Fecal microbiota transplantation for recurrent clostridium difficile infection

Nanotechnological interventions of the microbiome as a next-generation antimicrobial therapy

The rise of antimicrobial resistance (AMR) impacts public health due to the diminished potency of existing antibiotics. The microbiome plays an important role in the host's immune system activity and shows the history of exposure to antimicrobials and its manipulation in combating antimicrobial resistance. Advancements in gene technologies, DNA sequencing, and computational biology have emerged as powerful platforms to better understand the relationship between animals and microorganisms (MOs). The past few years have witnessed an increase in the use of nanotechnology, both in industry and in academia, as tools to tackle antimicrobial resistance. New strategies of microbiome manipulation have been developed, such as the use of prebiotics, probiotics, peptides, antibodies, an appropriate diet, phage therapy, and the use of various nanotechnological techniques. Owing to the research outcomes, targeted delivery of antimicrobials with some modifications with nanoparticles can lead to the destruction of resistant microbial cells. In addition, nanoparticles have been studied for their potential antimicrobial effects both in vitro and in vivo. In this review, we highlight key opportunistic areas for applying nanotechnologies with the aim of manipulating the microbiome for the treatment of antimicrobial resistance. Besides providing a detailed review on various nanomaterials, technologies, opportunities, technical needs, and potential approaches for the manipulation of the microbiome to address these challenges, we discuss future challenges and our perspective.

<i>Helicobacter pylori</i>. The survival strategy of a commensal symbiont in the <i>Homo sapiens</i> population

Несмотря на крайне высокую степень инфицированности Helicobacter pylori в популяции Homo sapiens, подавляющее большинство инфицированных являются бессимптомными носителями. Широкое распространение инфекции H. pylori среди лиц без признаков патологии и низкая заболеваемость при хронической колонизации слизистой оболочки желудка указывают на то, что H. pylori с большей вероятностью является условно-патогенным микроорганизмом или патобионтом. Популяционная ликвидация инфекции H. pylori существенно снизила заболеваемость инфекцией H. pylori, однако появление устойчивости к противомикробным препаратам привело к их неэффективности.

Cancer and immunotherapy: a role for microbiota composition

Human microbiota plays a key role in preserving homeostasis; therefore, alteration in its composition is associated with susceptibility to various diseases. Recent findings suggest that gut microbiota may influence response to cancer treatment, especially immune checkpoint blockers (ICBs). The development of ICBs has changed outcomes of patients with cancer and has allowed sustained recovery. Unfortunately, some patients do not respond to ICBs, and microbiota may be a promising new biomarker to identify patients who will have benefit from ICBs. This review presents relationship between microbiome composition or microbiota-derived metabolites and response to ICBs or immune-related adverse events. Furthermore, we will present different strategies to modulate microbiota composition in patients to enhance ICB efficacy or dampen their toxicities which could lead to the emergence of interesting complementary treatments.

Fecal microbiota transplantation from warthog to pig confirms the influence of the gut microbiota on African swine fever susceptibility

African swine fever virus (ASFV) is the causative agent of a devastating hemorrhagic disease (ASF) that affects both domestic pigs and wild boars. Conversely, ASFV circulates in a subclinical manner in African wild pigs, including warthogs, the natural reservoir for ASFV. Together with genetic differences, other factors might be involved in the differential susceptibility to ASF observed among Eurasian suids (Sus scrofa) and African warthogs (Phacochoerus africanus). Preliminary evidence obtained in our laboratory and others, seems to confirm the effect that environmental factors might have on ASF infection. Thus, domestic pigs raised in specific pathogen-free (SPF) facilities were extremely susceptible to highly attenuated ASFV strains that were innocuous to genetically identical domestic pigs grown on conventional farms. Since gut microbiota plays important roles in maintaining intestinal homeostasis, regulating immune system maturation and the functionality of the innate/adaptive immune responses, we decided to examine whether warthog fecal microbiota transplantation (FMT) to domestic pigs affects host susceptibility to ASFV. The present work demonstrates that warthog FMT is not harmful for domestic weaned piglets, while it modifies their gut microbiota; and that FMT from warthogs to pigs confers partial protection against attenuated ASFV strains. Future work is needed to elucidate the protective mechanisms exerted by warthog FMT.

