Fecal microbiota transplant
Fecal microbiota transplant (FMT), also known as a stool transplant, is the process of transferring fecal bacteria and other microbes from a healthy individual into another individual. FMT is an effective treatment for Clostridioides difficile infection (CDI). For recurrent CDI, FMT is more effective than vancomycin.
|Fecal microbiota transplant|
Escherichia coli at 10,000× magnification
|Other names||Fecal bacteriotherapy, fecal transfusion, fecal transplant, stool transplant|
Side effects may include a risk of infections, therefore the donor should be screened. FMT involves restoration of the colonic microflora by introducing healthy bacterial flora through infusion of stool via colonoscopy, enema, orogastric tube, or by mouth in the form of a capsule containing feces from a healthy donor, which in some cases is freeze-dried.
With CDI becoming more common, FMT is gaining increasing prominence, with some experts calling for it to become the first-line therapy for CDI. FMT has been used experimentally to treat other gastrointestinal diseases, including colitis, constipation, irritable bowel syndrome, and neurological conditions, such as multiple sclerosis and Parkinson's. In the United States, human feces has been regulated as an experimental drug since 2013. In the United Kingdom, FMT regulation is under the remit of the Medicines and Healthcare products Regulatory Agency.
Clostridioides difficile infectionEdit
Fecal microbiota transplant is approximately 85–90% effective in people with CDI for whom antibiotics have not worked or in whom the disease recurs following antibiotics. Most people with CDI recover with one FMT treatment.
A 2009 study found that fecal microbiota transplant was an effective and simple procedure that was more cost-effective than continued antibiotic administration and reduced the incidence of antibiotic resistance.
Once considered to be a "last resort therapy" by some medical professionals, due to its unusual nature and invasiveness compared with antibiotics, perceived potential risk of infection transmission, and lack of Medicare coverage for donor stool, position statements by specialists in infectious diseases and other societies have been moving toward acceptance of FMT as a standard therapy for relapsing CDI and also Medicare coverage in the United States.
In May 1988, Australian professor Thomas Borody treated the first ulcerative colitis patient using FMT, which led to longstanding symptom resolution. Following on from that, Justin D. Bennet published the first case report documenting reversal of Bennet's own colitis using FMT. While C. difficile is easily eradicated with a single FMT infusion, this generally appears to not be the case with ulcerative colitis. Published experience of ulcerative colitis treatment with FMT largely shows that multiple and recurrent infusions are required to achieve prolonged remission or cure.
Adverse effects were poorly understood as of 2016. They have included bacterial blood infections, fever, SIRS-like syndrome, exacerbation of inflammatory bowel disease in people who also had that condition, and mild GI distress which generally resolve themselves soon after the procedure, including flatulence, diarrhea, irregular bowel movements, abdominal distension/bloating, abdominal pain/tenderness, constipation, cramping, and nausea. There are also concerns that it may spread COVID-19.
A person died in the United States in 2019 after receiving an FMT that contained drug-resistant bacteria and another person who received the same transplant was also infected. The FDA issued a warning against potentially life-threatening consequences of transplanting material from improperly screened donors.
There are evidence-based consensus guidelines for the optimal administration of FMT. Such documents outline the FMT procedure, including preparation of material, donor selection and screening, and FMT administration.
The gut microbiota comprises all microorganisms that reside along the gastrointestinal tract, including commensal, symbiotic and pathogenic organisms. FMT is the transfer of fecal material containing bacteria and natural antibacterials from a healthy individual into a diseased recipient.
Preparing for the procedure requires careful selection and screening of the potential donor. Close relatives are often chosen on account of ease of screening; however, in the case of treatment of active C. diff., family members and intimate contacts may be more prone to be carriers themselves. This screening involves medical history questionnaires, screening for various chronic medical diseases (e.g. irritable bowel diseases, Crohn's disease, gastrointestinal cancer, etc.), and laboratory testing for pathogenic gastrointestinal infections (e.g. CMV, C. diff., salmonella, Giardia, GI parasites, etc.).
