Gut microbiome in post-infectious irritable bowel syndrome

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 is a prospective, multicenter observational study that will use whole‑genome shotgun sequencing to profile the gut microbiome in 315 adults divided equally into three groups: PI‑IBS patients, post‑infectious individuals without IBS, and healthy controls. PI‑IBS patients will complete baseline clinical assessments including IBS‑SSS and provide stool samples at baseline and monthly for three months, while control participants provide a single baseline sample. All samples will be processed under standardized conditions and analyzed centrally to identify reproducible microbial signatures and taxa linked to disease presence and symptom severity. The study represents the first aim of a broader program to inform precision microbiome modulation strategies for PI‑IBS.

Why it matters

Who can join: the full rules

PI-IBS patients (n = 105)

* Inclusion criteria

  * Age ≥ 18 years old
  * PI-IBS diagnosed according to Rome IV criteria (33).
  * Diagnosis no earlier than 3 months before enrollment.
  * Written informed consent and compliance with study procedures.
* Exclusion criteria

  * Chronic organic gastrointestinal (GI) disorders (e.g. Inflammatory Bowel Disease -IBD), metabolic syndrome, obesity, diabetes, GI cancers, systemic autoimmune disorders.
  * History of major abdominal surgery.

Control cohort #1 - Post-infectious non-IBS (n = 105)

* Inclusion criteria

  * Age ≥ 18 years old
  * History of acute infectious gastroenteritis \>6 months before enrollment.
  * Complete recovery without persistent GI symptoms.
* Exclusion criteria

  * Current or past diagnosis of IBS.
  * Any chronic GI or systemic disorders.

Control cohort #2 - Healthy subjects (n = 105)

* Inclusion criteria

  * Age ≥ 18 years old
  * Healthy donors from FMT program or blood donor program.
  * No history of GI or systemic disorders.
* Exclusion criteria

  * Any GI or systemic chronic condition.
  * Recent antibiotics/probiotics (\<4 weeks).
  * Chronic medication affecting microbiome composition (e.g. PPI)

Where it's running

• Digestive Disease Center, Fondazione Policlinico Univesitario A. Gemelli IRCCS
  Rome, Italy Recruiting

Study contacts

• Principal investigator: Gianluca Ianiro — Fondazione Policlinico Universitario Agostino Gemelli IRCCS
• Study coordinator: Gianluca Ianiro
• Email: gianluca.ianiro@policlinicogemelli.it
• Phone: +390630155701

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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.