Fecal transplantation may not improve IBS symptoms

Last Updated: 2018-08-21

By Will Boggs MD

NEW YORK (Reuters Health) - Fecal microbiota transplantation (FMT) increases microbial diversity but does not improve symptoms in patients with irritable bowel syndrome (IBS), according to results from a placebo-controlled study.

The microbiome of the gastrointestinal tract is thought to play a role in IBS, and FMT has yielded benefits in other conditions where altered microbial diversity is important.

Dr. Andreas Munk Petersen from Copenhagen University Hospital Hvidovre, in Denmark, and colleagues assessed the effects of FMT in a double-blind, placebo-controlled trial of 52 adult patients with moderate-to-severe IBS. FMT (or placebo) was administered as 25 capsules every morning for 12 days, preceded by a bowel cleansing corresponding to that performed before colonoscopy.

At three months, the placebo group showed a significantly greater improvement in IBS disease severity (as measured by the IBS-severity scoring system, or IBS-SSS) than did the FMT group (mean improvement, 125.71 points vs. 52.45 points; P=0.012).

Eight patients in the FMT group (36.4%) experienced at least 50-point improvements in IBS-SSS score compared with 19 patients in the placebo group (79.2%) at three months, the researchers report in Gut, online August 4.

On average, patients in the placebo group experienced significantly greater improvement in quality of life (16.50 points), compared with patients in the FMT group (7.22 points).

Patients receiving FMT capsules had increases in microbial biodiversity to that matching the fecal donors, whereas placebo patients remained indistinguishable from their pretreatment state.

Microbial diversity did not correlate with IBS-SSS scores.

"No clinical trials have compared FMT delivery routes in IBS, and further trials are needed to determine if a change in delivery route could have an effect on FMT treatment success in these patients," the researchers note.

"There is no evidence for FMT providing symptomatic benefit in patients with IBS in this trial," they conclude. "Although our study shows a better effect of a bowel cleansing than a bowel cleansing followed by FMT treatment on IBS symptoms, we still believe that FMT can be the way forward."

Dr. Stefano Di Bella of the University Hospital of Trieste, Italy, who recently reviewed the role of FMT in inflammatory bowel disease, told Reuters Health by email, "FMT is not a panacea. Increased fecal microbial diversity is not always a synonym of intestinal 'health.'"

"We do not know the pathogenesis of IBS; therefore, the results are not really surprising," said Dr. Di Bella, who was not involved in the study. "The concept of 'dysbiosis' is too generic to be associated with IBS."

He added, "The results of this study could be a starting point to 're-think' the IBS pathogenesis."

Dr. Petersen did not respond to a request for comments.

SOURCE: https://bit.ly/2MoEyWH

Gut 2018.