Comparison of polysaccharide glycoconjugates as candidate vaccines to combat Clostridiodes (Clostridium) difficile

Two known Clostridiodes (Clostridium) difficile surface antigens, a lipoteichoic acid (LTA) and a polysaccharide (PS-II) were isolated and purified in order to prepare glycoconjugate vaccines to the carrier protein human serum albumin utilising a reductive amination strategy. Mice and rabbits were immunized with a prime and two boost strategy and the resulting sera were examined for their ability to recognise the purified homologous antigens and subsequently killed whole cells of C. difficile strains and other Clostridia species. Immunisation derived antisera from rabbits and mice, recognised all strains of C. difficile vegetative cells examined, with generally similar titers from animals that received the LTA or the PS-II conjugates. Sera raised to the LTA conjugates were able to recognise other Clostridia species C. butyricum, C. bifermentans and C. subterminale whereas sera raised to the PS-II conjugates were not. These LTA and PS-II sera recognised live cells in an immunofluorescence assay and were also able to recognise the spore form of the bacterium. This study has confirmed that the LTA and PS-II polysaccharides are both highly conserved surface polymers of C. difficile that are easily accessible to the immune system and as such may have potential as vaccine antigens or as targets for therapeutics to combat C. difficile infection.

Fecal microbiota transplantation in gastrointestinal and extraintestinal disorders

Fecal microbiota transplantation (FMT) is the infusion of feces from a healthy donor into the gut of a recipient to treat a dysbiosis-related disease. FMT has been proven to be a safe and effective treatment for Clostridioides difficile infection, but increasing evidence supports the role of FMT in other gastrointestinal and extraintestinal diseases. The aim of this review is to paint the landscape of current evidence of FMT in different fields of application (including irritable bowel syndrome, inflammatory bowel disease, liver disorders, decolonization of multidrug-resistant bacteria, metabolic disorders and neurological disorders), as well as to discuss the current regulatory scenario of FMT, and hypothesize future directions of FMT.

Michael F, Aubry A, Henry KA, Rossotti MA, Logan SM, Hussack G, Gisch N, Hogendorf WFJ, Pedersen CM, Cox AD. Development and Characterization of Mouse Monoclonal Antibodies Specific for Clostridiodes (Clostridium) difficile Lipoteichoic Acid

Clostridiodes (Clostridium) difficile is an anaerobic Gram-positive, spore-forming nosocomial, gastrointestinal pathogen causing C. difficile-associated disease with symptoms ranging from mild cases of antibiotic-associated diarrhea to fatal pseudomembranous colitis. We developed murine monoclonal antibodies (mAbs) specific for a conserved cell surface antigen, lipoteichoic acid (LTA)of C. difficile. The mAbs were characterized in terms of their thermal stability, solubility, and their binding to LTA by surface plasmon resonance and competitive ELISA. Synthetic LTA molecules were prepared in order to better define the minimum epitope required to mimic the natural antigen, and three repeat units of the polymer were required for optimal recognition. One of the murine mAbs was chimerized with human constant region domains and was found to recognize the target antigen identically to the mouse version. These mAbs may be useful as therapeutics (standalone, in conjunction with known antitoxin approaches, or as delivery vehicles for antibody drug conjugates targeting the bacterium), as diagnostic agents, and in infection control applications.

Efficacy of Fecal Microbiota Transplantation for Clostridium difficile Infection in Children

BACKGROUND & AIMS

Fecal microbiota transplantation (FMT) is commonly used to treat Clostridium difficile infection (CDI). CDI is an increasing cause of diarrheal illness in pediatric patients, but the effects of FMT have not been well studied in children. We performed a multi-center retrospective cohort study of pediatric and young adult patients to evaluate the efficacy, safety, and factors associated with a successful FMT for the treatment of CDI.

METHODS

We performed a retrospective study of 372 patients, 11 months to 23 years old, who underwent FMT at 18 pediatric centers, from February 1, 2004, to February 28, 2017; 2-month outcome data were available from 335 patients. Successful FMT was defined as no recurrence of CDI in the 2 months following FMT. We performed stepwise logistic regression to identify factors associated with successful FMT.

