A review study finds that fecal microbiota transplant (FMT) is not an effective treatment for “global” IBS symptoms. The study looked at 4 investigations of FMT as a viable treatment for IBS and included 254 participants. In looking at the results of all 4 studies, no significant improvements in IBS symptoms was observed when administering FMT over a 12-week period when compared to placebo. American Journal of Gastroenterology
Takeaway: When you slice up the IBS pie, you see multiple different conditions that are causing symptoms – from stress and food allergies to undiagnosed colitis and microbial discord. But there is a clear subset within IBS called post-infectious IBS – this group includes people who have received lots of antibiotics and subsequently suffer from dysbiosis (gut bacteria imbalance).
To find appropriate IBS candidates for FMT, the key is to look not just at the determining criteria for having IBS, but to look beyond these criteria and see what the catalyst was – or the root cause of the IBS. Is dysbiosis the likely reason behind the IBS? If so, those are the patients that should be considered for FMT, not simply all patients with IBS. Bottom line, a dysbiotic origin of IBS is more predictive of FMT as a viable cure. This is the subset of patients where IBS-FMT research should be focused.
In addition, adding dietary change as an intervention along with the FMT in those who have dysbiosis as the root cause of their IBS would most likely result in greater response rates to the FMT treatment. The beneficial bacteria provided during the fecal transplant can only take root if the dietary components (fiber primarily) are there to feed the bacteria and encourage proliferation and lasting colonization in the gut.