INTRODUCTION — Fecal microbiota transplantation (FMT) refers to instillation of processed stool collected from a healthy donor into the intestinal tract of a patient with Clostridioides difficile infection (CDI) [1-4]. FMT protocols vary between institutions, and comparative efficacy studies are few and underpowered.
Available data are strongest for use of FMT in the setting of recurrent CDI; recurrent CDI is defined by complete abatement of CDI symptoms while on appropriate therapy, followed by reappearance of symptoms within two to eight weeks after treatment has been stopped [2]. Recurrent CDI occurs in 10 to 25 percent of patients treated with antimicrobial therapy.
Data on additional circumstances in which FMT may be beneficial, such as severe and fulminant infection, are limited.
Issues related to FMT are reviewed here. Other issues related to CDI are discussed separately. (See "Clostridioides difficile infection in adults: Epidemiology, microbiology, and pathophysiology" and "Clostridioides difficile infection in adults: Clinical manifestations and diagnosis" and "Clostridioides difficile infection in adults: Treatment and prevention".) (Related Pathway(s): Clostridioides difficile infection: Treatment of adults with an initial or recurrent infection.)
RATIONALE — The gastrointestinal tract harbors a highly complex community of microorganisms that exist in symbiosis with the host. The human gut microbiota is estimated to consist of at least 1014 bacteria and as many as 1000 to 1200 bacterial species, most of which reside in the colon [5].
The beneficial roles mediated by the microbiota for the host include vitamin synthesis, fermentation of dietary carbohydrates, metabolism of bile and host hormones, and competitive exclusion ("colonization resistance") of pathogens taking residence in the gut community [6]. The microbiota also influences the development and maturation of the immune system through interactions with the gut epithelium [7,8].
Administration of antibiotics can significantly alter the composition of the microbiota, which can lead to selective removal of bacteria that serve as a barrier to pathogen colonization and/or persistence [9,10]. Antibiotic-mediated changes in the composition of the gut microbiota may also lead to homeostatic imbalance through alterations in the gut barrier functions and result in mucosal immune defects, which would predispose the host to enteric infections such as C. difficile by allowing environmentally acquired spores to germinate and successfully colonize the gut [11].
Recurrence of CDI is an increasing problem following antimicrobial therapy. Patients with recurrent CDI have been observed to have reduced diversity of the intestinal microbiome and diminished numbers of bacteria relative to healthy individuals [12,13]. Transplantation of stool microbiota from healthy individuals to patients with recurrent C. difficile can restore these missing strains and break the cycle of CDI recurrence [14-17].
SAFETY AND EFFICACY
Cure rates — The efficacy of FMT is discussed separately. (See "Clostridioides difficile infection in adults: Treatment and prevention".)
More than one administration of FMT may be necessary for optimal efficacy, and this is the reason we suggest at least two sequential administrations of FMT, as discussed below (see 'Administration protocol' below). In one randomized trial including 232 patients with recurrent CDI treated with fresh or frozen FMT administered via enema, patients with no improvement in symptoms by day 4 received an additional FMT between days 5 and 9; those who did not respond to two FMTs were offered repeat FMT or antibiotic therapy [18]. The efficacy for one FMT was approximately 50 percent and increased to 75 percent for two FMT administrations and approximately 90 percent for more than two FMT administrations. However, despite this, the US Food and Drug Administration (FDA) generally recommends only a single administration.
Alteration of the colonic microbiota following FMT appears to be durable [15,19,20]. In one retrospective study including 374 patients with risk factor exposure, 78 percent (95% CI 73-84) had durable response to FMT at one year [20]. Similarly, in an observational study including 137 patients who underwent FMT for recurrent CDI, durable cure at median 22 months follow-up was observed in 82 percent of patients; patients with recurrence had antibiotic exposure following FMT [19].
The efficacy of FMT in patients with underlying inflammatory bowel disease (IBD) is lower than in patients without IBD, and flares of underlying disease activity have been reported following FMT for recurrent CDI in patients with IBD [21-23]. The FMT efficacy rates differ by route of delivery. (See 'Choice of delivery route' below.)