RESULTS

Of 335 patients who underwent FMT and were followed for 2 months or more, 271 (81%) had a successful outcome following a single FMT and 86.6% had a successful outcome following a first or repeated FMT. Patients who received FMT with fresh donor stool (odds ratio [OR], 2.66; 95% CI, 1.39-5.08), underwent FMT via colonoscopy (OR, 2.41; 95% CI, 1.26-4.61), did not have a feeding tube (OR, 2.08; 95% CI, 1.05-4.11), or had 1 less episode of CDI before FMT (OR, 1.20; 95% CI, 1.04-1.39) had increased odds for successful FMT. Seventeen patients (4.7%) had a severe adverse event during the 3-month follow-up period, including 10 hospitalizations.

CONCLUSIONS

Based on the findings from a large multi-center retrospective cohort, FMT is effective and safe for the treatment of CDI in children and young adults. Further studies are required to optimize the timing and method of FMT for pediatric patients-factors associated with success differ from those of adult patients.

Fecal microbiota transplantation for refractory diarrhea in immunocompromised diseases: a pediatric case report

Background

Immunocompromised (IC) patients have an increased risk of refractory diarrhea. Fecal microbiota transplantation (FMT) is a safe and effective therapy for infection-related diarrhea which are mainly mediated by the loss of the microbial colonization, although there is concern that IC patients may be at higher risk of infectious complications related to FMT. And reports of FMT in IC children are limited.

Case presentation

We describe two cases of FMT in IC children with refractory diarrhea. One IC child had polyendocrinopathy, enteropathy, X-linked syndrome and the other child had graft-versus-host disease. Both of the children had a long course of diarrhea and no response to traditional treatment. FMT was performed on both patients via nasojejunal tubes under guidance of gastroduodenoscopy. After FMT, the patients achieved remission of symptoms and neither of them had related infectious complications. Microbiota analysis showed that FMT resulted in reconstruction of a diverse microbiota.

Conclusions

Use of FMT is safe and effective in treatment of refractory diarrhea in IC children with a damaged microbiota.

Ecological interventions to prevent and manage zoonotic pathogen spillover

Spillover of a pathogen from a wildlife reservoir into a human or livestock host requires the pathogen to overcome a hierarchical series of barriers. Interventions aimed at one or more of these barriers may be able to prevent the occurrence of spillover. Here, we demonstrate how interventions that target the ecological context in which spillover occurs (i.e. ecological interventions) can complement conventional approaches like vaccination, treatment, disinfection and chemical control. Accelerating spillover owing to environmental change requires effective, affordable, durable and scalable solutions that fully harness the complex processes involved in cross-species pathogen spillover.

This article is part of the theme issue ‘Dynamic and integrative approaches to understanding pathogen spillover’.

Microbiota and Phage Therapy: Future Challenges in Medicine

An imbalance of bacterial quantity and quality of gut microbiota has been linked to several pathologies. New strategies of microbiota manipulation have been developed such as fecal microbiota transplantation (FMT); the use of pre/probiotics; an appropriate diet; and phage therapy. The presence of bacteriophages has been largely underestimated and their presence is a relevant component for the microbiome equilibrium. As a promising treatment, phage therapy has been extensively used in Eastern Europe to reduce pathogenic bacteria and has arisen as a new method to modulate microbiota diversity. Phages have been selected and “trained” to infect a wide spectrum of bacteria or tailored to infect specific antibiotic resistant bacteria present in patients. The new development of genetically modified phages may be an efficient tool to treat the gut microbiota dysbiosis associated with different pathologies and increased production of bacterial metabolites and subsequently decrease systemic low-grade chronic inflammation associated with chronic diseases. Microbiota quality and mitochondria dynamics can be remodulated and manipulated by phages to restore the equilibrium and homeostasis of the system. Our aim is to highlight the great interest for phages not only to eliminate and control pathogenic bacterial infection but also in the near future to modulate the microbiota by adding new functions to selected bacteria species and rebalance the dynamic among phages and bacteria. The challenge for the medicine of tomorrow is to re-think and redesign strategies differently and far from our traditional thinking.

Fecal microbiota transplantation: a promising strategy in preventing the progression of non-alcoholic steatohepatitis and improving the anti-cancer immune response

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) has the potential to progress to hepatocellular carcinoma (HCC). However, limited therapies are currently available for the treatment of advanced HCC, and one must strive to search for novel strategies.

