Changes in Microbiota and Metabolomic Profile Between Rifaximin Responders and Non-responders In Diarrhoea-Predominant Irritable Bowel Syndrome

Summary

Irritable Bowel Syndrome (IBS) carries a high prevalence worldwide and imposes substantial economic burden on patients, healthcare systems and society. In recent years, dysbiosis of the gut microbiota and bile acid (BA) malabsorption have been identified as putative pathophysiological mechanisms. Bile acid metabolism and gut microbiota are closely related. When patients with IBS-D were compared to healthy subjects, total levels of faecal BAs do not differ, but increased faecal primary BAs and reduced secondary BAs have been repeatedly observed in patients with IBS-D, suggesting abnormal BA deconjugation. Rifaximin, a non-absorbable antibiotic, has been shown in a recent meta-analysis to produce a therapeutic clinical gain compared to other treatment options for IBS, including placebo, paralleled by a high safety profile. It is also now known that changes in fecal microbiota have been observed in patients with IBS who have responded positively to Rifaximin. The relationship between microbiota changes, metabolomics changes after Rifaximin is unclear. There is emerging data to suggest duodenal dysbiosis as a putative pathophysiology, which in one study, clustered together with salivary microbiota than with fecal microbiota. However, the oral microbiome in patients with IBS has never been explored, which could possibly explain the downstream observations of duodenal and fecal dysbiosis. The investigators aim to assess the changes in metabolomic and microbiota profile after Rifaximin treatment, between responders and non-responders. The investigators will also explore the oral microbiome in IBS patients, and assess its relationship with fecal microbiome between responders and non-responders.

Timeline

Start

2018-05-07

Primary completion

2021-08-13

Completion

2021-08-13

Drugs

Indications