Transplantation of fecal microbiota was found to result in alterations in gut microbiota, but it was not found to improve quality of life or alleviate symptoms better than placebo in patients with irritable bowel syndrome (IBS), according to a study published in Gut.

A group of investigators in Denmark conducted a randomized, double-blind, placebo-controlled analysis to determine if fecal microbiota transplantation can result in gut microbiota changes and improve symptoms in patients with IBS. 

The researchers recruited patients with moderate to severe IBS between the ages of 18 and 60 years and separated them into 3 groups based on IBS classifications: constipation-predominant IBS (IBS-C), diarrhea-predominant IBS (IBS-D), or alterations between constipation and diarrhea (IBS-M). In addition, the researchers included 4 fecal contributors (aged between 18 and 45 years).

Continue Reading

A total of 52 participants were included in the study and randomly assigned to receive either placebo or fecal transplant for 12 days and then monitored at 1, 3, and 6 months. Upon arrival, patients self-reported symptoms using IBS-severity scoring and IBS-specific quality of life systems; fecal samples were also collected upon each visit.

After month 3, the investigators reported statistically significant improvements for both IBS-severity scores and quality of life for patients in the placebo cohort. Patients in the fecal microbiota transplant cohort had greater microbiota biodiversity than patients in the placebo cohort.

The majority of both fecal transplant and placebo participants experienced adverse effects (84.6% and 57.7%, respectively).

Related Articles

“There is no evidence for [fecal microbiota transplantation] providing symptomatic benefit in patients with IBS in this trial,” the authors wrote. “No significant side effects to FMT were observed during 6 months follow-up.”

“However, more studies are required to examine the potential role of [fecal microbiota transplantation] in treating IBS,” they concluded.


Halkjær SI, Christensen AH, Lo BZS, et al. Faecal microbiota transplantation alters gut microbiota in patients with irritable bowel syndrome: results from a randomised, double-blind placebo-controlled study [published online July 6, 2018]. Gut. doi:10.1136/gutjnl-2018-316434