AREAS COVERED

We provide insight on current knowledge related to gut microbiota and NAFLD, summarize the sequence linking obesity to HCC and highlight gut dysbiosis in obesity and its consequences on the liver. We detail the impact of the gut microbiota on immune checkpoint inhibitors, and speculate on the role of fecal microbiota transplantation (FMT) in NAFLD and in improving anti-neoplastic immune response.

EXPERT OPINION

Manipulation of the gut microbiota seems promising in the secondary prevention of NAFLD/NASH and/or in potentiating anti-cancer immune response, notably by a global 'resetting' using FMT. However, the composition of a 'harmful' gut microbiome in HCC still needs to be characterized, and the impact of FMT on HCC growth needs to be assessed.

Efficacy of faecal microbiota transplantation for treating acute colitis in horses undergoing colic surgery

ABSTRACT: The report describes the outcome of four horses treated with homologous faecal microbiota transplantation (FMT) for acute colitis. The horses developed diarrhoea and fever a few days after a laparotomy to treat gastrointestinal disease. Medical records were reviewed to identify the horses as well as to describe the primary intestinal disease, clinical findings, surgical intervention, FMT protocol, outcome and follow-up of each case. The principle of the efficacy of FMT is that restoration of a balanced nonpathogenic bacterial population may be the primary defence mechanism against colonization of pathogenic bacteria in the equine gastrointestinal tract. The FMT did not produce adverse reactions and was demonstrated to rapidly control diarrhoea and fever in all cases. A complete resolution of clinical sings was observed within 24 hours when horses were given a single FMT. Further clinical studies are necessary to determine the optimal preparation and to reinforce the efficacy of FMT for treating acute colitis following colic surgery. The technique has the potential to be an inexpensive, safe and highly efficient tool for the prevention and treatment of infectious gastrointestinal diseases in horses, preventing antimicrobial resistance.

Fecal microbiota transplantation in recurrent Clostridium difficile infection: the first prospective study of 30 patients in Romania

Introduction: The infection with Clostridium difficile has increased in incidence worldwide and it raises many problems with regard to therapy, resistance to treatment and especially recurrence. Recurrence is frequent in patients treated for Clostridium difficile infection, requiring vancomycin by mouth, with limited alternatives. The literature shows that one of the most efficient treatment methods in Clostridium difficile infection is the transplantation of gut microbiota, also known as fecal microbiota transplantation. Aim: We present our results following FMT performed in patients with recurrent Clostridium difficile infection, and propose a simple and effective protocol for fecal microbiota transplantation. Study design: The study was prospective. The phases of the FMT procedure: assessment of patient eligibility, patient’s consent, identification and screening of donors, discontinuation of antibiotics (vancomycin, metronidazole) 3 days prior to the procedure. Methods: Between 2013 and 2015, FMT was performed in 30 patients with recurrent Clostridium difficile infection, by direct infusion of extensively processed donor fecal matter via colonoscopy. We followed up the patients for 12 months. Results: Immediate post-transplantation outcome in what concerns stool frequency during the follow-up period (7 days) was encouraging in 93.33% of patients. The donors were healthy individuals (53% 1st degree relatives), previously screened for possible infections and infestations. This result was sustained at 6-month and 12-month follow-up. Post-transplantation recurrence occurred in 6.67% (2 patients), which responded well to treatment and did not require a new vancomycin course. Conclusions: Fecal microbiota transplantation via colonoscopy is effective, safe, easy to perform, it yields lasting results and is therefore a good option for recurrent or treatment-resistant Clostridium difficile infection.

Successful Fecal Microbiota Transplantation in a Patient with Severe Complicated Clostridium difficile Infection after Liver Transplantation

Clostridium difficile infection (CDI) represents one of the most common healthcare-associated infections. Due to increasing numbers of recurrences and therapy failures, CDI has become a major disease burden. Studies have shown that fecal microbiota transplantation (FMT) can both be a safe and highly efficacious therapy for patients with therapy-refractory CDI. However, patients undergoing solid organ transplantation are at high risk for CDI due to long-term immunosuppression, previous antibiotic therapy, and proton pump inhibitor use. Additionally, these patients may be especially prone to adverse events related to FMT. Here, we report a successful FMT in a patient with severe therapy-refractory CDI after liver transplantation.