Other effects — CDI has been associated with bloodstream infection (BSI). FMT may decrease the strength of that association. In a prospective cohort study of 290 patients with recurrent CDI, treatment with FMT was associated with a lower risk of subsequent BSI within 90 days compared with antibiotic therapy for CDI [24]. The FMT group also had fewer days of hospitalization and an increase in overall survival compared to the antibiotic group.
Adverse events and complications — In patients without underlying comorbidities, FMT is generally well-tolerated; mild to moderate adverse events (such as abdominal discomfort) are generally self-limited [19,25-30]. In one review including more than 1000 patients, the incidence of serious adverse events including death, infection, and relapse of inflammatory bowel disease was 3.5, 2.5, and 0.6 percent, respectively [27].
Potential risks include:
●Procedural complications - Complications associated with the FMT procedure (upper gastrointestinal bleeding after nasogastric tube insertion, colon perforation during colonoscopy) have occurred; the frequency of such complications is likely similar to the frequency of complications when these procedures are performed for other indications [31]. (See 'Choice of delivery route' below and "Overview of colonoscopy in adults", section on 'Complications' and "Inpatient placement and management of nasogastric and nasoenteric tubes in adults", section on 'Complications'.)
●Risk for transmission of infection - FMT is associated with risk for transmission of infectious agents:
•In a surveillance report including more than 10,000 fecal microbiota preparations, adverse events occurred in 7 patients who received FMT from a stool donor who was colonized with Shiga toxin–producing Escherichia coli; the organism went undetected despite screening [32].
•In 2019, the FDA released a safety alert highlighting two cases (one fatal) of invasive infection due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli among FMT recipients [33,34]. One patient had profound neutropenia as a result of hematopoietic cell transplantation. No ESBL E. coli-related illness occurred in 16 other individuals who received the same contaminated capsules.
•Cases of norovirus gastroenteritis have been attributed to FMT, despite use of asymptomatic donors with no known sick contacts [35].
Strategies to reduce transmission risk include careful selection of FMT candidates and adherence to guidelines for donor selection. (See 'Candidates for FMT' below and 'Stool donor selection' below.)
CLINICAL APPROACH
Candidates for FMT — For patients who have received appropriate antibiotic treatment for at least three CDI episodes (ie, initial episode plus two recurrences), who subsequently present with a fourth or further episode (third or subsequent recurrence), we favor FMT in regions where available [1,2]. However, some favor FMT for patients who have received antibiotic treatment for at least two CDI episodes (ie, initial episode plus one recurrence) [3]. (See "Clostridioides difficile infection in adults: Treatment and prevention".)
We avoid FMT in immunocompromised patients and patients with inflammatory bowel disease.
FMT may have a role in management of patients with severe or fulminant disease; this requires further study. (See "Clostridioides difficile infection in adults: Treatment and prevention", section on 'Fulminant colitis' and "Clostridioides difficile infection in adults: Treatment and prevention".)
Pretreatment evaluation
History and physical examination — The aim of the history is to guide selection of the route of delivery in patients who are candidates for FMT. (See 'Our approach' below.)
Patients should be evaluated to determine if they have a history of dysphagia or conditions that could prevent passage of FMT capsules or cause capsules to break open prematurely. Conditions that would preclude oral administration of FMT capsules include a known esophageal stricture, Zenker's diverticulum, gastroparesis, or a prior history of small bowel obstruction.
The history should also include prior surgeries including subtotal colectomy or colostomy, as FMT administration via colonoscopy may be associated with diminished efficacy due to reduced colonic mucosa area.
In addition, FMT recipients require assessment of their sedation needs and risks associated with endoscopy. (See "Overview of colonoscopy in adults", section on 'Sedation assessment'.)
Laboratory testing — There are no standard guidelines regarding the approach to recipient laboratory testing prior to FMT. We perform baseline serologic testing for viral hepatitis (A, B, and C), HIV, and syphilis; in addition, we perform stool culture for enteric pathogens and stool microscopy examination for ova and parasites, and we screen stool for multidrug-resistant organisms. Such screening is important to document presence of infection prior to FMT administration (which could serve as a potential source of disease transmission).
Some clinicians favor expanded laboratory testing for donor stool to include severe acute respiratory syndrome coronavirus 2 and drug-resistant bacteria [28,36]. However, the cost of expanded stool screening may limit FMT access [37].
