Success of self-administered home fecal transplantation for chronic Clostridium difficile infection

The Microbiome Modulates the Immune System to Influence Cancer Therapy

The gut microbiota composition can affect the tumor microenvironment and its interaction with the immune system, thereby having implications for treatment predictions. This article reviews the studies available to better understand how the gut microbiome helps the immune system fight cancer. To describe this fact, different mechanisms and approaches utilizing probiotics to improve advancements in cancer treatment will be discussed. Moreover, not only calorie intake but also the variety and quality of diet can influence cancer patients' immunotherapy treatment because dietary patterns can impair immunological activities either by stimulating or suppressing innate and adaptive immunity. Therefore, it is interesting and critical to understand gut microbiome composition as a biomarker to predict cancer immunotherapy outcomes and responses. Here, more emphasis will be given to the recent development in immunotherapies utilizing microbiota to improve cancer therapies, which is beneficial for cancer patients.

Is there a role for microbiome-based approach in common variable immunodeficiency?

Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by low levels of serum immunoglobulins and increased susceptibility to infections, autoimmune disorders and cancer. CVID embraces a plethora of heterogeneous manifestations linked to complex immune dysregulation. While CVID is thought to be due to genetic defects, the exact cause of this immune disorder is unknown in the large majority of cases. Compelling evidences support a linkage between the gut microbiome and the CVID pathogenesis, therefore a potential for microbiome-based treatments to be a therapeutic pathway for this disorder. Here we discuss the potential of treating CVID patients by developing a gut microbiome-based personalized approach, including diet, prebiotics, probiotics, postbiotics and fecal microbiota transplantation. We also highlight the need for a better understanding of microbiota-host interactions in CVID patients to prime the development of improved preventive strategies and specific therapeutic targets.

Fecal Microbiota Transfer for Clostridium difficile Infection and Its Effects on Recurrent Urinary Tract Infection

IMPORTANCE

Recurrent urinary tract infection (rUTI) poses a significant management challenge, and fecal microbiota transfer (FMT) has been shown in a limited manner to positively effect rUTI.

OBJECTIVES

The objective of this study was to compare UTI rates after FMT for Clostridium difficile infection (CDI) in patients with previously diagnosed rUTI and patients without a previous diagnosis of rUTI.

STUDY DESIGN

This was a retrospective cohort study of female patients who underwent FMT between 2015 and 2020 and were identified from a database at a tertiary care referral center. The electronic medical record was queried for demographic and UTI characteristics in the 3 years before and 5 years after FMT, which were compared between patients with or without a preexisting history of rUTI.

RESULTS

One hundred thirty-five patients were included, 17 of whom had a preexisting history of rUTI. The median number of culture-proven UTIs was 1 in the rUTI group versus 0 in the non-rUTI group both in the 1 year ( P = 0.003) and 3 years ( P < 0.001) before FMT. Most UTIs before and after FMT were Escherichia coli UTIs (53.8%) and carried some antibiotic resistance (54.6%). Comparatively, in the year after FMT, there were no differences between groups in UTI frequency or antibiotic administration (0 [0-1] vs 0.5 [0-1], P = 0.28). A trend toward decreased frequency of UTI in the 1 year after FMT was seen in the rUTI group. On survival analysis, there was a nonsignificant decrease in the 3-year UTI-free rate for the rUTI group compared with the non-rUTI group (76.5% vs 90.1%, P = 0.07).

CONCLUSIONS

Patients with recurrent UTI undergoing FMT for recurrent CDI experienced a trend toward a decrease in frequency of UTI after FMT.

Microbiome Contributions to Health

The human microbiome is vast and is present in spaces previously thought to be sterile such as the lungs. A healthy microbiome is diverse and functions in an adaptive way to support local as well as organism health and function. Furthermore, a normal microbiome is essential for normal immune system development rendering the array of microbes that live in and on the human body key components of homeostasis. A wide array of clinical conditions and interventions including anesthesia, analgesia, and surgical intervention may derange the human microbiome in a maladaptive fashion with bacterial responses spanning decreased diversity to transformation to a pathogenic phenotype. Herein, we explore the normal microbiome of the skin, gastrointestinal tract, and the lungs as prototype sites to describe the influence of the microbiomes in each of those locations on health, and how care may derange those relations.

Mycobiome and Inflammatory Bowel Disease: Role in Disease Pathogenesis, Current Approaches and Novel Nutritional-based Therapies

Inflammatory bowel disease (IBD), a disorder characterized by chronic inflammation of the gastrointestinal (GI) tract and a range of adverse health effects including diarrhea, abdominal pain, vomiting, and bloody stools, affects nearly 3.1 million genetically susceptible adults in the United States today. Although the etiology of IBD remains unclear, genetics, stress, diet, and gut microbiota dysbiosis- especially in immunocompromised individuals- have been identified as possible causes of disease. Although previous research has largely focused on the role of bacteria in IBD pathogenesis, recently observed alterations of fungal load and biodiversity in the GI tract of afflicted individuals suggest interkingdom interactions amongst different gut microbial communities, particularly between bacteria and fungi. These discoveries point to the potential utilization of treatment approaches such as antibiotics, antifungals, probiotics, and postbiotics that target both bacteria and fungi in managing IBD. In this review, we discuss the impact of specific fungi on disease pathogenesis, with a focus on the highly virulent genus Candida and how the presence of certain co-enzymes impacts its virulence. In addition, we evaluate current gut microbiome-based therapeutic approaches with the intention of better understanding the mechanisms behind novel therapies.

The Use of Gut Microbial Modulation Strategies as Interventional Strategies for Ageing

Gut microbial composition codevelops with the host from birth and is influenced by several factors, including drug use, radiation, psychological stress, dietary changes and physical stress. Importantly, gut microbial dysbiosis has been clearly associated with several diseases, including cancer, rheumatoid arthritis and Clostridium difficile-associated diarrhoea, and is known to affect human health and performance. Herein, we discuss that a shift in the gut microbiota with age and reversal of age-related modulation of the gut microbiota could be a major contributor to the incidence of numerous age-related diseases or overall human performance. In addition, it is suggested that the gut microbiome of long-lived animals such as reptiles should be investigated for their unique properties and contribution to the potent defense system of these species could be extrapolated for the benefit of human health. A range of techniques can be used to modulate the gut microbiota to have higher abundance of “beneficial” microbes that have been linked with health and longevity.

Exploring the multifactorial aspects of Gut Microbiome in Parkinson's Disease

Advanced research in health science has broadened our view in approaching and understanding the pathophysiology of diseases and has also revolutionised diagnosis and treatment. Ever since the establishment of Braak’s hypothesis in the propagation of alpha-synuclein from the distant olfactory and enteric nervous system towards the brain in Parkinson’s Disease (PD), studies have explored and revealed the involvement of altered gut microbiota in PD. This review recapitulates the gut microbiome associated with PD severity, duration, motor and non-motor symptoms, and antiparkinsonian treatment from recent literature. Gut microbial signatures in PD are potential predictors of the disease and are speculated to be used in early diagnosis and treatment. In brief, the review also emphasises on implications of the prebiotic, probiotic, faecal microbiota transplantation, and dietary interventions as alternative treatments in modulating the disease symptoms in PD.