Fecal microbiota transplantation for recurrent clostridium difficile infection in children

Fecal microbiota transplantation (FMT) is a relatively simple, promising treatment for recurrent Clostridium difficile infection. While there are a wide variety of approaches including mode of delivery, the results are nonetheless encouraging, even amongst younger children. Experience with FMT in the pediatric population is increasing, showing similar success compared to adults. This article will provide an overview of C. difficile infection along with review of the rationale, methods and complications of FMT including the current experience of FMT in children.

Microbiome and Gut Dysbiosis

The gastrointestinal (GI) tract is the residence of trillions of microorganisms that include bacteria, archaea, fungi and viruses. The collective genomes of whole microbial communities (microbiota) integrate the gut microbiome. Up to 100 genera and 1000 distinct bacterial species were identified in digestive tube niches. Gut microbiomes exert permanent pivotal functions by promoting food digestion, xenobiotic metabolism and regulation of innate and adaptive immunological processes. Proteins, peptides and metabolites released locally and at distant sites trigger many cell signalling and pathways. This intense crosstalk maintains the host-microbial homeostasis. Diet, age, diet, stress and diseases cause increases or decreases in relative abundance and diversity bacterial specie of GI and other body sites. Studies in animal models and humans have shown that a persistent imbalance of gut's microbial community, named dysbiosis, relates to inflammatory bowel diseases (IBD), irritable bowel syndrome (IBS), diabetes, obesity, cancer, cardiovascular and central nervous system disorders. Notably specific bacterial communities are promising clinical target to treat inflammatory and infectious diseases. In this context, intestinal microbiota transplantation (IMT) is one optional treatment for IBD, in particular to patients with recurrent Clostridium difficile-induced pseudo-membrane colitis. Here we discuss on recent discoveries linking whole gut microbiome dysbiosis to metabolic and inflammatory diseases and potential prophylactic and therapeutic applications of faecal and phage therapy, probiotic and prebiotic diets.

Interaction of gut microbiota with bile acid metabolism and its influence on disease states

Primary bile acids serve important roles in cholesterol metabolism, lipid digestion, host-microbe interactions, and regulatory pathways in the human host. While most bile acids are reabsorbed and recycled via enterohepatic cycling, ∼5% serve as substrates for bacterial biotransformation in the colon. Enzymes involved in various transformations have been characterized from cultured gut bacteria and reveal taxa-specific distribution. More recently, bioinformatic approaches have revealed greater diversity in isoforms of these enzymes, and the microbial species in which they are found. Thus, the functional roles played by the bile acid-transforming gut microbiota and the distribution of resulting secondary bile acids, in the bile acid pool, may be profoundly affected by microbial community structure and function. Bile acids and the composition of the bile acid pool have historically been hypothesized to be associated with several disease states, including recurrent Clostridium difficile infection, inflammatory bowel diseases, metabolic syndrome, and several cancers. Recently, however, emphasis has been placed on how microbial communities in the dysbiotic gut may alter the bile acid pool to potentially cause or mitigate disease onset. This review highlights the current understanding of the interactions between the gut microbial community, bile acid biotransformation, and disease states, and addresses future directions to better understand these complex associations.

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.

Recommendations for Probiotic Use--2015 Update: Proceedings and Consensus Opinion

This paper describes the consensus opinion of the participants in the 4th Triennial Yale/Harvard Workshop on Probiotic Recommendations. The recommendations update those of the first 3 meetings that were published in 2006, 2008, and 2011. Recommendations for the use of probiotics in necrotizing enterocolitis, childhood diarrhea, inflammatory bowel disease, irritable bowel syndrome and Clostridium difficile diarrhea are reviewed. In addition, we have added recommendations for liver disease for the first time. As in previous publications, the recommendations are given as A, B, or C ratings.

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.

Human microbiomes and their roles in dysbiosis, common diseases, and novel therapeutic approaches

The human body is the residence of a large number of commensal (non-pathogenic) and pathogenic microbial species that have co-evolved with the human genome, adaptive immune system, and diet. With recent advances in DNA-based technologies, we initiated the exploration of bacterial gene functions and their role in human health. The main goal of the human microbiome project is to characterize the abundance, diversity and functionality of the genes present in all microorganisms that permanently live in different sites of the human body. The gut microbiota expresses over 3.3 million bacterial genes, while the human genome expresses only 20 thousand genes. Microbe gene-products exert pivotal functions via the regulation of food digestion and immune system development. Studies are confirming that manipulation of non-pathogenic bacterial strains in the host can stimulate the recovery of the immune response to pathogenic bacteria causing diseases. Different approaches, including the use of nutraceutics (prebiotics and probiotics) as well as phages engineered with CRISPR/Cas systems and quorum sensing systems have been developed as new therapies for controlling dysbiosis (alterations in microbial community) and common diseases (e.g., diabetes and obesity). The designing and production of pharmaceuticals based on our own body’s microbiome is an emerging field and is rapidly growing to be fully explored in the near future. This review provides an outlook on recent findings on the human microbiomes, their impact on health and diseases, and on the development of targeted therapies.