Choice of delivery route
Delivery routes and efficacy — FMT may be administered via oral capsules, lower gastrointestinal (GI) tract procedure (colonoscopy, retention enema), or upper GI tract procedure (nasojejunal [NJ]/nasoduodenal [ND] tube) [38,39]. The choice is based in part on clinical circumstances, available options, and patient preference. There have been few trials comparing the effectiveness of different modalities; in one meta-analysis including 37 studies (of which 7 were randomized trials) and more than 51,000 patients, the mean response for FMT in recurrent CDI was 92 percent; lower administration was more effective than upper administration (92 to 97 percent versus 82 to 94 percent) [40].
●Oral capsules – Administration of FMT via oral capsules is convenient and noninvasive [41,42]. In a meta-analysis that included 15 studies (most of which were observational) and more than 700 patients, 82 percent of patients treated with oral capsule-based FMT did not have recurrence during follow-up, which is similar to efficacy rates seen with colonoscopy-based FMT [43]. As an example of one of the randomized trials included in the meta-analysis, among 116 patients with recurrent CDI randomized to FMT administered via oral capsule or colonoscopy, cure rates for prevention of recurrent CDI were 96 percent in both groups at 12 weeks [44]. Rates of minor adverse events in the oral capsule and colonoscopy groups were 5 and 13 percent, respectively. Larger studies are needed to confirm these results and evaluate long-term effectiveness and safety.
●Colonoscopy – Administration of FMT via colonoscopy allows delivery of donor stool to the cecum and distal small bowel. In addition, it permits inspection of the colon for presence of colitis, pseudomembranes, polyps, or cancer. However, colonoscopy carries some procedural risk and increases health care utilization and costs. Several studies have noted success with administration of FMT via colonoscopy [17,26,45,46]. Cure rates after lower GI tract administration are somewhat higher than cure rates after upper GI tract administration. In one retrospective study including 22 patients with recurrent CDI, patients treated with lower GI FMT recovered faster than patients treated with upper GI FMT (1.6 versus 2.4 days) and were more likely to achieve cure (100 versus 75 percent) [47,48].
●Retention enema – Administration of donor stool via retention enema allows delivery of donor stool up to the splenic flexure. Retention enema is inexpensive and has low procedural risk. Self-administered home FMT via enema kit has also been performed successfully [49]. However, it may be difficult for some patients to retain the donor material and may therefore require multiple treatments.
While several studies have noted success with this approach, cure rates with enema appear to be lower than colonoscopy [49-53].
●Nasojejunal/nasoduodenal tube – Administration of FMT via NJ/ND tube allows delivery of donor stool to the small bowel and then throughout the colon [25,54-59]. Placement of NJ/ND tube is uncomfortable and requires radiologic confirmation of tube placement. Administration via the upper GI tract also carries some risk of vomiting and aspiration.
In a randomized clinical trial evaluating FMT, 43 patients with recurrent CDI were randomized to receive treatment with oral vancomycin (500 mg orally four times per day for 14 days), oral vancomycin with bowel lavage, or a four-day course of vancomycin followed by bowel lavage and subsequent FMT administered via ND tube [25]. Cure rates were higher among those who received FMT than those who did not (81 versus 27 and 31 percent, respectively).
Cure rates after upper tract administration are somewhat lower than cure rates after lower tract administration [47,48]. Single FMT instillations via the upper GI tract have lower rates of success than via the lower GI tract, but success rates generally increase with repeated instillations [18,25,60,61].
Our approach — The choice of FMT delivery route depends in part on patient preferences, individual risk, availability of resources and expertise, and cost. (See 'History and physical examination' above.)
The American College of Gastroenterology 2021 guidelines favor administration of FMT via colonoscopy or oral capsules, with delivery by enema if other methods are unavailable [3]. If feasible, we administer FMT via oral capsules; in some areas, stool banks serve as a source of capsules prepared from screened donors [62]. If FMT administration via oral capsules is not feasible, we administer FMT via colonoscopy, followed by retention enema the following day. If FMT administration via oral capsule, colonoscopy, or retention enema is not feasible, we administer FMT via an endoscopically placed NJ (preferably) or ND tube.