Holistic Approach to Immune Checkpoint Inhibitor-Related Adverse Events

Immune checkpoint inhibitors (ICIs) block inhibitory molecules, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), or its ligand, programmed cell death protein ligand 1 (PD-L1) and enhance antitumor T-cell activity. ICIs provide clinical benefits in a percentage of patients with advanced cancers, but they are usually associated with a remarkable spectrum of immune-related adverse events (irAEs) (e.g., rash, colitis, hepatitis, pneumonitis, endocrine, cardiac and musculoskeletal dysfunctions). Particularly patients on combination therapy (e.g., anti-CTLA-4 plus anti-PD-1/PD-L1) experience some form of irAEs. Different mechanisms have been postulated to explain these adverse events. Host factors such as genotype, gut microbiome and pre-existing autoimmune disorders may affect the risk of adverse events. Fatal ICI-related irAEs are due to myocarditis, colitis or pneumonitis. irAEs usually occur within the first months after ICI initiation but can develop as early as after the first dose to years after ICI initiation. Most irAEs resolve pharmacologically, but some appear to be persistent. Glucocorticoids represent the mainstay of management of irAEs, but other immunosuppressive drugs can be used to mitigate refractory irAEs. In the absence of specific trials, several guidelines, based on data from retrospective studies and expert consensus, have been published to guide the management of ICI-related irAEs.

Fecal microbiota transplantation and Clostridioides difficile infection among privately insured patients in the United States

BACKGROUND

Clostridioides difficile infection (CDI) may be rising in severity in the US over the past decade and its treatment landscape is changing given the recent adoption of fecal microbiota transplantation (FMT) METHODS: We built a retrospective observational cohort using a database of a national care-plan containing medical claims of over 50 million individuals between 2008 and 2019. We used International Classification of Disease (ICD) and prescription data to identify patients with CDI. We estimated trends in disease burden and FMT use, and evaluated complications post FMT using a phenome-wide association approach.

RESULTS

We identified 38,396 patients with CDI; the median age was 60 years (IQR 45-74) and 60% were female (n = 23,374). The rate of CDI increased from 33.4 to 69.46 cases per 100,000 person-years between 2008 and 2015, and stabilized from 2015 to 2019 (increase of 4.77 cases per 100,000 person-years per year, 95% CI 3.55-5.98 prior to 2015 vs. 2.01 95% CI - 10.16 to 14.18 after 2015). Of the 7715 patients with recurrent CDI, 407 patients (5%) underwent FMT. Gastrointestinal complications were increased within 1 month post FMT (OR 99.60, p < 0.001). Sepsis was identified in two individuals (0.49% 95% CI 0.05-1.7%) within the first month post FMT. The risk of CDI recurrence significantly decreased post FMT compared with anti-CDI antibiotics in the multivariable model (raw-recurrence rate 9.8% vs 36%, aOR = 0.21, 95% CI 0.12-0.53, p < 0.001).

CONCLUSION

We show that FMT is strongly associated with a decrease in CDI recurrence compared with the usual care with generally mild complications for up to 2 years.

Gut Microbiome and Common Variable Immunodeficiency: Few Certainties and Many Outstanding Questions

Common variable immunodeficiency (CVID) is the most common symptomatic primary antibody immunodeficiency, characterized by reduced serum levels of IgG, IgA, and/or IgM. The vast majority of CVID patients have polygenic inheritance. Immune dysfunction in CVID can frequently involve the gastrointestinal tract and lung. Few studies have started to investigate the gut microbiota profile in CVID patients. Overall, the results suggest that in CVID patients there is a reduction of alpha and beta diversity compared to controls. In addition, these patients can exhibit increased plasma levels of lipopolysaccharide (LPS) and markers (sCD14 and sCD25) of systemic immune cell activation. CVID patients with enteropathy exhibit decreased IgA expression in duodenal tissue. Mouse models for CVID unsatisfactorily recapitulate the polygenic causes of human CVID. The molecular pathways by which gut microbiota contribute to systemic inflammation and possibly tumorigenesis in CVID patients remain poorly understood. Several fundamental questions concerning the relationships between gut microbiota and the development of chronic inflammatory conditions, autoimmune disorders or cancer in CVID patients remain unanswered. Moreover, it is unknown whether it is possible to modify the microbiome and the outcome of CVID patients through specific therapeutic interventions.

Engineering the Microbiome to Prevent Adverse Events: Challenges and Opportunities

In the past decade of microbiome research, we have learned about numerous adverse interactions between the microbiome and medical interventions such as drugs, radiation, and surgery. What if we could alter our microbiomes to prevent these events? In this review, we discuss potential routes to mitigate microbiome adverse events, including applications from the emerging field of microbiome engineering. We highlight cases where the microbiome acts directly on a treatment, such as via differential drug metabolism, and cases where a treatment directly harms the microbiome, such as in radiation therapy. Understanding and preventing microbiome adverse events is a difficult challenge that will require a data-driven approach involving causal statistics, multiomics techniques, and a personalized means of mitigating adverse events. We propose research considerations to encourage productive work in preventing microbiome adverse events, and we highlight the many challenges and opportunities that await.

Fecal Microbiota Transplant: Latest Addition to Arsenal Against Recurrent Clostridium Difficile Infection

An infectious disease of colon, recurrent Clostridium difficile infection (RCDI) is hitherto considered insurmountable leading to significant morbidity and mortality. Gut dysbiosis, generally resulting from frequent use of antibiotics is considered to be responsible for the etiopathogenesis of rCDI. Ironically, the conventional treatment strategies for the disease also include the use of anti-infective drugs such as metronidazole, vancomycin and fidaxomycin. As a result of the efforts to overcome the limitations of these treatment options to control recurrence of disease, Fecal Microbiota Transplant (FMT) has emerged as an effective and safe alternative. It is pertinent to add here that FMT is defined as the process of engraftment of fecal suspension from the healthy person into the gastrointestinal tract of the diseased individual aiming at the restoration of gut microbiota. FMT has proved to be quite successful in the treatment of recurrent and resistant Clostridium difficile infections (RCDI). In last three decades a lot of information has been generated on the use of FMT for RCDI. A number of clinical trials have been reported with generally very high success rates. However, very small number of patents could be found in the area indicating that there still exists lacuna in the knowledge about FMT with respect to its preparation, regulation, mode of delivery and safety. The current review attempts to dive deeper to discuss the patents available in the area while supporting the information contained therein with the non-patent literature.

Evolution of animal immunity in the light of beneficial symbioses

Immune system processes serve as the backbone of animal defences against pathogens and thus have evolved under strong selection and coevolutionary dynamics. Most microorganisms that animals encounter, however, are not harmful, and many are actually beneficial. Selection should act on hosts to maintain these associations while preventing exploitation of within-host resources. Here, we consider how several key aspects of beneficial symbiotic associations may shape host immune system evolution. When host immunity is used to regulate symbiont populations, there should be selection to evolve and maintain targeted immune responses that recognize symbionts and suppress but not eliminate symbiont populations. Associating with protective symbionts could relax selection on the maintenance of redundant host-derived immune responses. Alternatively, symbionts could facilitate the evolution of host immune responses if symbiont-conferred protection allows for persistence of host populations that can then adapt. The trajectory of immune system evolution will likely differ based on the type of immunity involved, the symbiont transmission mode and the costs and benefits of immune system function. Overall, the expected influence of beneficial symbiosis on immunity evolution depends on how the host immune system interacts with symbionts, with some interactions leading to constraints while others possibly relax selection on immune system maintenance. This article is part of the theme issue 'The role of the microbiome in host evolution'.