Impact of fluoroquinolones on human microbiota. Focus on the emergence of antibiotic resistance

The aggregate of microorganisms residing on the surface of the skin, in the oropharynx and in the GI tract, known as the human microbiota, play a major role as natural reservoirs for bacterial resistance to antibiotics. Fluoroquinolones (FQ) are among the most prescribed antibiotics and a major increase in FQ resistance is occurring worldwide. High concentrations of FQ are found in microbial ecosystems explaining their profound effect on the clinically relevant bacteria that compose them. Yet, because of different local pharmacokinetics, distinct selective pressures occur in the different microbiota. Here we review the qualitative and quantitative impact of FQ on the three main human microbiota and their consequences, particularly in terms of emergence of antibiotic resistance. Finally, we review potential actions that could decrease the impact of FQs on microbiota.

Harnessing regulatory T cells for the treatment of inflammatory bowel disease

Regulatory CD4 T (Treg) cells are comprised of a heterogeneous population of cells that play a vital role in suppressing inflammation and maintaining immune tolerance. The immunoregulatory function of Treg cells is especially important in the intestine where the mucosa is exposed to a diverse array of foreign antigens-including those derived from food and commensal bacteria. Treg cells are enriched in the intestinal lamina propria and provide a crucial function in promoting tolerance to enteric antigens while modulating tissue inflammation. Correspondingly, Treg cell dysfunction is associated with a breakdown in intestinal tolerance and the induction of aberrant immune responses that may contribute to the pathogenesis of inflammatory bowel disease. This review will provide a brief overview of Treg cell biology with a focus on Foxp3 Treg and type 1 regulatory (Tr1) cells and summarize the evidence for defective Treg cells in experimental and human inflammatory bowel disease. The potential application of Treg cells as a treatment for inflammatory bowel disease will also be discussed in the context of Treg infusion therapy and the in vivo induction/expansion of intestinal Treg cells.

Norovirus in healthcare settings

Purpose of review

To provide an overview of the burden of norovirus disease in healthcare settings and the factors responsible for outbreaks in these institutions; to assess progress on interventions aimed at reducing the burden of norovirus disease.

Recent findings

Norovirus outbreaks in healthcare settings are driven by confluence of viral diversity, the built environment, and host factors. Some of these characteristics may be modifiable and the target of successful interventions.

Summary

Most norovirus outbreaks in hospital and residential care institutions are associated with a particular genotype, known as GII.4. The persistence of norovirus is associated with strain diversity, which is driven by immune evasion and viral adaptation to interaction with a variety of human histo-blood group antigens. The healthcare environment presents serious challenges for control, both because of the physical structure of the built space and the high levels of contact among patient populations who may have compromised hygiene. Increased vulnerability among the populations in healthcare institutions is likely to be multifactorial and may include the following: nutritional status, immunodeficiency or senescence, chronic inflammation, and microbiome alterations. Current control measures are based on general infection control principles, and treatment is mainly supportive and nonspecific. Vaccines and antiviral agents are being developed with promising results, but none are currently available.

Manipulating the gut microbiota to maintain health and treat disease

BACKGROUND

The intestinal microbiota composition varies between healthy and diseased individuals for numerous diseases. Although any cause or effect relationship between the alterations in the gut microbiota and disease is not always clear, targeting the intestinal microbiota might offer new possibilities for prevention and/or treatment of disease.

OBJECTIVE

Here we review some examples of manipulating the intestinal microbiota by prebiotics, probiotics, and fecal microbial transplants.