In patients with history of subtotal colectomy or colostomy, transcolonic administration is more likely to fail. Administration via oral capsules or upper GI tract is preferred. If FMT administration via colonoscopy is pursued in such patients, we administer daily retention enemas for five days. (See 'Pretreatment evaluation' above.)
In patients with severe colitis or toxic megacolon, FMT administration via colonoscopy may not be feasible. In such patients, FMT is administered via NJ tube or by a gently performed rectal enema. For patients with severe CDI who would otherwise require colectomy, a promising alternative approach consists of loop colostomy followed by antegrade administration of FMT; further study is needed [63].
Administration protocol
Oral capsules — Stool banks serve as a source of capsules prepared from screened donors in some areas [62]. A large number of capsules (as many as 40) may be required [44]. Patients undergoing FMT via oral capsules should be managed according to the protocol of the capsule manufacturer.
Lower GI tract — There is no consensus on the optimal protocol for FMT administration via the lower GI tract; the following discussion reflects the clinical approach of the authors.
●For patients with active colitis, we administer oral vancomycin (500 mg orally twice daily) for seven days prior to FMT; the last dose should be 24 hours before the procedure. In the absence of active colitis, we do not administer antibiotics prior to FMT, given some data suggesting this practice may be associated with diminished efficacy [64-67].
●The day prior to the procedure, administer three to four liters of oral polyethylene glycol with electrolytes purgative. This lavage may reduce the density of vegetative C. difficile organisms, including the metabolically inactive spores that could otherwise convert to vegetative forms. We forego the lavage in patients too ill to tolerate it. (See "Bowel preparation before colonoscopy in adults", section on 'Polyethylene glycol-electrolyte lavage solution'.)
●Patients should be kept fasting overnight. The day of the procedure, administer 200 to 300 g of donor stool suspended in 200 to 300 mL of sterile normal saline via colonoscopy into the cecum or terminal ileum, within 10 minutes of preparation. Colonoscopy must be performed with caution given increased risk of perforation in the setting of CDI. If feasible, the scope should be passed to the cecum to exclude other pathology. If this is unfeasible due to colonic inflammation, the infusion should be performed at the most proximal aspect of the colon reachable via colonoscopy.
●Patients may resume a regular diet and medications two hours after the colonoscopy is complete.
●The following day, FMT is administered via a retention enema (200 to 300 g of donor stool suspended in 200 to 300 mL of sterile normal saline). The enema should be retained for at least six hours if feasible. We pretreat with loperamide (2 mg, followed by an additional 2 mg every two hours, up to a total of 8 mg) to increase enema retention. Patients should be advised to retain the stool as long as possible.
●In patients with CDI in the setting of inflammatory bowel disease or a history of a subtotal colectomy or colostomy, we administer daily retention enemas of stool for five days.
In our clinical experience, the outlined protocol for FMT administration via the lower GI tract has been effective in achieving prolonged cure in over 90 percent of patients after a single procedure (>98 percent after two procedures), with long-term resolution of symptoms (diarrhea, abdominal pain or cramping) [48,60,68]. Efficacy rates for FMT administration via the lower GI tract are discussed separately. (See 'Choice of delivery route' above.)
Upper GI tract — One protocol for upper GI tract FMT administration consists of the following steps:
●For patients with active colitis, we administer oral vancomycin (500 mg orally twice daily) for seven days prior to FMT; the last dose should be 24 hours before the procedure. In the absence of active colitis, we do not administer antibiotics prior to FMT, given some data suggesting this practice may be associated with diminished efficacy [64-67].
●Patients should be kept fasting overnight. The day prior to the procedure, some experts administer three to four liters of oral polyethylene glycol with electrolytes purgative; this lavage may reduce the density of vegetative C. difficile organisms, including the metabolically inactive spores that could otherwise convert to vegetative forms. However, it is reasonable to forgo the lavage in patients too ill to tolerate it. (See "Bowel preparation before colonoscopy in adults", section on 'Polyethylene glycol-electrolyte lavage solution'.)
●The evening prior to the procedure and the day of the procedure, administer a proton pump inhibitor (eg, omeprazole 20 mg). The rationale is to reduce the gastric acid barrier and enhance successful passage of live bacteria through the gastric mucosa.