A secondary bile acid from microbiota metabolism attenuates ileitis and bile acid reduction in subclinical necrotic enteritis in chickens

Background

Clostridium perfringens-induced chicken necrotic enteritis (NE) is responsible for substantial economic losses worldwide annually. Recently, as a result of antibiotic growth promoter prohibition, the prevalence of NE in chickens has reemerged. This study was aimed to reduce NE through titrating dietary deoxycholic acid (DCA) as an effective antimicrobial alternative.

Materials and methods

Day-old broiler chicks were assigned to six groups and fed diets supplemented with 0 (basal diet), 0.8, 1.0 and 1.5 g/kg (on top of basal diet) DCA. The birds were challenged with Eimeria maxima (20,000 oocysts/bird) at d 18 and C. perfringens (10⁹ CFU/bird per day) at d 23, 24, and 25 to induce NE. The birds were sacrificed at d 26 when ileal tissue and digesta were collected for analyzing histopathology, mRNA accumulation and C. perfringens colonization by real-time PCR, targeted metabolomics of bile acids, fluorescence in situ hybridization (FISH), or terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay.

Results

At the cellular level, birds infected with E. maxima and C. perfringens developed subclinical NE and showed shortening villi, crypt hyperplasia and immune cell infiltration in ileum. Dietary DCA alleviated the NE-induced ileal inflammation in a dose-dependent manner compared to NE control birds. Consistent with the increased histopathological scores, subclinical NE birds suffered body weight gain reduction compared to the uninfected birds, an effect attenuated with increased doses of dietary DCA. At the molecular level, the highest dose of DCA at 1.5 g/kg reduced C. perfringens luminal colonization compared to NE birds using PCR and FISH. Furthermore, the dietary DCA reduced subclinical NE-induced intestinal inflammatory gene expression and cell apoptosis using PCR and TUNEL assays. Upon further examining ileal bile acid pool through targeted metabolomics, subclinical NE reduced the total bile acid level in ileal digesta compared to uninfected birds. Notably, dietary DCA increased total bile acid and DCA levels in a dose-dependent manner compared to NE birds.

Conclusion

These results indicate that DCA attenuates NE-induced intestinal inflammation and bile acid reduction and could be an effective antimicrobial alternative against the intestinal disease.

Diet-microbiome-disease: Investigating diet's influence on infectious disease resistance through alteration of the gut microbiome

Abiotic and biotic factors can affect host resistance to parasites. Host diet and host gut microbiomes are two increasingly recognized factors influencing disease resistance. In particular, recent studies demonstrate that (1) particular diets can reduce parasitism; (2) diets can alter the gut microbiome; and (3) the gut microbiome can decrease parasitism. These three separate relationships suggest the existence of indirect links through which diets reduce parasitism through an alteration of the gut microbiome. However, such links are rarely considered and even more rarely experimentally validated. This is surprising because there is increasing discussion of the therapeutic potential of diets and gut microbiomes to control infectious disease. To elucidate these potential indirect links, we review and examine studies on a wide range of animal systems commonly used in diet, microbiome, and disease research. We also examine the relative benefits and disadvantages of particular systems for the study of these indirect links and conclude that mice and insects are currently the best animal systems to test for the effect of diet-altered protective gut microbiomes on infectious disease. Focusing on these systems, we provide experimental guidelines and highlight challenges that must be overcome. Although previous studies have recommended these systems for microbiome research, here we specifically recommend these systems because of their proven relationships between diet and parasitism, between diet and the microbiome, and between the microbiome and parasite resistance. Thus, they provide a sound foundation to explore the three-way interaction between diet, the microbiome, and infectious disease.

Microbial metabolite deoxycholic acid controls Clostridium perfringens-induced chicken necrotic enteritis through attenuating inflammatory cyclooxygenase signaling

Necrotic enteritis (NE) caused by Clostridium perfringens infection has reemerged as a prevalent poultry disease worldwide due to reduced usage of prophylactic antibiotics under consumer preferences and regulatory pressures. The lack of alternative antimicrobial strategies to control this disease is mainly due to limited insight into the relationship between NE pathogenesis, microbiome, and host responses. Here we showed that the microbial metabolic byproduct of secondary bile acid deoxycholic acid (DCA), at as low as 50 µM, inhibited 82.8% of C. perfringens growth in Tryptic Soy Broth (P < 0.05). Sequential Eimeria maxima and C. perfringens challenges significantly induced NE, severe intestinal inflammation, and body weight (BW) loss in broiler chickens. These negative effects were diminished (P < 0.05) by 1.5 g/kg DCA diet. At the cellular level, DCA alleviated NE-associated ileal epithelial death and significantly reduced lamina propria cell apoptosis. Interestingly, DCA reduced C. perfringens invasion into ileum (P < 0.05) without altering the bacterial ileal luminal colonization. Molecular analysis showed that DCA significantly reduced inflammatory mediators of Infγ, Litaf, Il1β, and Mmp9 mRNA accumulation in ileal tissue. Mechanism studies revealed that C. perfringens induced (P < 0.05) elevated expression of inflammatory mediators of Infγ, Litaf, and Ptgs2 (Cyclooxygenases-2 (COX-2) gene) in chicken splenocytes. Inhibiting the COX signaling by aspirin significantly attenuated INFγ-induced inflammatory response in the splenocytes. Consistent with the in vitro assay, chickens fed 0.12 g/kg aspirin diet protected the birds against NE-induced BW loss, ileal inflammation, and intestinal cell apoptosis. In conclusion, microbial metabolic product DCA prevents NE-induced BW loss and ileal inflammation through attenuating inflammatory response. These novel findings of microbiome protecting birds against NE provide new options on developing next generation antimicrobial alternatives against NE.

Factors affecting the composition of the gut microbiota, and its modulation

Gut microbiota have important functions in the body, and imbalances in the composition and diversity of those microbiota can cause several diseases. The host fosters favorable microbiota by releasing specific factors, such as microRNAs, and nonspecific factors, such as antimicrobial peptides, mucus and immunoglobulin A that encourage the growth of specific types of bacteria and inhibit the growth of others. Diet, antibiotics, and age can change gut microbiota, and many studies have shown the relationship between disorders of the microbiota and several diseases and reported some ways to modulate that balance. In this review, we highlight how the host shapes its gut microbiota via specific and nonspecific factors, how environmental and nutritional factors affect it, and how to modulate it using prebiotics, probiotics, and fecal microbiota transplantation.

Community analysis and co-occurrence patterns in airway microbial communities during health and disease

Ecological relationships between bacteria are important when considering variation in bacterial communities in humans, with such variation playing an important role in both health and disease.

