Microbiome, antibiotics and irritable bowel syndrome.

INTRODUCTION: Irritable bowel syndrome (IBS) is the most prevalent functional gastrointestinal (GI) disorder. Increasing evidence implicates the GI microbiota in IBS pathogenesis and its modulation represents an emerging therapeutic strategy.

SOURCES OF DATA: Original and review articles were identified through selective searches performed on PubMed and Google Scholar.

AREAS OF AGREEMENT: The role of gut microbiota in IBS is supported by evidence from animal and human studies. Randomized controlled trials demonstrate efficacy of the non-systemic antibiotic rifaximin in reducing IBS symptoms.

AREAS OF CONTROVERSY: Existing studies on microbiota alterations are often inconsistent and limited by the heterogeneity of IBS. The exact mechanism of rifaximin remains to be elucidated. Identifying predictors of response to rifaximin and treatment strategies for symptom recurrence are important clinical questions.

GROWING POINTS: High-throughput molecular methods are leading to rapid advances in our understanding of GI microbiota in IBS AREAS TIMELY FOR DEVELOPING RESEARCH: Future well designed longitudinal studies are required to identify characteristic microbial signatures and potential biomarkers to identify therapeutic targets and predict clinical response.