Inflammatory Bowel Diseases (IBD)
The research results so far show that inflammatory bowel diseases (IBD) may be a potential future indication for fecal microbiota transplantation (FMT). As the name suggests, they are characterized by recurrent inflammation, including ulcerative colitis (UC) and Crohn’s disease (CD).
Reduced bacterial diversity was noted in both diseases, in particular a reduction in the Bacteroidetes and Firmicutes. It has not been verified whether disturbances in the composition of the microbiota are the cause or the effect of the disease, but preliminary studies have indicated that the microbiota may play a role in the pathogenesis of IBD. Scientists continue clinical trials with the hope that FMT will become the standard treatment for inflammatory bowel disease.
The role of a healthy and diversified microbiota is to help maintain the integrity of the intestinal barrier, support functions of the immune system, and to prevent the development of undesirable microorganisms. The appropriate microenvironment and increased secretion of short-chain fatty acids formed during fermentation in the intestines allow it to maintain its tightness and prevent the penetration of pathogens. In addition, FMT is believed to restore proper bacterial diversity, and this modulate the activity of T lymphocytes and other white blood cells.
Ulcerative colitis
Genetic and environmental factors influence the development of UC. There is a reduced number of goblet cells responsible for mucin production and NOD-like NLRP6 receptors involved in inflammatory responses. The permeability of the intestinal mucosa increases, causing inflammation in the rectum and other parts of the colon.
The undeniable combination of the intestinal microbiota with the pathogenesis of UC has increased the interest of scientists in alternative treatment methods, including using probiotics or fecal microbiota transplantation. The first results of FMT studies in ulcerative colitis did not show as much efficacy as in the treatment of C. difficile (approx. 90% effectiveness), but the researchers were optimistic for further research. In some studies, up to half of the respondents achieved and maintained remission after FMT. At the same time, an increase in Eubacterium hallii, Roseburia inulinivorans and enhanced production of protective short-chain fatty acids (SCFA) and bile acids was observed. In addition, more strains of Fusobacterium gonidiaformans, Sutterella wadsworthensis, and species of the genus Escherichia have been identified in patients with persistent symptoms. The research presented so far has been significantly heterogenous, therefore it is necessary to continue well-planned research into the effectiveness of FMT treatment in UC.
Crohn’s Disease
This disease manifests with characteristic inflammatory lesions throughout the digestive system, from the mouth to the rectum. Crohn’s disease develops due to a genetic predisposition or environmental factors in combination with altered gut microbiota. The most common symptoms are diarrhea, pain, rectal bleeding, fever, weight loss, and fatigue. Corticosteroids, biological drugs (monoclonal antibodies), and immunomodulators (thiopurines and methotrexate) are used to relieve symptoms and bring the disease into remission. The quality of life of patients with Crohn’s disease is low, so researchers try FMT as an alternative treatment, which has shown promising results. In one of the most extensive studies, symptom remission after FMT was achieved in 57% of patients. In addition, it was shown that performing another FMT after four months allowed for maintaining the condition after the first FMT. Crohn’s disease is more complex than UC and may require additional criteria when planning and conducting FMT efficacy studies.
Adverse reactions occurring in patients after FMT in inflammatory bowel disease were moderate-intensity and usually resolved spontaneously. Research shows that FMT is a safe form of therapy that can benefit patients with Crohn’s disease and ulcerative colitis. However, inflammatory bowel diseases require ongoing treatment; while FMT may be hope for stable remission, it is necessary to plan research and summarize all effects adequately.
References
Wortelboer, K., Nieuwdorp, M., & Herrema, H. (2019). Fecal microbiota transplantation beyond Clostridioides difficile infections. EBioMedicine, 44, 716–729. https://doi.org/10.1016/j.ebiom.2019.05.066
Green, J. E., Davis, J. A., Berk, M., Hair, C., Loughman, A., Castle, D., Athan, E., Nierenberg, A. A., Cryan, J. F., Jacka, F., & Marx, W. (2020). Efficacy and safety of fecal microbiota transplantation for the treatment of diseases other than Clostridium difficile infection: a systematic review and meta-analysis. Gut microbes, 12(1), 1–25. https://doi.org/10.1080/19490976.2020.1854640
Allegretti JR, Mullish BH, Kelly C, Fischer M. The evolution of the use of faecal microbiota transplantation and emerging therapeutic indications. Lancet. 2019 Aug 3;394(10196):420-431. doi: 10.1016/S0140-6736(19)31266-8. PMID: 31379333.
Shen, Z. H., Zhu, C. X., Quan, Y. S., Yang, Z. Y., Wu, S., Luo, W. W., Tan, B., & Wang, X. Y. (2018). Relationship between intestinal microbiota and ulcerative colitis: Mechanisms and clinical application of probiotics and fecal microbiota transplantation. World journal of gastroenterology, 24(1), 5–14. https://doi.org/10.3748/wjg.v24.i1.5
Veauthier B, Hornecker JR. Crohn’s Disease: Diagnosis and Management. Am Fam Physician. 2018 Dec 1;98(11):661-669. PMID: 30485038.
Wang, H., Cui, B., Li, Q. et al. The Safety of Fecal Microbiota Transplantation for Crohn’s Disease: Findings from A Long-Term Study. Adv Ther 35, 1935–1944 (2018). https://doi.org/10.1007/s12325-018-0800-3
Sudarshan Paramsothy, Ramesh Paramsothy, David T Rubin, Michael A. Kamm, Nadeem O. Kaakoush, Hazel M Mitchell, Natalia Castaño-Rodríguez, Faecal Microbiota Transplantation for Inflammatory Bowel Disease: A Systematic Review and Meta-analysis, Journal of Crohn’s and Colitis, Volume 11, Issue 10, October 2017, Pages 1180–1199, https://doi.org/10.1093/ecco-jcc/jjx063