Using high-throughput sequence data of the 16S rRNA marker-gene, we analysed the prevalence of taxa in the airways of a number of health- and disease-associated cohorts and determined the main drivers of community variance and bacterial co-occurrence.

A number of facultative and obligately anaerobic bacterial taxa are commonly associated with the upper airways, forming the main “core” microbiota, e.g. Streptococcus spp., Veillonella spp., Prevotella spp., Granulicatella spp. and Fusobacterium spp. Opportunistic pathogenic bacteria associated with chronic airways disease, such as Pseudomonas spp. (Pseudomonas aeruginosa), Burkholderia spp. (Burkholderia cepacia complex) and Haemophilus spp. (Haemophilus influenzae) demonstrated poor correlation with other members of their respective communities (ρ<0.5; p>0.005), indicating probable independent acquisition and colonisation. Furthermore, our findings suggest that intra-genus variation between health and disease may affect community assemblies.

Improved understanding of how bacteria assemble in time and space during health and disease will enable the future development of tailored treatment according to the patient's own signature microbiota, potentially providing benefit to patients suffering from airway diseases characterised by chronic infection.

Within the airways, “core” community structures are formed between microbial taxa in both health and disease, with a number of common opportunistic pathogens not being members of such core communitieshttp://bit.ly/2Kau3ni

Microbial metabolite deoxycholic acid shapes microbiota against Campylobacter jejuni chicken colonization

Despite reducing the prevalent foodborne pathogen Campylobacter jejuni in chickens decreases campylobacteriosis, few effective approaches are available. The aim of this study was to use microbial metabolic product bile acids to reduce C. jejuni chicken colonization. Broiler chicks were fed with deoxycholic acid (DCA), lithocholic acid (LCA), or ursodeoxycholic acid (UDCA). The birds were also transplanted with DCA modulated anaerobes (DCA-Anaero) or aerobes (DCA-Aero). The birds were infected with human clinical isolate C. jejuni 81-176 or chicken isolate C. jejuni AR101. Notably, C. jejuni 81-176 was readily colonized intestinal tract at d16 and reached an almost plateau at d21. Remarkably, DCA excluded C. jejuni cecal colonization below the limit of detection at 16 and 28 days of age. Neither chicken ages of infection nor LCA or UDCA altered C. jejuni AR101 chicken colonization level, while DCA reduced 91% of the bacterium in chickens at d28. Notably, DCA diet reduced phylum Firmicutes but increased Bacteroidetes compared to infected control birds. Importantly, DCA-Anaero attenuated 93% of C. jejuni colonization at d28 compared to control infected birds. In conclusion, DCA shapes microbiota composition against C. jejuni colonization in chickens, suggesting a bidirectional interaction between microbiota and microbial metabolites.

Recurrent Clostridium difficile Infection: Risk Factors, Treatment, and Prevention

The most common cause of antibiotic-associated diarrhea is Clostridium difficile infection (CDI). Recurrent C. difficile infection (rCDI) often occurs after successful treatment of CDI. Due to the increased incidence and the difficulty in treating rCDI, it is becoming an important clinical issue. Identifying risk factors is helpful for early detection, treatment, and prevention of rCDI. Advanced age, use of antibiotics, gastric acid suppression, and infection with a hypervirulent strain are currently regarded as the major risk factors for rCDI. Several treatment modalities, including vancomycin, fidaxomicin, and fecal microbiota transplant (FMT), are suggested for rCDI treatment. However, there is currently no definitive treatment method with sufficient evidence for rCDI. Recent studies have focused on FMT and have shown positive results for rCDI. Prevention of rCDI by measures such as hand washing and isolation of patients is very important. However, these preventive measures are often overlooked in clinical practice. Here, we review the risk factors, treatment, and prevention of rCDI.

Fecal microbiota transplantation: donor relation, fresh or frozen, delivery methods, cost-effectiveness

Fecal microbiota transplantation (FMT) has evolved into a robust and efficient means for treating recurrent Clostridium difficile infection (CDI). Our narrative review looks at the donor selection, preparation, delivery techniques and cost-effectiveness of FMT. We searched electronic databases, including PubMed, MEDLINE, Google Scholar, and Cochrane Databases, for studies that compared the biological effects of donor selection, fresh or frozen fecal preparation, and various delivery techniques. We also evaluated the cost-effectiveness and manually searched references to identify additional relevant studies. Overall, there is a paucity of studies that directly compare outcomes associated with related and non-related stool donors. However, inferences from prior studies indicate that the success of FMT does not depend on the donor-patient relationship. Over time, the use of unrelated donors has increased because of the formation of stool banks and the need to save processing time and capital. However, longitudinal studies are needed to clarify the optimal freezing time before microbial function declines. Several FMT techniques have been developed, such as colonoscopy, enema, nasogastric or nasojejunal tubes, and capsules. The comparable and high efficacy of FMT capsules, combined with their convenience, safety and aesthetically tolerable mode of delivery, makes it an attractive option for many patients. Cost-effective models comparing these various approaches support the use of FMT via colonoscopy as being the best strategy for the treatment of recurrent CDI.

Microbiome modulates intestinal homeostasis against inflammatory diseases

Eliminating prophylactic antibiotics in food animal production has exerted pressure on discovering antimicrobial alternatives (e.g. microbiome) to reduce elevated intestinal diseases. Intestinal tract is a complex ecosystem coupling host cells with microbiota. The microbiota and its metabolic activities and products are collectively called microbiome. Intestinal homeostasis is reached through dynamic and delicate crosstalk between host immunity and microbiome. However, this balance can be occasionally broken, which results in intestinal inflammatory diseases such as human Inflammatory Bowel Diseases, chicken necrotic enteritis, and swine postweaning diarrhea. In this review, we introduce the intestinal immune system, intestinal microbiome, and microbiome modulation of inflammation against intestinal diseases. The purpose of this review is to provide updated knowledge on host-microbe interaction and to promote using microbiome as new antimicrobial strategies to reduce intestinal diseases.

Process and Outcome of Fecal Microbiota Transplants in Patients With Recurrent Clostridium difficile Infection: A Prospective Study

The incidence of Clostridium difficile infection is on the rise worldwide, causing high mortality rates and costing patients, hospitals, and insurance companies millions of dollars annually. Fecal microbiota transplants successfully treat recurrent C. difficile infections unresponsive to standard pharmacologic treatment such as flagyl, vancomycin, or rifaximin. Evidence in the literature provided the foundation for the development and refinement of this fecal microbiota transplant protocol. During the initial phase of the project, the protocol included patient selection criteria, donor screening/selection, infection control, fecal processing and delivery, and patient pre and postprocedure education. This article highlights the second phase of prospective testing of a nurse-driven protocol to implement fecal microbiota transplantation in patients with recurrent C. difficile infection. All stages of the protocol are explained as well as rationale for component parts to achieve successful patient outcomes when the protocol is carefully followed.