No laboratory standards have been agreed upon, so recommendations vary for size of sample to be prepared, ranging from 30 to 100 grams (1.1 to 3.5 ounces) of fecal material for effective treatment. Fresh stool is used to increase viability of bacteria within the stool and samples are prepared within 6–8 hours. The sample is then diluted with 2.5–5 times the volume of the sample with either normal saline, sterile water, or 4% milk. Some locations mix the sample and the solvent with a mortar and pestle, and others use a blender. There is concern with blender use on account of the introduction of air which may decrease efficacy as well as aerosolization of the feces contaminating the preparation area. The suspension is then strained through a filter and transferred to an administration container. If the suspension is to be used later, it can be frozen after being diluted with 10% glycerol, and used without loss of efficacy compared to the fresh sample. The fecal transplant material is then prepared and administered in a clinical environment to ensure that precautions are taken.
Mechanism of actionEdit
One hypothesis behind fecal microbiota transplant rests on the concept of bacterial interference, i.e., using harmless bacteria to displace pathogenic organisms, such as by competitive niche exclusion. In the case of CDI, the C. difficile pathogen is identifiable. Recently, in a pilot study of five patients, sterile fecal filtrate was demonstrated to be of comparable efficacy to conventional FMT in the treatment of recurrent CDI. The conclusion from this study was that soluble filtrate components (such as bacteriophages, metabolites, and/or bacterial components, such as enzymes) may be the key mediators of FMT's efficacy, rather than intact bacteria. It has now been demonstrated that the short-chain fatty acid valerate is restored in human fecal samples from CDI patients and a bioreactor model of recurrent CDI by FMT, but not by antibiotic cessation alone; as such, this may be a key mediator of FMT's efficacy. Other studies have identified rapid-onset but well-maintained changes in the gut bacteriophage profile after successful FMT (with colonisation of the recipient with donor bacteriophages), and this is therefore another key area of interest.
In contrast, in the case of other conditions such as ulcerative colitis, no single culprit has yet been identified. However, analysis of gut microbiome and metabonome changes after FMT as treatment for ulcerative colitis has identified some possible candidates of interest.
The concept of treating colon diseases with fecal matter originated in India. Charak Samhita and many other ancient Ayurveda text that date back to more than 3,000 years recommend intake of cow dung and cow urine for multiple stomach-related disorders. Fourth-century Chinese medical literature also mentions use of fecal matter to treat food poisoning and severe diarrhea. Twelve hundred years later Ming dynasty physician Li Shizhen used "yellow soup" (aka "golden syrup") which contained fresh, dry or fermented stool to treat abdominal diseases. "Yellow soup" was made of fecal matter and water, which was drunk by the person.
The consumption of "fresh, warm camel feces" has also been recommended by Bedouins as a remedy for bacterial dysentery; its efficacy probably attributable to the antimicrobial subtilisin produced by Bacillus subtilis was anecdotally confirmed by German soldiers of the Afrika Korps during World War II.
The first use of FMT in western medicine was published in 1958 by Ben Eiseman and colleagues, a team of surgeons from Colorado, who treated four critically ill people with fulminant pseudomembranous colitis (before C. difficile was the known cause) using fecal enemas, which resulted in a rapid return to health. For over two decades, FMT has been provided as a treatment option at the Centre for Digestive Diseases in Five Dock, by Thomas Borody, the modern-day proponent of FMT. In May 1988 their group treated the first ulcerative colitis patient using FMT, which resulted in complete resolution of all signs and symptoms long term. In 1989 they treated a total of 55 patients with constipation, diarrhea, abdominal pain, ulcerative colitis, and Crohn's disease with FMT. After FMT, 20 patients were considered "cured" and a further 9 patients had a reduction in symptoms. Stool transplants are considered about 90 percent effective in those with severe cases of Clostridium difficile colonization, in whom antibiotics have not worked.
The first randomized controlled trial in Clostridium difficile infection was published in January 2013. The study was stopped early due to the effectiveness of FMT, with 81% of patients achieving cure after a single infusion and over 90% achieving a cure after a second infusion.
Since that time various institutions have offered FMT as a therapeutic option for a variety of conditions.
Society and cultureEdit
Interest in FMT grew in 2012 and 2013, as measured by the number of clinical trials and scientific publications.
