from Irritable Bowel Syndrome (IBS) (abdominal pain for the past 6 months occurring on average at least 1 day per week in the last 3 months, with at least 2 of the following criteria: associated with defecation, associated with a change in stool frequency, associated with a change in stool consistency):

  1. Predominant constipation type (IBS-C): Bristol Stool Scale 1-2 ≥ 25% of the time and Bristol Stool Scale 6-7 ≤ 25% of the time
  2. Alternating diarrhea-constipation type (IBS-M): Bristol Stool Scale 1-2 25% of the time and Bristol Stool Scale 6-7 25% of the time
  3. Unspecified type: absence of sufficient criteria to meet criteria for IBS-C, IBS-D, or IBS-M.
* Patient exhibiting a high methane level (≥ 10 ppm) during a glucose breath test.
* Aged ≥ 18 years at the time of study entry.
* Patient not opposing participation in the study.

Exclusion Criteria:

* Patient who has been treated with antibiotics or probiotics in the last 3 months prior to inclusion.
* Patient suffering from diarrhea-predominant IBS (Bristol Stool Scale 6-7 ≥ 25% of the time and Bristol Stool Scale 1-2 ≤ 25% of the time).
* Patient with a history of abdominal surgery other than appendectomy and cholecystectomy.
* Patient with a history of celiac disease.
* Patient with proven inflammatory bowel disease.
* Patient with a history of colorectal cancer.
* Patient with uncontrolled hypothyroidism.
* Patient with uncontrolled diabetes.
* Pregnant or breastfeeding women.
* Patient deprived of liberty by a judicial or administrative decision.
* Adult patient under legal protection (guardianship, curators).
* Patient unable to discontinue proton pump inhibitor treatment during the study period

Where it's running

• Hôpital Edouard Herriot
  Lyon, France Recruiting

Study contacts

• Study coordinator: François MION, Pr
• Email: francois.mion@chu-lyon.fr
• Phone: 4 72 11 01 36

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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.