A Systematic Review of the Efficacy and Safety of Fecal Microbiota Transplant for Clostridium difficile Infection in Immunocompromised Patients

Background

Fecal microbiota transplantation (FMT) has been shown to be effective in recurrent Clostridium difficile (CD) infection, with resolution in 80% to 90% of patients. However, immunosuppressed patients were often excluded from FMT trials, so safety and efficacy in this population are unknown.

Methods

We searched MEDLINE and EMBASE for English language articles published on FMT for treatment of CD infection in immunocompromised patients (including patients on immunosuppressant medications, patients with human immunodeficiency virus (HIV), inherited or primary immunodeficiency syndromes, cancer undergoing chemotherapy, or organ transplant, including-bone marrow transplant) of all ages. We excluded inflammatory bowel disease patients that were not on immunosuppressant medications. Resolution and adverse event rates (including secondary infection, rehospitalization, and death) were calculated.

Results

Forty-four studies were included, none of which were randomized designs. A total of 303 immunocompromised patients were studied. Mean patient age was 57.3 years. Immunosuppressant medication use was the reason for the immunocompromised state in the majority (77.2%), and 19.2% had greater than one immunocompromising condition. Seventy-six percent were given FMT via colonoscopy. Of the 234 patients with reported follow-up outcomes, 207/234 (87%) reported resolution after first treatment, with 93% noting success after multiple treatments. There were 2 reported deaths, 2 colectomies, 5 treatment-related infections, and 10 subsequent hospitalizations.

Conclusion

We found evidence that supports the use of FMT for treatment of CD infection in immunocompromised patients, with similar rates of serious adverse events to immunocompetent patients.

Control of Clostridium difficile Infection by Defined Microbial Communities

Each year in the United States, billions of dollars are spent combating almost half a million Clostridium difficile infections (CDIs) and trying to reduce the ∼29,000 patient deaths in which C. difficile has an attributed role. In Europe, disease prevalence varies by country and level of surveillance, though yearly costs are estimated at €3 billion. One factor contributing to the significant health care burden of C. difficile is the relatively high frequency of recurrent CDIs. Recurrent CDI, i.e., a second episode of symptomatic CDI occurring within 8 weeks of successful initial CDI treatment, occurs in ∼25% of patients, with 35 to 65% of these patients experiencing multiple episodes of recurrent disease. Using microbial communities to treat recurrent CDI, either as whole fecal transplants or as defined consortia of bacterial isolates, has shown great success (in the case of fecal transplants) or potential promise (in the case of defined consortia of isolates). This review will briefly summarize the epidemiology and physiology of C. difficile infection, describe our current understanding of how fecal microbiota transplants treat recurrent CDI, and outline potential ways that knowledge can be used to rationally design and test alternative microbe-based therapeutics.

Microbiota-Derived Metabolic Factors Reduce Campylobacteriosis in Mice

BACKGROUND & AIMS

Campylobacter jejuni, a prevalent foodborne bacterial pathogen, exploits the host innate response to induce colitis. Little is known about the roles of microbiota in C jejuni-induced intestinal inflammation. We investigated interactions between microbiota and intestinal cells during C jejuni infection of mice.

METHODS

Germ-free C57BL/6 Il10-/- mice were colonized with conventional microbiota and infected with a single dose of C jejuni (109 colony-forming units/mouse) via gavage. Conventional microbiota were cultured under aerobic, microaerobic, or anaerobic conditions and orally transplanted into germ-free Il10-/- mice. Colon tissues were collected from mice and analyzed by histology, real-time polymerase chain reaction, and immunoblotting. Fecal microbiota and bile acids were analyzed with 16S sequencing and high-performance liquid chromatography with mass spectrometry, respectively.

RESULTS

Introduction of conventional microbiota reduced C jejuni-induced colitis in previously germ-free Il10-/- mice, independent of fecal load of C jejuni, accompanied by reduced activation of mammalian target of rapamycin. Microbiota transplantation and 16S ribosomal DNA sequencing experiments showed that Clostridium XI, Bifidobacterium, and Lactobacillus were enriched in fecal samples from mice colonized with microbiota cultured in anaerobic conditions (which reduce colitis) compared with mice fed microbiota cultured under aerobic conditions (susceptible to colitis). Oral administration to mice of microbiota-derived secondary bile acid sodium deoxycholate, but not ursodeoxycholic acid or lithocholic acid, reduced C jejuni-induced colitis. Depletion of secondary bile acid-producing bacteria with antibiotics that kill anaerobic bacteria (clindamycin) promoted C jejuni-induced colitis in specific pathogen-free Il10-/- mice compared with the nonspecific antibiotic nalidixic acid; colitis induction by antibiotics was associated with reduced level of luminal deoxycholate.

CONCLUSIONS

We identified a mechanism by which the microbiota controls susceptibility to C jejuni infection in mice, via bacteria-derived secondary bile acids.

Fecal Microbiota Therapy With a Focus on Clostridium difficile Infection

There has been a paradigm shift in our view of bacteria away from their role as just pathogens. We now have a deepening appreciation of their critical influences in our health maintenance, including energy harvest, metabolism, intestinal development, cell proliferation, nervous system and immune function, as well as their role to protect against intestinal and other infections. A perturbed intestinal microbiome has been associated with an increasing number of gastrointestinal and nongastrointestinal diseases but particularly with Clostridium difficile infection (CDI). Although such association does not imply causation, it has been shown that fecal microbiota transplantation (FMT) can correct the dysbiosis that characterizes chronic and recurring CDI and that FMT can effect a seemingly safe and rapidly effective cure for most patients with CDI so treated. FMT has been used to treat a wide range of other diseases, although conclusions about efficacy in any disease other than CDI must await appropriate well-designed trials. More work needs to be conducted with FMT, especially to evaluate and ensure its long-term safety. Future studies are likely to narrow the spectrum of organisms that needs to be given to patients to cure CDI, and perhaps other diseases, and to elucidate the mechanisms whereby such therapeutic benefit occurs. FMT is but the first step in this journey.

Coordinated Hospital-Home Fecal Microbiota Transplantation via Percutaneous Endoscopic Cecostomy for Recurrent Steroid-Dependent Ulcerative Colitis

Since its introduction as an alternative intestinal microbiota alteration approach, fecal microbiota transplantation (FMT) has been increasingly used as a treatment of choice for patients with ulcerative colitis (UC), but no reports exist regarding FMT via percutaneous endoscopic cecostomy (PEC). This report describes the case of a 24-year-old man with a 7-year history of recurrent, steroid-dependent UC. He received FMT via PEC once per day for 1 month in the hospital. After the remission of gastrointestinal symptoms, he was discharged from the hospital and continued FMT via PEC twice per week for 3 months at home. The frequency of stools decreased, and the characteristics of stools improved soon thereafter. Enteral nutrition was regained after 1 week, and an oral diet was begun 1 month later. Two months after the FMT end point, the patient resumed a normal diet, with formed soft stools once per day. The follow-up colonoscopy showed normal mucus membranes; then, the PEC set was removed. On the subsequent 12 months follow-up, the patient resumed orthobiosis without any gastrointestinal discomfort and returned to work. This case emphasizes that FMT via PEC can not only induce remission but also shorten the duration of hospitalization and reduce the medical costs; therefore, this approach should be considered an alternative option for patients with UC.