In the United States, the FDA announced in February 2013 that it would hold a public meeting entitled "Fecal Microbiota for Transplantation" which was held on May 2–3, 2013. In May 2013 the FDA also announced that it had been regulating human fecal material as a drug. The American Gastroenterological Association (AGA), the American College of Gastroenterology (ACG), the American Society for Gastrointestinal Endoscopy (ASGE), and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) sought clarification, and the FDA Center for Biologics Evaluation and Research (CBER) stated that FMT falls within the definition of a biological product as defined in the Public Health Service Act and the definition of a drug within the meaning of the Federal Food, Drug, and Cosmetic Act. It argued since FMT is used to prevent, treat, or cure a disease or condition, and intended to affect the structure or any function of the body, "a product for such use" would require an Investigational New Drug (IND) application.
In July 2013, the FDA issued an enforcement policy ("guidance") regarding the IND requirement for using FMT to treat C. difficile infection unresponsive to standard therapies (78 FR 42965, July 18, 2013).
In March 2014, the FDA issued a proposed update (called "draft guidance") that, when finalized, is intended to supersede the July 2013 enforcement policy for FMT to treat C. difficile infections unresponsive to standard therapies. It proposed an interim discretionary enforcement period, if 1) informed consent is used, mentioning investigational aspect and risks, 2) stool donor is known to either the person with the condition or physician, and 3) stool donor and stool are screened and tested under the direction of the physician (79 FR 10814, February 26, 2014). Some doctors and people who want to use FMT have been worried that the proposal, if finalized, would shutter the handful of stool banks which have sprung up, using anonymous donors and ship to providers hundreds of miles away.
The FDA has issued three safety alerts regarding the transmission of pathogens. The first safety alert, issued in June 2019, described the transmission of a multidrug resistant organism from a donor stool that resulted in the death of one person. The second safety alert, issued in March 2020, was regarding FMT produced from improperly tested donor stools from a stool bank which resulted in several people hospitalizations and two deaths. A safety alert in late March, 2020, was due to concerns of transmission of COVID-19 in donor stool. To date, there are no FDA-approved FMT products available in the United States.
In 2017, a group of ME-CFS patients set up the first microbiota Superdonor stool bank , due to the lack of treatments for the disease, focusing only in superdonors and high quality microbiota solutions.
Across Europe, numerous stool banks have emerged to serve the increasing demand. While consensus rapports exists, standard operation procedures still differ. Institutions in the Netherlands have published their protocols for managing FMT, and in Denmark institutions manages FMT according to the European Tissue and Cell directive.
Cultured intestinal bacteria are being studied as an alternative to fecal microbiota transplant. One example is the rectal bacteriotherapy (RBT), developed by Tvede and Helms, containing 12 individually cultured strains of anaerobic and aerobic bacteria originating from healthy human faeces. Research has also been done to identify the most relevant microbes within fecal transplants, which could then be isolated and manufactured via industrial fermentation; such standardized products would be more scalable, would reduce the risk of infections from unwanted microbes, and would improve the scientific study of the approach, since the same substance would be administered each time.
Elephants, hippos, koalas, and pandas are born with sterile intestines, and to digest vegetation need bacteria which they obtain by eating their mothers' feces, a practice termed coprophagia. Other animals eat dung.
In veterinary medicine fecal microbiota transplant has been known as "transfaunation" and is used to treat ruminating animals, like cows and sheep, by feeding rumen contents of a healthy animal to another individual of the same species in order to colonize its gastrointestinal tract with normal bacteria.
Previous terms for the procedure include fecal bacteriotherapy, fecal transfusion, fecal transplant, stool transplant, fecal enema, and human probiotic infusion (HPI). Because the procedure involves the complete restoration of the entire fecal microbiota, not just a single agent or combination of agents, these terms have now been replaced by the new term fecal microbiota transplantation.
- Josiah Zayner, a biohacker who attempted a full fecal microbiota transplant on himself in 2016
- Rowan, Karen (October 20, 2012). "'Poop Transplants' May Combat Bacterial Infections". LiveScience.com. Retrieved October 20, 2012.
- van Nood E, Vrieze A, Nieuwdorp M, Fuentes S, Zoetendal EG, de Vos WM, et al. (January 2013). "Duodenal infusion of donor feces for recurrent Clostridium difficile". The New England Journal of Medicine. 368 (5): 407–15. doi:10.1056/NEJMoa1205037. PMID 23323867. S2CID 25879411.