RESULTS

Prebiotics are best known for their ability to increase the number of bifidobacteria. However, specific prebiotics could potentially also stimulate other species they can also stimulate other species associated with health, like Akkermansia muciniphila, Ruminococcus bromii, the Roseburia/Enterococcus rectale group, and Faecalibacterium prausnitzii. Probiotics have beneficial health effects for different diseases and digestive symptoms. These effects can be due to the direct effect of the probiotic bacterium or its products itself, as well as effects of the probiotic on the resident microbiota. Probiotics can influence the microbiota composition as well as the activity of the resident microbiota. Fecal microbial transplants are a drastic intervention in the gut microbiota, aiming for total replacement of one microbiota by another. With numerous successful studies related to antibiotic-associated diarrhea and Clostridium difficile infection, the potential of fecal microbial transplants to treat other diseases like inflammatory bowel disease, irritable bowel syndrome, and metabolic and cardiovascular disorders is under investigation.

CONCLUSIONS

Improved knowledge on the specific role of gut microbiota in prevention and treatment of disease will help more targeted manipulation of the intestinal microbiota. Further studies are necessary to see the (long term) effects for health of these interventions.

Simple faecal preparation and efficacy of frozen inoculum in faecal microbiota transplantation for recurrent Clostridium difficile infection--an observational cohort study

BACKGROUND

Faecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection (rCDI). The finding of suitable donor, donor screening and preparation of faecal transplants are challenging in clinical work.

AIM

To develop a practical protocol for preparing frozen transplants and to compare the efficacy of previously frozen and fresh faeces in treating rCDI.

METHODS

Two healthy volunteers acted as universal donors for the frozen faecal preparations, which were prepared by suspending faeces into physiological saline, adding glycerol to a final concentration of 10% and storing at -80 °C. We compared the outcomes of patients with rCDI who had undergone FMT at colonoscopy and received infusion of previously prepared, freeze-stored faeces (n = 23) or fresh faeces from individual (n = 15) or universal donors (n = 11) (total n = 49). Clinical failure was defined as persistent or recurrent symptoms with a positive C. difficile toxin stool test, and a need for new therapy.

RESULTS

At 12 weeks post-FMT, symptoms were resolved in 22 of 23 patients receiving previously frozen faeces, and in all 11 or 14 of 15 patients receiving fresh faeces from the universal or individual donors respectively (totally 25 of 26; P = ns, success rate 96%). Mild transient fever appeared for two patients receiving frozen faeces, but no other significant side effects were observed. 42 patients were followed up for a year post-FMT and the success rate was 88% in both fresh and frozen faeces groups.

CONCLUSIONS

Preparation of frozen transplants simplifies the practical aspects of faecal microbiota transplantation without loss of efficacy or safety.

Hormones and antibiotics in nature: a laboratory module designed to broaden undergraduate perspectives on typically human-centered topics

Bringing discovery-based research into undergraduate laboratory courses increases student motivation and learning gains over traditional exercises that merely teach technique or demonstrate well-documented phenomena. Laboratory experiences are further enhanced when they are designed to challenge student perspectives on topics relevant to their lives. To this end, a laboratory module on antibiotics and hormones, which are generally discussed in the context of human health, was developed for students to explore the multifaceted roles of antibiotics and hormones in nature (e.g. interspecies communication) via reading primary scientific literature and performing discovery-based experiments. The main objective of this module was to increase the general biological literacy of students as determined by their ability to connect the Five Core Concepts of Biological Literacy (American Association for the Advancement of Science, Vision and Change in Undergraduate Education: A Call to Action, 2011) to the topics "hormones" and "antibiotics" in pre- and postmodule surveys. After discussing unpublished research findings, cell biology students performed experiments demonstrating that: 1) fungi may promote fern growth via hormone production, 2) novel bacterial isolates in the genus Streptomyces produce antifungal compounds, and 3) subinhibitory antibiotic concentrations may enhance soil bacterial growth. The third finding provided evidence supporting a hypothesis framed in a scientific article that students read and discussed. Student perspectives on premodule surveys focused on roles of hormones and antibiotics in the human body (e.g. development, fighting infection), but their broadened postmodule perspectives encompassed the roles of these molecules in organismal communication and possibly the evolution of multicellularity.