Upper Versus Lower Gastrointestinal Delivery for Transplantation of Fecal Microbiota in Recurrent or Refractory Clostridium difficile Infection: A Collaborative Analysis of Individual Patient Data From 14 Studies

GOALS

The aim of this study was to compare upper gastrointestinal (UGI) versus lower gastrointestinal (LGI) delivery routes of fecal microbiota transplantation (FMT) for refractory or recurrent/relapsing Clostridium difficile infection (CDI).

BACKGROUND

FMT has been proven to be a safe and highly effective therapeutic option for CDI. Delivery, however, could be via the UGI or LGI routes, and it is unclear as to which route provides better clinical outcome.

STUDY

A systematic search for studies that reported the use of FMT for CDI treatment was conducted. Individual patient data that included demographic (age and sex) and clinical (route of FMT delivery, CDI outcome after FMT, and follow-up time) information were obtained. Kaplan-Meier cumulative hazard curves and Cox proportional hazard models were used to assess clinical failure after FMT by the route of delivery.

RESULTS

Data from 305 patients treated with FMT (208 via LGI route and 97 via UGI route) for CDI were analyzed. At 30 and 90 days, the risk of clinical failure was 5.6% and 17.9% in the UGI group compared with 4.9% and 8.5% in the LGI delivery route group, respectively. A time-varying analysis suggested a 3-fold increase in hazard of clinical failure for UGI delivery (hazard ratio, 3.43; 95% confidence interval, 1.32-8.93) in the period after 30 days.

CONCLUSIONS

FMT delivered via the LGI seems to be the most effective route for the prevention of recurrence/relapse of CDI. A randomized controlled trial is necessary to confirm whether FMT delivered via the LGI is indeed superior to that delivered via the UGI route.

Cost-Effectiveness Analysis of Five Competing Strategies for the Management of Multiple Recurrent Community-Onset Clostridium difficile Infection in France

Background

Clostridium difficile infection (CDI) is characterized by high rates of recurrence, resulting in substantial health care costs. The aim of this study was to analyze the cost-effectiveness of treatments for the management of second recurrence of community-onset CDI in France.

Methods

We developed a decision-analytic simulation model to compare 5 treatments for the management of second recurrence of community-onset CDI: pulsed-tapered vancomycin, fidaxomicin, fecal microbiota transplantation (FMT) via colonoscopy, FMT via duodenal infusion, and FMT via enema. The model outcome was the incremental cost-effectiveness ratio (ICER), expressed as cost per quality-adjusted life year (QALY) among the 5 treatments. ICERs were interpreted using a willingness-to-pay threshold of €32,000/QALY. Uncertainty was evaluated through deterministic and probabilistic sensitivity analyses.

Results

Three strategies were on the efficiency frontier: pulsed-tapered vancomycin, FMT via enema, and FMT via colonoscopy, in order of increasing effectiveness. FMT via duodenal infusion and fidaxomicin were dominated (i.e. less effective and costlier) by FMT via colonoscopy and FMT via enema. FMT via enema compared with pulsed-tapered vancomycin had an ICER of €18,092/QALY. The ICER for FMT via colonoscopy versus FMT via enema was €73,653/QALY. Probabilistic sensitivity analysis with 10,000 Monte Carlo simulations showed that FMT via enema was the most cost-effective strategy in 58% of simulations and FMT via colonoscopy was favored in 19% at a willingness-to-pay threshold of €32,000/QALY.

Conclusions

FMT via enema is the most cost-effective initial strategy for the management of second recurrence of community-onset CDI at a willingness-to-pay threshold of €32,000/QALY.

Clostridium difficile colitis: A clinical review

BACKGROUND

Clostridium difficile colitis is an important cause of morbidity and mortality in the surgical patient. In recent years, Clostridium difficile infections have shown marked increases in frequency, severity, and resistance to standard treatment. With urgent operative interventions and novel endoscopic approaches, pseudomembranous colitis is being seen more commonly in surgical practices.

DATA SOURCES

In this paper, we will review a number of papers from the literature. We will discuss the epidemiology, evaluation and treatment of Clostridium difficile infection. Fulminant colitis may require emergency operation. For the surgical endoscopist, fecal microbiota transplantation restores the gastrointestinal flora, and has been shown to be effective in more than 80% of patients.

CONCLUSION

Clostridium difficile infection is a major cause of healthcare-related diarrhea leading to increased morbidity and mortality in surgical patients. Increases in failure rates and resistance to current treatments are clinical and economic challenges in the healthcare situation.

Fecal microbiota transplant to treat recurrent Clostridium difficile infections

The prevalence of recurrent or refractory Clostridium difficile infection has been steadily increasing since 2000. Consequently, alternative treatments to the standard antibiotic therapies are now being considered. One alternative treatment is fecal microbiota transplant. Although fecal microbiota transplant is relatively new--and not appealing to most people--it has been around for many years and has great promise as an inexpensive, safe, and efficient treatment of refractory and recurrent C difficile infection. With a better understanding of the intricacies of the colonic microbiome and its role in colonic physiology and pathophysiology, critical care nurses will recognize that fecal microbiota transplant has the potential to become the standard of care for treatment of recurrent or refractory C difficile infection. The American College of Gastroenterology and the Infectious Diseases Society of America provide the latest treatment guidelines for care of patients with these clostridial infections.

Challenges in management of recurrent and refractory Clostridium difficile infection

Clostridium difficile infection (CDI) is the most common nosocomial infection in the United States and is associated with a high mortality. One quarter of patients treated for CDI have at least one recurrence. Spore persistence, impaired host immune response and alteration in the gastrointestinal microbiome due to antibiotic use are factors in recurrent disease. We review the etiology of recurrent CDI and best approaches to management including fecal microbiota transplantation.

Systematic Review: Adverse Events of Fecal Microbiota Transplantation

BACKGROUND

Fecal microbiota transplantation (FMT) is a microbiota-based therapy that shows therapeutic potential in recurrent or refractory Clostridium difficile infections and other intestinal or extra-intestinal disorders. Nonetheless, adverse events (AEs) remain a major challenge in the application of FMT.

AIM

To review the AEs of FMT and to address the concerns of safety during the procedure.

METHODS

Publications were retrieved in the databases of Medline, Embase and Cochrane Library. AEs were classified according to their causality with FMT or their severity.

RESULTS

A total of 7562 original articles about FMT were identified in this study, 50 of them fulfilled the inclusion criteria. Totally 78 kinds of AEs were revealed enrolled in these 50 selected publications. The total incidence rate of AEs was 28.5%. Among the 42 publications, 5 kinds were definitely and 38 kinds were probably related to FMT. The commonest FMT-attributable AE was abdominal discomfort, which was reported in 19 publications. For upper gastrointestinal routes of FMT, 43.6% (89/204) patients were compromised by FMT-attributable AE, while the incidence dropped to 17.7% (76/430) for lower gastrointestinal routes. In contrast, the incidences of serious adverse events (SAEs) were 2.0% (4/196) and 6.1% (40/659) for upper and lower gastrointestinal routes, respectively. A total of 44 kinds of SAEs occurred in 9.2% patients, including death (3.5%, 38/1089), infection (2.5%, 27/1089), relapse of inflammatory bowel diseases (0.6%, 7/1089) and Clostridium difficile infection (0.9%, 10/1089).

