Informed Therapeutic Microbiome Modulation for Post-Infectious Irritable Bowel Syndrome: Pilot Experience of a Microbiome Clinic

William Fusco; Flavio De Maio; Serena Porcari; Andrea Severino; Daniele Salvi; Stefania Piccirelli; Clarissa Ferrari; Antonio Sibilla; Gianluca Quaranta; Luca Masucci; Giovanni Cammarota; Maurizio Sanguinetti; Antonio Gasbarrini; Gianluca Ianiro

doi:10.3390/nu18030490

Informed Therapeutic Microbiome Modulation for Post-Infectious Irritable Bowel Syndrome: Pilot Experience of a Microbiome Clinic

Nutrients. 2026 Feb 2;18(3):490. doi: 10.3390/nu18030490.

Authors

William Fusco¹, Flavio De Maio², Serena Porcari³, Andrea Severino³, Daniele Salvi⁴, Stefania Piccirelli⁴, Clarissa Ferrari⁴, Antonio Sibilla¹, Gianluca Quaranta², Luca Masucci², Giovanni Cammarota^{1

5}, Maurizio Sanguinetti², Antonio Gasbarrini^{1

3}, Gianluca Ianiro^{1

3}

Affiliations

¹ Department of Translational Medicine and Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy.
² Department of Laboratory and Infectious Sciences, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy.
³ Department of Medical and Surgical Sciences, UOC CEMAD Centro Malattie dell'Apparato Digerente, Medicina Interna e Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy.
⁴ Department of Gastroenterology and Endoscopy, Fondazione Poliambulanza Istituto Ospedaliero, 25124 Brescia, Italy.
⁵ Department of Medical and Surgical Sciences, UOC Gastroenterologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy.

Abstract

Background: Untargeted microbiome modulation has achieved conflicting results in post-infectious irritable bowel syndrome (PI-IBS). Methods: In a case-control study of PI-IBS patients, cases received targeted microbial modulation informed by microbiome profiling, while controls were managed by standard therapy. Treatment response was defined as a decrease in IBS-symptom severity scale (IBS-SSS) ≥50 points. Results: All thirteen cases (100%) and 11/20 controls (55%) experienced treatment response (p < 0.0001). The mean IBS-SSS score after treatments was 163 in cases and 231 in controls (p = 0.01). Conclusions: Based on our preliminary results, therapeutic microbiome modulation might be a promising strategy for PI-IBS. Further studies are needed to clarify its role.

Keywords: irritable bowel syndrome; microbiome; personalized medicine; precision medicine.

MeSH terms

Adult
Case-Control Studies
Female
Gastrointestinal Microbiome*
Humans
Irritable Bowel Syndrome* / etiology
Irritable Bowel Syndrome* / microbiology
Irritable Bowel Syndrome* / therapy
Male
Middle Aged
Pilot Projects
Severity of Illness Index
Treatment Outcome