- Moayyedi P, Yuan Y, Baharith H, Ford AC (August 2017). "Faecal microbiota transplantation for Clostridium difficile-associated diarrhoea: a systematic review of randomised controlled trials". The Medical Journal of Australia. 207 (4): 166–172. doi:10.5694/mja17.00295. PMID 28814204.
- Baunwall, Simon Mark Dahl; Lee, Mads Ming; Eriksen, Marcel Kjærsgaard; Mullish, Benjamin H.; Marchesi, Julian R.; Dahlerup, Jens Frederik; Hvas, Christian Lodberg (November 23, 2020). "Faecal microbiota transplantation for recurrent Clostridioides difficile infection: An updated systematic review and meta-analysis". EClinicalMedicine. 0 (0). doi:10.1016/j.eclinm.2020.100642. ISSN 2589-5370.
- Commissioner, Office of the (March 12, 2020). "Fecal Microbiota for Transplantation: Safety Alert - Risk of Serious Adverse Events Likely Due to Transmission of Pathogenic Organisms". FDA. Retrieved March 21, 2020.
- Brandt LJ, Borody TJ, Campbell J (September 2011). "Endoscopic fecal microbiota transplantation: "first-line" treatment for severe clostridium difficile infection?". Journal of Clinical Gastroenterology. 45 (8): 655–7. doi:10.1097/MCG.0b013e3182257d4f. PMID 21716124.
- Borody TJ, Khoruts A (December 2011). "Fecal microbiota transplantation and emerging applications". Nature Reviews. Gastroenterology & Hepatology. 9 (2): 88–96. doi:10.1038/nrgastro.2011.244. PMID 22183182.
- Borody TJ, Paramsothy S, Agrawal G (August 2013). "Fecal microbiota transplantation: indications, methods, evidence, and future directions". Current Gastroenterology Reports. 15 (8): 337. doi:10.1007/s11894-013-0337-1. PMC 3742951. PMID 23852569.
- Mullish BH, Quraishi MN, Segal JP, McCune VL, Baxter M, Marsden GL, et al. (November 2018). "Clostridium difficile infection and other potential indications: joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines". Gut. 67 (11): 1920–1941. doi:10.1136/gutjnl-2018-316818. PMID 30154172.
- Burke KE, Lamont JT (August 2013). "Fecal transplantation for recurrent Clostridium difficile infection in older adults: a review". Journal of the American Geriatrics Society. 61 (8): 1394–8. doi:10.1111/jgs.12378. PMID 23869970.
- Drekonja D, Reich J, Gezahegn S, Greer N, Shaukat A, MacDonald R, et al. (May 2015). "Fecal Microbiota Transplantation for Clostridium difficile Infection: A Systematic Review". Annals of Internal Medicine. 162 (9): 630–8. doi:10.7326/m14-2693. PMID 25938992.
- Bakken JS, Borody T, Brandt LJ, Brill JV, Demarco DC, Franzos MA, et al. (December 2011). "Treating Clostridium difficile infection with fecal microbiota transplantation". Clinical Gastroenterology and Hepatology. 9 (12): 1044–9. doi:10.1016/j.cgh.2011.08.014. PMC 3223289. PMID 21871249.
- Kelly CR, de Leon L, Jasutkar N (February 2012). "Fecal microbiota transplantation for relapsing Clostridium difficile infection in 26 patients: methodology and results". Journal of Clinical Gastroenterology. 46 (2): 145–9. doi:10.1097/MCG.0b013e318234570b. PMID 22157239.
- Bakken JS (December 2009). "Fecal bacteriotherapy for recurrent Clostridium difficile infection". Anaerobe. 15 (6): 285–9. doi:10.1016/j.anaerobe.2009.09.007. PMID 19778623.
- Floch MH (September 2010). "Fecal bacteriotherapy, fecal transplant, and the microbiome". Journal of Clinical Gastroenterology. 44 (8): 529–30. doi:10.1097/MCG.0b013e3181e1d6e2. PMID 20601895.