CONCLUSION

Consequently, both AEs and SAEs are not rare and should be carefully monitored throughout FMT. However, high quality randomized controlled trials are still needed for the more definite incidence of AEs of FMT.

Fecal Microbiota Transplant

Clostridium difficile infection (CDI) has steadily increased in incidence since the 1990s, with an associated increase in recurrence and severity, which has in turn lead to more intensive care unit (ICU) admissions. The development of recurrent CDI, in particular, has been associated with increasing patient morbidity and mortality as well as an immense financial burden on the health care system. Recently, fecal microbiota transplantation (FMT) has received much publicity as an effective means of treatment for recurrent CDI. The goal of this review is to provide evidence-based recommendations for the diagnosis and management of CDI, with a particular focus on FMT and its utilization in the ICU.

Fecal microbiota transplantation for severe clostridium difficile infection after left ventricular assist device implantation: a case control study and concise review on the local and regional therapies

Background

We report herein a case of fecal microbiota transplantation (FMT) used for severe Clostridium difficile infection for a 65-year-old Lebanese man who underwent left ventricular assist device implantation. To the best of our knowledge this is the first case report from Lebanon and the region presenting such technique.

Case presentation

The patient experienced diarrhea and rectal bleeding and was diagnosed of pseudomembranous colitis (PMC). His condition failed to improve on maximal pharmacological therapy. Protocolectomy, an invasive operation consisting in resection of the entire colon and rectum seemed to be the last resort before the patient responded to FMT given through gastroscopy.

Conclusion

Despite the increasing experience with FMT for C. difficile infection, published evidence in severe related cases from this region is very limited. Hence, we promote adjunctive FMT, an effective noninvasive method, to be considered as a promising early treatment option in severe C. difficile infection.

Long-term Follow-up Study of Fecal Microbiota Transplantation for Severe and/or Complicated Clostridium difficile Infection: A Multicenter Experience

GOAL

Our aim was to investigate fecal microbiota transplantation (FMT) efficacy in patients with severe and/or complicated Clostridium difficile infection (CDI).

BACKGROUND

FMT is successful for recurrent CDI, although its benefit in severe or complicated CDI has not specifically been evaluated.

STUDY METHODS

A multicenter long-term follow-up study was performed in patients who received FMT for severe and/or complicated CDI (diagnosed using standard criteria). Pre-FMT and post-FMT questionnaires were completed. Study outcomes included cure rates and time to resolution of symptoms.

RESULTS

A total of 17 patients (82% inpatients, 18% outpatients) were included (76.4% women; mean age, 66.4 y; mean follow-up, 11.4 mo). Patients had severe and complicated (76.4%) or either severe or complicated (23.6%) CDI. Sixteen patients (94.1%) had diarrhea, which resolved in 12 (75%; mean time to resolution, 5.7 d) and improved in 4 (25%) after FMT. Eleven patients (64.7%) had abdominal pain, which resolved in 8 (72.7%; mean time to resolution, 9.6 d) and improved in 3 (27.3%) after FMT. Two of 17 patients experienced early CDI recurrence (≤90 d) after FMT (primary cure rate, 88.2%); and in 1 patient, a second FMT resulted in cure (secondary cure rate, 94.1%). Late CDI recurrence (≥90 d) was seen in 1 of 17 patients (5.9%) in association with antibiotics and was successfully treated with a repeat FMT. No adverse effects directly related to FMT occurred.

CONCLUSIONS

FMT was successful and safe in this cohort of patients with severe or complicated CDI. Primary and secondary cure rates were 88.2% and 94.1%, respectively.

The New Era of Treatment for Obesity and Metabolic Disorders: Evidence and Expectations for Gut Microbiome Transplantation

Key Points: The microbiome has been implicated in the development of obesity. Conventional therapeutic methods have limited effectiveness for the treatment of obesity and prevention of related complications. Gut microbiome transplantation may represent an alternative and effective therapy for the treatment of obesity. Obesity has reached epidemic proportions. Despite a better understanding of the underlying pathophysiology and growing treatment options, a significant proportion of obese patients do not respond to treatment. Recently, microbes residing in the human gastrointestinal tract have been found to act as an "endocrine" organ, whose composition and functionality may contribute to the development of obesity. Therefore, fecal/gut microbiome transplantation (GMT), which involves the transfer of feces from a healthy donor to a recipient, is increasingly drawing attention as a potential treatment for obesity. Currently the evidence for GMT effectiveness in the treatment of obesity is preliminary. Here, we summarize benefits, procedures, and issues associated with GMT, with a special focus on obesity.

Fecal microbiota transplantation for Clostridium difficile infection: back to the future

INTRODUCTION

Clostridium difficile infection (CDI) is a leading cause of diarrhea in the industrialized world. The estimated costs of this infection are impressive: over 3.2 billion dollars annually in the US. The introduction of fecal microbiota transplantation (FMT) to clinical practice can be considered a Copernican Revolution. The rationale of this approach consists of correcting the imbalance of the organisms dwelling in the gut by reintroducing a normal flora.

AREAS COVERED

This review focuses on the indication for FMT in CDI; it examines in-depth the most relevant aspects of the techniques used, and the safety and efficacy of this new 'old' therapy.

EXPERT OPINION

Authoritative guidelines about the management of CDI strongly recommend FMT for multiple recurrent episodes of infection by C. difficile unresponsive to repeated antibiotic treatment. The cure rates are about 90%, with no serious adverse events having been reported. The main concerns are the long-term outcomes, lack of a standardized procedure for the delivery of donor material, and a cultural barrier to the transplantation of fecal microbiota. A promising solution to some of these problems could be the use of a more acceptable administration route of fecal material, namely, oral capsules.

Colonization potential to reconstitute a microbe community in patients detected early after fecal microbe transplant for recurrent C. difficile

Background

Fecal microbiota transplants (FMT) are an effective treatment for patients with gut microbe dysbiosis suffering from recurrent C. difficile infections. To further understand how FMT reconstitutes the patient’s gut commensal microbiota, we have analyzed the colonization potential of the donor, recipient and recipient post transplant fecal samples using transplantation in gnotobiotic mice.

Results

A total of nine samples from three human donors, recipient’s pre and post FMT were transplanted into gnotobiotic mice. Microbiome analysis of three donor fecal samples revealed the presence of a high relative abundance of commensal microbes from the family Bacteriodaceae and Lachnospiraceae that were almost absent in the three recipient pre FMT fecal samples (<0.01 %). The microbe composition in gnotobiotic mice transplanted with the donor fecal samples was similar to the human samples. The recipient samples contained Enterobacteriaceae, Lactobacillaceae, Enterococcaceae in relative abundance of 43, 11, 8 %, respectively. However, gnotobiotic mice transplanted with the recipient fecal samples had an average relative abundance of unclassified Clostridiales of 55 %, approximately 7000 times the abundance in the recipient fecal samples prior to transplant. Microbiome analysis of fecal samples from the three patients early (2–4 weeks) after FMT revealed a microbe composition with the relative abundance of both Bacteriodaceae and Lachnospiraceae that was approximately 7 % of that of the donor. In contrast, gnotobioitc mice transplanted with the fecal samples obtained from the three at early times post FMT revealed increases in the relative abundance of Bacteriodaceae and Lachnospiraceae microbe compositions to levels similar to the donor fecal samples. Furthermore, the unclassified Clostridiales in the recipient samples post FMT was reduced to an average of 10 %.

