Fecal Microbiota Transplantation for Gastrointestinal Disorders

Thomas Malikowski; Sahil Khanna; Darrell S. Pardi


Curr Opin Gastroenterol. 2017;33(1):8-13. 

In This Article

Irritable Bowel Syndrome

IBS is a common gastrointestinal disorder characterized by abdominal pain and altered bowel habits. Prevalence in the general population is remarkably high at 10–15%.[24] The etiology of this disorder is incompletely understood, although many factors, including alterations in the microbiome, have been implicated in both development and exacerbation of IBS.

Evidence supports that the microbiome is significantly altered in patients with IBS when compared with normal patients. Microbial diversity is decreased in IBS, with diminished amounts of Lactobacilli and Bifidobacteria, while aerobes and mucosal bacteria are more abundant than in the normal gut.[25,26] Studies have also shown specific alterations of the gut microbiome in patients with constipation predominant-IBS and STC.[27,28] In the gut of patients with constipation-predominant IBS, sulphate producing bacteria are increased, and lactate producing bacteria are decreased.[29] Interestingly, IBS may develop following infection or treatment with broad spectrum antibiotics, supporting the assertion that altered microbial characteristics may impact development of the disorder.[30]

Interactions between microbes and the host that impact gut motility and visceral sensitivity are postulated as mechanisms linking dysbiosis to IBS symptomatology. Several experimental studies have shown bacteria to impact gut motility through paracrine interactions with smooth muscle cells in the gut wall.[31–34] Additional studies have shown bacteria to impact pain perception by altering molecular receptors in the intestinal epithelium. As an example, Lactobacillus acidophilus cultures have been shown to induce opioid and cannabinoid receptors in the intestinal epithelium.[35] Hydrogen sulfide produced by microbes has also been implicated as a neuromodulatory agent capable of altering visceral sensation.[36]

Given the promise of microbial manipulation with probiotics and antibiotics as a therapy for IBS, FMT has been considered as an additional option. A few small studies have demonstrated benefit of FMT. In a dated study conducted in 1989 by Borody et al.,[37] 55 patients with IBS received FMT via enema, with 20 (36%) achieving complete resolution of symptoms, six achieving partial relief, and 26 achieving no relief. This study did not exclude patients with IBD or C. difficile infection. Subsequently, in an uncontrolled study conducted in 2014 by Pinn et al.,[38] 13 patients with constipation, diarrhea, and mixed predominant IBS received FMT via endoscopic delivery to the distal duodenum, with 70% experiencing improvement in symptoms. In addition, there is some evidence to support the use of FMT for STC. In one study by Tian et al.,[15] 24 patients with STC received FMT via nasojejunal tube for three straight days and were then followed for 12 weeks. FMT successfully increased the number of mean bowel movements per week from 1.8 to 4.1 (P < 0.01) and reduced mean Wexner constipation scores at 12 weeks from 14.1 to 7.5 (P < 0.01). A second study by Ge et al.[39] showed similar benefit. Twenty-one patients with STC were included and also received FMT for three consecutive days via nasojejunal tube along with daily soluble dietary fiber at a dose of 8 g twice daily. After 12 weeks, mean stool frequency increased from 1.7 to 4.8 (P < 0.05), and there was improvement of mean constipation symptom scores (PAC-SYM) from 2.0 to 1.5 (<0.05).

Taken as a whole, the evidence for microbial manipulation and FMT for IBS and STC are promising, but clinicians should exercise caution in applying it to current practice. Large randomized, double-blinded placebo controlled studies are needed before incorporating such therapies in the routine management of IBS and STC. Furthermore, clarification regarding the optimal administration methods and dosing is needed. Upon review of clinicaltrials.gov there are multiple studies underway, including randomized controlled trials, evaluating the efficacy of FMT for treatment of IBS and STC.