- Borody TJ, Campbell J (December 2011). "Fecal microbiota transplantation: current status and future directions". Expert Review of Gastroenterology & Hepatology. 5 (6): 653–5. doi:10.1586/egh.11.71. PMID 22017691.
- Bennet JD, Brinkman M (January 1989). "Treatment of ulcerative colitis by implantation of normal colonic flora". Lancet. 1 (8630): 164. doi:10.1016/S0140-6736(89)91183-5. PMID 2563083.
- Sunkara T, Rawla P, Ofosu A, Gaduputi V (2018). "Fecal microbiota transplant - a new frontier in inflammatory bowel disease". Journal of Inflammation Research. 11: 321–328. doi:10.2147/JIR.S176190. PMC 6124474. PMID 30214266.
- Davar, Diwakar; Dzutsev, Amiran K.; McCulloch, John A.; Rodrigues, Richard R.; Chauvin, Joe-Marc; Morrison, Robert M.; Deblasio, Richelle N.; Menna, Carmine; Ding, Quanquan; Pagliano, Ornella; Zidi, Bochra (February 5, 2021). "Fecal microbiota transplant overcomes resistance to anti–PD-1 therapy in melanoma patients". Science. 371 (6529): 595–602. doi:10.1126/science.abf3363. ISSN 0036-8075.
- Baruch, Erez N.; Youngster, Ilan; Ben-Betzalel, Guy; Ortenberg, Rona; Lahat, Adi; Katz, Lior; Adler, Katerina; Dick-Necula, Daniela; Raskin, Stephen; Bloch, Naamah; Rotin, Daniil (February 5, 2021). "Fecal microbiota transplant promotes response in immunotherapy-refractory melanoma patients". Science. 371 (6529): 602–609. doi:10.1126/science.abb5920. ISSN 0036-8075.
- Baxter M, Colville A (February 2016). "Adverse events in faecal microbiota transplant: a review of the literature". The Journal of Hospital Infection (Submitted manuscript). 92 (2): 117–27. doi:10.1016/j.jhin.2015.10.024. hdl:11287/595264. PMID 26803556.
- Goloshchapov OV, Olekhnovich EI, Sidorenko SV, Moiseev IS, Kucher MA, Fedorov DE, et al. (December 2019). "Long-term impact of fecal transplantation in healthy volunteers". BMC Microbiology. 19 (1): 312. doi:10.1186/s12866-019-1689-y. PMC 6938016. PMID 31888470.
- Commissioner, Office of the (March 24, 2020). "Fecal Microbiota for Transplantation: Safety Alert - Regarding Additional Safety Protections Pertaining to SARS-CoV-2 and COVID-19". FDA. Retrieved March 25, 2020.
- "Fecal Microbiota for Transplantation: Safety Communication- Risk of Serious Adverse Reactions Due to Transmission of Multi-Drug Resistant Organisms". FDA. June 14, 2019. Retrieved June 18, 2019.
- Grady, Denise (June 13, 2019). "Fecal Transplant Is Linked to a Patient's Death, the F.D.A. Warns". The New York Times.
- Cammarota G, Ianiro G, Tilg H, Rajilić-Stojanović M, Kump P, Satokari R, et al. (April 2017). "European consensus conference on faecal microbiota transplantation in clinical practice". Gut. 66 (4): 569–580. doi:10.1136/gutjnl-2016-313017. PMC 5529972. PMID 28087657.
- Mullish BH, Quraishi MN, Segal JP, McCune VL, Baxter M, Marsden GL, et al. (September 2018). "The use of faecal microbiota transplant as treatment for recurrent or refractory Clostridium difficile infection and other potential indications: joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines". The Journal of Hospital Infection. 100 Suppl 1: S1–S31. doi:10.1016/j.jhin.2018.07.037. PMID 30173851.
- Cammarota G, Ianiro G, Tilg H, Rajilić-Stojanović M, Kump P, Satokari R, et al. (April 2017). "European consensus conference on faecal microbiota transplantation in clinical practice". Gut. 66 (4): 569–580. doi:10.1136/gutjnl-2016-313017. PMC 5529972. PMID 28087657.
- Merenstein D, El-Nachef N, Lynch SV (August 2014). "Fecal microbial therapy: promises and pitfalls". Journal of Pediatric Gastroenterology and Nutrition. 59 (2): 157–61. doi:10.1097/mpg.0000000000000415. PMC 4669049. PMID 24796803.