●The day of the procedure, place a NJ (preferred) or ND tube through the nostril and advance into the small bowel. Tube position is confirmed by radiograph and gastrografin follow-through. Use of sedation with ND instillation minimally increases the potential risk of aspiration; we forgo sedation if feasible [69].
●We administer metoclopramide (10 mg intravenously), approximately 15 to 30 minutes prior to instillation of stool. Diluted stool (25 to 30 g of stool diluted in 50 mL of saline) is subsequently administered slowly, over 5 to 10 minutes, via NJ or ND tube.
●Patients may benefit from repeat FMT administered daily over multiple days, given the lower efficacy of single administration via the upper GI tract as compared with colonoscopy. The total number is based on the response to treatment. (See 'Delivery routes and efficacy' above.)
Monitoring and disposition — FMT administered via oral capsules, ND/NJ tube, or retention enema can be performed in the outpatient setting. Following colonoscopy, hospitalization is not routinely recommended. However, some patients may require hospital admission; this decision should be tailored to individual patient circumstances.
Patients with nonsevere CDI treated with FMT typically have resolution of abdominal discomfort and diarrhea in 36 to 48 hours [18,25,29,48,59,70,71]. In one survey including 137 patients treated with FMT for recurrent CDI, durable response (no recurrence of CDI at 22 months of follow-up) was observed in 82 percent of patients [19].
FMT PREPARATION
Stool donor selection — Stool donors must be rigorously screened through questionnaires as well as blood and stool testing. Donors must be healthy and have a daily formed bowel movement. Exclusion criteria are summarized in the table (table 1) [28].
Careful evaluation of candidate stool donors for occult pathogens is important to minimize the risk of infection and to maximize the likelihood for a successful treatment outcome.
If feasible, FMT should be performed with stool screened by a stool bank. If prescreened donor stool is not available, our approach to screening includes the following tests:
●Serologic testing for viral hepatitis (A, B, and C), HIV, and syphilis
●Stool tests should include:
•Giardia antigen, Cryptosporidium antigen
•Microscopy examination for ova and parasites and acid-fast stain microscopy (for Cyclospora, Isospora, Dientamoeba fragilis, and Blastocystis hominis)
•Molecular tests for norovirus and rotavirus
•Bacterial culture for detection of enteric bacterial pathogens, as well as testing for multidrug-resistant enteric organisms
•Nucleic acid amplification tests for enteropathogenic E. coli and Shigatoxin-producing E. coli [72]
•C. difficile to rule out asymptomatic carriage, even if stool is formed
•Helicobacter pylori stool antigen assay (for FMT to be administered via upper gastrointestinal [GI] tract)
•Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; for stool donated after December 1, 2019) [73]. In March 2020, the US Food and Drug Administration (FDA) advised that for stool donated after December 1, 2019, the donor and the samples should be screened for SARS-CoV-2 (the virus that causes coronavirus disease 2019), since this virus can be detected in stool and thus theoretically could transmit virus [73,74].
The clinical use of FMT has the potential to transmit monkeypox virus. On August 22, 2022, the FDA issued guidance to reduce the risk of transmission of monkeypox virus [75]. Measures recommended by the FDA include screening donors, with questions directed at identifying those at high risk for monkeypox and those with recent or active monkeypox virus infection, and the development of exclusion criteria to exclude donors with a positive questionnaire screen. Donor screening should be performed retrospectively on FMT prepared from donor stool collected on or after March 15, 2022. The FDA also recommends that all FMT recipients undergo informed consent regarding the possible risk of transmitting monkeypox virus via FMT. This recommendation is based on the presence of monkeypox virus DNA in rectal swabs and/or stool samples from infected individuals, including those without symptoms of monkeypox disease [76]. (See "Epidemiology, clinical manifestations, and diagnosis of mpox (monkeypox)", section on 'Transmission'.)
FMT products
Stool-based products — In general, FMT protocols utilize donor stool suspended in normal saline prior to administration (via colonoscopy, enema, or nasoduodenal/nasojejunal tube). Stool is homogenized (using blender, manual effort, or other method) to liquid consistency and filtered (eg, gauze, coffee filter, strainer) to remove particulate matter. This processed specimen is then either directly infused into the GI tract or further centrifuged and capsulized in gelatin capsules that can be administered orally. (See 'Choice of delivery route' above and 'Oral capsules' above.)