Conclusion

We have used transplantation into gnotobiotic mice to evaluate the colonization potential of microbiota in FMT patients early after transplant. The commensal microbes present at early times post FMT out competed non-commensal microbes (e.g. such as unclassified Clostridiales) for niche space. The selective advantage of these commensal microbes to occupy niches in the gastrointestinal tract helps to explain the success of FMT to reconstitute the gut microbe community of patients with recurrent C. difficile infections.

Electronic supplementary material

The online version of this article (doi:10.1186/s12866-015-0622-2) contains supplementary material, which is available to authorized users.

Recurrent Clostridium difficile infection and the microbiome

The diverse and densely populated gastrointestinal microbiota is essential for the regulation of host physiology and immune function. As our knowledge of the composition and function of the intestinal microbiota continues to expand, there is new interest in using these developments to tailor fecal microbiota transplantation (FMT) and microbial ecosystem therapeutics (MET) for a variety of diseases. The potential role of FMT and MET in the treatment of Clostridium difficile infection (CDI)-currently the leading nosocomial gastrointestinal infection-has proven highly effective for recurrent CDI, and has emerged as a paradigm shift in the treatment of this disease. The current review will serve as a summary of the key aspects of CDI, and will introduce the essential framework and challenges of FMT, as is currently practiced. MET represents the progression of conventional bacteriotherapy that fundamentally capitalizes on the restorative properties of intestinal bacterial communities and may be viewed as the culmination of a rationally designed therapeutic modality. As our understanding of the composition and function of the intestinal microbiota evolves, it will likely drive next-generation microbiota therapies for a range of medical conditions, such as inflammatory bowel disease, obesity, and metabolic syndrome.

Clostridium Difficile Infection Due to Pneumonia Treatment: Mortality Risk Models

One of the most common gastrointestinal infection after the antibiotic treatment of community or nosocomial pneumonia is caused by the anaerobic spore Clostridium difficile (C. difficile). The aim of this study was to retrospectively assess mortality due to C. difficile infection (CDI) in patients treated for pneumonia. We identified 94 cases of post-pneumonia CDI out of the 217 patients with CDI. The mortality issue was addressed by creating a mortality risk models using logistic regression and multivariate fractional polynomial analysis. The patients' demographics, clinical features, and laboratory results were taken into consideration. To estimate the influence of the preceding respiratory infection, a pneumonia severity scale was included in the analysis. The analysis showed two statistically significant and clinically relevant mortality models. The model with the highest prognostic strength entailed age, leukocyte count, serum creatinine and urea concentration, hematocrit, coexisting neoplasia or chronic obstructive pulmonary disease. In conclusion, we report on two prognostic models, based on clinically relevant factors, which can be of help in predicting mortality risk in C. difficile infection, secondary to the antibiotic treatment of pneumonia. These models could be useful in preventive tailoring of individual therapy.

Fecal microbiota transplantation for the treatment of Clostridium difficile infection

Clostridium difficile, a major cause of healthcare-associated diarrhea due to perturbation of the normal gastrointestinal microbiome, is responsible for significant morbidity, mortality, and healthcare expenditures. The incidence and severity of C difficile infection (CDI) is increasing, and recurrent disease is common. Recurrent infection can be difficult to manage with conventional antibiotic therapy. Fecal microbiota transplantation (FMT), which involves instillation of stool from a healthy donor into the gastrointestinal tract of the patient, restores the gut microbiome to a healthy state. FMT has emerged as a promising new treatment for CDI. There are limited data on FMT for treatment of primary CDI, but FMT appears safe and effective for recurrent CDI. The safety and efficacy of FMT in patients with severe primary or severe recurrent CDI has not been established. Patients with inflammatory bowel disease (IBD) who undergo FMT for CDI may be at increased risk of IBD flare, and caution should be exercised with use of FMT in that population. The long-term safety of FMT is unknown; thus, rigorously conducted prospective studies are needed.

Adverse events in faecal microbiota transplant: a review of the literature

BACKGROUND

Faecal microbiota transplant (FMT) is the infusion of donor faeces into the gut with the aim of improving microbial diversity. The procedure has gained significant interest recently in the treatment of recurrent Clostridium difficile infection (CDI). The literature is currently dominated by small case series and isolated case reports. There is no standardization of methods and recording of outcomes.

AIM

To present the adverse events that have been associated with the use of FMT, as reported in the English literature to date.

METHODS

A database search of Medline and Embase identified publications where FMT has been administered. Review articles were excluded. In total, 109 publications were identified that described the use of FMT in 1555 individuals.

FINDINGS

Other than three small randomized controlled studies, the data consisted of small series and case reports. CDI was the most common indication for FMT (N = 1190), with the majority of the remaining cases receiving FMT for inflammatory bowel disease. FMT had also been applied for irritable bowel syndrome, metabolic syndrome and constipation in small numbers. Adverse events appear to be uncommon, often mild and self-limiting; however, serious adverse events including bacteraemia, perforations and death have been reported.

CONCLUSION

The vast majority of adverse events of FMT appear to be mild, self-limiting and gastrointestinal in nature. In some cases, a credible association was not established due to the lack of controlled data. There is a need for standardized, randomized controlled trials to qualify and quantify the risks associated with FMT.

Fecal Microbiota Transplant: Respice, Adspice, Prospice

Respice, Adspice, Prospice, look to the past, look to the present, look to the future, is one of life's valuable axioms; for it is only if one knows where one has been can one intelligently prepare for the future. I have used this approach here to review fecal microbiota transplant (FMT). First used in fourth-century China to treat an assortment of gastrointestinal (GI) symptoms, today FMT is primarily used for recurrent Clostridium difficile infection (RCDI). In the future, however, it is likely that microbiotic therapy will be extended beyond treatment of RCDI. Early on, fresh feces from patient-identified donors was used and administered by several routes. FMT cure rates for RCDI remain approximately 82% and 91% when fresh stool is given by the upper GI and lower GI routes, respectively, but now we are moving in the direction of using carefully vetted volunteers whose stool is processed into a variety of formulations including lyophilized material and even capsules. It is very likely that an array of products derived from feces or based on specific microbiotic profiles and commercially prepared in a controlled environment will be available to restore eubiosis to a dysbiotic intestinal microbial community, and thereby correct a variety of GI and non-GI disorders. We are witnessing a paradigm shift in therapeutics. Previously, bacteria were thought of only as potential pathogens, whereas now we appreciate that a diverse community of bacteria is crucial to the health of the host. We are now learning that to restore such diversity once it has been interrupted can result in miraculous cure. The future of microbiotic therapy is bright.