- Woodworth MH, Carpentieri C, Sitchenko KL, Kraft CS (May 2017). "Challenges in fecal donor selection and screening for fecal microbiota transplantation: A review". Gut Microbes. 8 (3): 225–237. doi:10.1080/19490976.2017.1286006. PMC 5479407. PMID 28129018.
- Jørgensen SM, Hansen MM, Erikstrup C, Dahlerup JF, Hvas CL (November 2017). "Faecal microbiota transplantation: establishment of a clinical application framework". European Journal of Gastroenterology & Hepatology. 29 (11): e36–e45. doi:10.1097/meg.0000000000000958. PMID 28863010.
- Terveer EM, van Beurden YH, Goorhuis A, Seegers JF, Bauer MP, van Nood E, et al. (December 2017). "How to: Establish and run a stool bank". Clinical Microbiology and Infection. 23 (12): 924–930. doi:10.1016/j.cmi.2017.05.015. PMID 28529025.
- Khoruts A, Sadowsky MJ (September 2016). "Understanding the mechanisms of faecal microbiota transplantation". Nature Reviews. Gastroenterology & Hepatology. 13 (9): 508–16. doi:10.1038/nrgastro.2016.98. PMC 5909819. PMID 27329806.
- Kelly CR, Kahn S, Kashyap P, Laine L, Rubin D, Atreja A, et al. (July 2015). "Update on Fecal Microbiota Transplantation 2015: Indications, Methodologies, Mechanisms, and Outlook". Gastroenterology. 149 (1): 223–37. doi:10.1053/j.gastro.2015.05.008. PMC 4755303. PMID 25982290.
- Ott SJ, Waetzig GH, Rehman A, Moltzau-Anderson J, Bharti R, Grasis JA, et al. (March 2017). "Efficacy of Sterile Fecal Filtrate Transfer for Treating Patients With Clostridium difficile Infection". Gastroenterology. 152 (4): 799–811.e7. doi:10.1053/j.gastro.2016.11.010. PMID 27866880.
- McDonald JA, Mullish BH, Pechlivanis A, Liu Z, Brignardello J, Kao D, et al. (November 2018). "Inhibiting Growth of Clostridioides difficile by Restoring Valerate, Produced by the Intestinal Microbiota". Gastroenterology. 155 (5): 1495–1507.e15. doi:10.1053/j.gastro.2018.07.014. PMC 6347096. PMID 30025704.
- Zuo T, Wong SH, Lam K, Lui R, Cheung K, Tang W, et al. (April 2018). "Clostridium difficile infection is associated with treatment outcome". Gut. 67 (4): 634–643. doi:10.1136/gutjnl-2017-313952. PMC 5868238. PMID 28539351.
- Draper LA, Ryan FJ, Smith MK, Jalanka J, Mattila E, Arkkila PA, et al. (December 2018). "Long-term colonisation with donor bacteriophages following successful faecal microbial transplantation". Microbiome. 6 (1): 220. doi:10.1186/s40168-018-0598-x. PMC 6288847. PMID 30526683.
- Zhang YJ, Li S, Gan RY, Zhou T, Xu DP, Li HB (April 2015). "Impacts of gut bacteria on human health and diseases". International Journal of Molecular Sciences. 16 (4): 7493–519. doi:10.3390/ijms16047493. PMC 4425030. PMID 25849657.
- Paramsothy S, Nielsen S, Kamm MA, Deshpande NP, Faith JJ, Clemente JC, et al. (April 2019). "Specific Bacteria and Metabolites Associated With Response to Fecal Microbiota Transplantation in Patients With Ulcerative Colitis". Gastroenterology. 156 (5): 1440–1454.e2. doi:10.1053/j.gastro.2018.12.001. PMID 30529583.
- Gerke H (December 2014). "Whats the lowdown on 'fecal transplantation'?". Health at Iowa. U of Iowa. Retrieved January 14, 2015.
- "Therapeutic Poop: Hope for Cure of Childhood Diarrhea Comes Straight from the Gut". The Johns Hopkins Children's Center. The Johns Hopkins University. July 29, 2013.
