Limited, low-quality data suggest fecal transplant is ineffective for patients with irritable bowel syndrome

Reference

Xu D, Chen VL, Steiner CA, et al. Efficacy of fecal microbiota transplantation in irritable bowel syndrome: a systematic review and meta-analysis. Am J Gastroenterol 2019;114(7):1043-1050.

Synopsis

These authors searched several databases to identify randomized trials that compared fecal transplant with placebo treatment in patients older than 16 years with IBS. Additionally, they hand-searched bibliographies from conferences and the reference lists of included studies. Two authors independently assessed studies for inclusion and evaluated the methodologic quality of the included studies. The authors don't describe how they reconciled disagreements. They ultimately included only 4 studies with 254 patients. Two of the studies have not yet been fully published and were only available in abstract form. All used the ROME III criteria for the diagnosis of IBS. One study administered the transplant via colonoscopy, one via nasojejunal tube, and 2 via oral capsules. One of the studies was at low risk of bias and the other 3 were of uncertain risk of bias (my hunch is that these 3 were not low risk!). Two studies reported global improvement in the placebo-treated patients and 2 reported global improvement in the transplant-treated patients; pooling resulted in no net effect. The 2 studies that showed global deterioration used oral capsules (number needed to treat to harm = 3; 95% CI 2 - 10). Two studies reported an improvement in quality of life during the first 12 weeks following treatment, but not afterward. The authors did a bunch of subgroup analyses, but they seem rather silly given the small number of patients and the uncertain study quality.