Stool banks serve as a source of capsules prepared from screened donors in some areas [62].
Use of frozen stool preparations for FMT has been shown to be noninferior to fresh stool preparations and allows the use of stool banks for distribution of FMT [18,77]. In one randomized trial including 219 patients with recurrent CDI randomized to receive frozen or fresh FMT via rectal enema, the rates of clinical resolution were comparable (75 versus 70 percent) [18].
Specific bacterial FMT — Specific bacterial stool substitutes for FMT are under investigation for the treatment and prevention of recurrence of CDI [78,79]. In a phase III trial, 182 patients with recurrent (three or more episodes) CDI who had resolution of symptoms after treatment with standard-of-care antibiotics were assigned an oral capsule composed of live purified Firmicutes spores (SER-109) or placebo. Administration of SER-109 significantly decreased recurrence rates relative to placebo (21 versus 47 percent) up to 24 weeks after treatment [78,80].
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Clostridioides difficile infection".)
INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topic (see "Patient education: C. difficile infection (The Basics)")
●Beyond the Basics topic (see "Patient education: Antibiotic-associated diarrhea caused by Clostridioides difficile (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Fecal microbiota transplantation (FMT; instillation of processed stool collected from a healthy donor into the intestinal tract of a patient with recurrent Clostridioides difficile infection [CDI]) is effective for treatment of recurrent CDI. FMT is a relatively new therapy; protocols vary between institutions, and comparative efficacy studies are few and underpowered. (See 'Introduction' above.)
●Patients with recurrent CDI have been observed to have reduced diversity of the intestinal microbiome and diminished numbers of bacteria relative to healthy individuals. Transplantation of stool microbiota from healthy individuals to patients with recurrent C. difficile can restore these missing strains and break the cycle of CDI recurrence. (See 'Rationale' above.)
●For patients who have received appropriate antibiotic treatment for at least three CDI episodes (ie, initial episode plus two recurrences), who subsequently present with a fourth or further episode (third or subsequent recurrence), we suggest FMT in settings where expertise is available (Grade 2B). (See 'Cure rates' above and "Clostridioides difficile infection in adults: Treatment and prevention".)
●FMT may be administered via oral capsules, lower gastrointestinal (GI) tract procedure (colonoscopy, retention enema), or upper GI tract procedure (nasojejunal [NJ]/nasoduodenal [ND] tube). The optimal approach to FMT administration is uncertain. The pretreatment evaluation can guide selection of the route of delivery in patients who are candidates for FMT. (See 'Pretreatment evaluation' above and 'Choice of delivery route' above.)
●The choice of delivery route depends in part on patient preferences, individual risk, availability of resources and expertise, and cost. If feasible, we administer FMT via oral capsules. If FMT administration via oral capsules is not feasible, we administer FMT via colonoscopy followed by a retention enema the following day. We reserve FMT administration via NJ or ND tube for patients who cannot undergo FMT via an alternate route. (See 'Our approach' above.)
●Patients with nonsevere CDI treated with FMT typically have resolution of abdominal discomfort and diarrhea in 36 to 48 hours. (See 'Monitoring and disposition' above.)
●Rigorous screening of candidate stool donors for occult pathogens is important to minimize the risk of infection. Stool donors must be healthy and have a daily bowel movement. Exclusion criteria are summarized in the table (table 1). (See 'Stool donor selection' above.)
●Stool is homogenized to liquid consistency and filtered to remove particulate matter. This specimen is then infused into the GI tract or further centrifuged and capsulized in gelatin capsules that can be administered orally. (See 'FMT products' above.)
ACKNOWLEDGMENTS — The UpToDate editorial staff acknowledges Sharyn Leis, RN, Gerald Pang, PhD, and Antony Wettstein, MBBS (Hons), who contributed to an earlier version of this topic review.
We are saddened by the death of Paul Rutgeerts, MD, who passed away in September 2020. UpToDate gratefully acknowledges Dr. Rutgeerts' work as our Section Editor for Gastroenterology.