- Lewin RA (2001). "More on Merde". Perspectives in Biology and Medicine. 44 (4): 594–607. doi:10.1353/pbm.2001.0067. PMID 11600805.
- Eiseman B, Silen W, Bascom GS, Kauvar AJ (November 1958). "Fecal enema as an adjunct in the treatment of pseudomembranous enterocolitis". Surgery. 44 (5): 854–9. PMID 13592638.
- Borody TJ, George L, Andrews P, Brandl S, Noonan S, Cole P, et al. (May 1989). "Bowel-flora alteration: a potential cure for inflammatory bowel disease and irritable bowel syndrome?". The Medical Journal of Australia. 150 (10): 604. doi:10.5694/j.1326-5377.1989.tb136704.x. PMID 2783214.
- "FDA struggles to regulate fecal transplants". CBS News. Associated Press. June 26, 2014.
- "Public Workshop: Fecal Microbiota for Transplantation". Food and Drug Administration. March 10, 2014.
- 78 FR 12763, February 25, 2013
- Smith MB, Kelly C, Alm EJ (February 19, 2014). "Policy: How to regulate faecal transplants". Nature.
- AGA Confirms IND is Required for Fecal Microbiota Transplantation, American Gastroenterological Association, May 6, 2013, archived from the original on May 10, 2013
- "Guidance for Industry: Enforcement Policy Regarding Investigational New Drug Requirements for Use of Fecal Microbiota for Transplantation to Treat Clostridium difficile Infection Not Responsive to Standard Therapies". Food and Drug Administration. July 2013.
- "Draft Guidance for Industry: Enforcement Policy Regarding Investigational New Drug Requirements for Use of Fecal Microbiota for Transplantation to Treat Clostridium difficile Infection Not Responsive to Standard Therapies". Food and Drug Administration. March 2014.
- Emanuel G (March 7, 2014). "MIT Lab Hosts Nation's First Stool Bank, But Will It Survive?". WBUR-FM.
- Ratner M (May 2014). "Fecal transplantation poses dilemma for FDA". Nature Biotechnology. 32 (5): 401–2. doi:10.1038/nbt0514-401. PMID 24811495.
- "Important Safety Alert Regarding Use of Fecal Microbiota for Transplantation and Risk of Serious Adverse Reactions Due to Transmission of Multi-Drug Resistant Organisms". FDA. December 20, 2019.
- https://www.fda.gov/vaccines-blood-biologics/safety-availability-biologics/safety-alert-regarding-use-fecal-microbiota-transplantation-and-risk-serious-adverse-events-likely. Missing or empty
- "Safety Alert Regarding Use of Fecal Microbiota for Transplantation and Additional Safety Protections Pertaining to SARS-CoV-2 and COVID-19". FDA. April 9, 2020.
- Smith, Peter Andrey (February 17, 2014). "A New Kind of Transplant Bank". The New York Times. Retrieved July 10, 2014.
- Dupont HL (October 2013). "Diagnosis and management of Clostridium difficile infection". Clinical Gastroenterology and Hepatology. 11 (10): 1216–23, quiz e73. doi:10.1016/j.cgh.2013.03.016. PMID 23542332.
- Tvede M, Tinggaard M, Helms M (January 2015). "Rectal bacteriotherapy for recurrent Clostridium difficile-associated diarrhoea: results from a case series of 55 patients in Denmark 2000-2012". Clinical Microbiology and Infection. 21 (1): 48–53. doi:10.1016/j.cmi.2014.07.003. PMID 25636927.
- Allen-Vercoe E; Petrof EO (May 1, 2013). "Artificial stool transplantation: progress towards a safer, more effective and acceptable alternative". Expert Review of Gastroenterology & Hepatology. 7 (4): 291–293. doi:10.1586/EGH.13.16. ISSN 1747-4124. PMID 23639085. Wikidata Q60174470.
- "BBC Nature – Dung eater videos, news and facts". Bbc.co.uk. n.d. Retrieved November 27, 2011.
- DePeters EJ, George LW (December 2014). "Rumen transfaunation". Immunology Letters. 162 (2 Pt A): 69–76. doi:10.1016/j.imlet.2014.05.009. PMID 25262872.
|Wikispecies has information related to Microbiota.|