Fecal microbiota transplantation: a new old kid on the block for the management of gut microbiota-related disease

Gut microbiota is deeply involved in the regulation of both health and disease within our body. The restoration of a healthy gut microbiota is, therefore, a main clinical target in the management of diseases associated with its disruption. Fecal microbiota transplantation (FMT) is an old therapy that has recently been rediscovered, having proved a clear efficacy against recurrent Clostridium difficile infection. By restoring the altered gut microbiota in a substantial and durable manner, FMT is considered a cutting-edge promising option for the treatment of disease that recognize the alteration of the gut microbiota as having a pathogenic role. FMT has shown interesting (even if uncertain) results in diseases such as metabolic syndrome and inflammatory bowel diseases. Moreover, the definition of a standard procedural protocol for each specific disease, as well as exhaustive studies about the relationship between donor's microbiota composition and clinical results, will certainly improve the therapeutic potential of FMT. Both the application of cutting-edge technologies for the assessment of gut microbiota composition (such as metagenomics) and the development of well-designed, large randomized trials are needed to put such perspectives into practice.

Fecal microbiota transplantation in children with recurrent Clostridium difficile infection

Clostridium difficile eradication using fecal microbiota transplantation (FMT) has been successful in adults but little information is available in pediatrics. We report 6 pediatric patients with refractory C. difficile cured by FMT with no recurrences to date. Our results demonstrate that FMT can be an effective treatment for refractory C. difficile infection in pediatrics. Long-term safety and efficacy need to be studied.

Recommendations for probiotic use in humans-a 2014 update

Probiotics have gained worldwide use during the last two decades. However, which probiotic to use in which clinical condition has remained confusing in some clinical conditions. We convened a workshop at Yale in conjunction with Harvard in 2005, inviting a spectrum of probiotic authorities to discuss and reach conclusions on recommendations for use in common clinical conditions; the workshop was reconvened again in 2008 and in 2011. Each time the group of authorities was enlarged and varied depending on research studies. This article lists the recommendations updated from 2011 and is amended to bring it up to date in childhood and adult diarrhea, antibiotic-associated diarrhea, necrotizing enterocolitis, inflammatory bowel disorders, irritable bowel syndrome, allergic disorders, and radiation enteritis pending our 4th Triennial Yale/Harvard workshop to be convened in 2015.

European Society of Clinical Microbiology and Infectious Diseases: update of the treatment guidance document for Clostridium difficile infection

In 2009 the first European Society of Clinical Microbiology and Infection (ESCMID) treatment guidance document for Clostridium difficile infection (CDI) was published. The guideline has been applied widely in clinical practice. In this document an update and review on the comparative effectiveness of the currently available treatment modalities of CDI is given, thereby providing evidence-based recommendations on this issue. A computerized literature search was carried out to investigate randomized and non-randomized trials investigating the effect of an intervention on the clinical outcome of CDI. The Grades of Recommendation Assessment, Development and Evaluation (GRADE) system was used to grade the strength of our recommendations and the quality of the evidence. The ESCMID and an international team of experts from 11 European countries supported the process. To improve clinical guidance in the treatment of CDI, recommendations are specified for various patient groups, e.g. initial non-severe disease, severe CDI, first recurrence or risk for recurrent disease, multiple recurrences and treatment of CDI when oral administration is not possible. Treatment options that are reviewed include: antibiotics, toxin-binding resins and polymers, immunotherapy, probiotics, and faecal or bacterial intestinal transplantation. Except for very mild CDI that is clearly induced by antibiotic usage antibiotic treatment is advised. The main antibiotics that are recommended are metronidazole, vancomycin and fidaxomicin. Faecal transplantation is strongly recommended for multiple recurrent CDI. In case of perforation of the colon and/or systemic inflammation and deteriorating clinical condition despite antibiotic therapy, total abdominal colectomy or diverting loop ileostomy combined with colonic lavage is recommended.

Fecal microbial therapy: promises and pitfalls

A rapidly expanding range of diverse human diseases is now associated with perturbations to the gastrointestinal microbiome. Fecal microbial transplant (FMT) has been used with high rates of efficacy to treat gastrointestinal microbiome perturbation associated with recurrent Clostridium difficile infection, and is now being considered for other indications. Here we discuss the gut microbiome, review published and ongoing studies using FMT as a treatment modality for human disease, consider the regulatory aspects of FMT, and outline some factors that should be considered in patients in whom this therapeutic strategy is being contemplated.

Staggered and tapered antibiotic withdrawal with administration of kefir for recurrent Clostridium difficile infection

Daily administration of the probiotic kefir given in combination with a staggered and tapered antibiotic withdrawal regimen may resolve recurrent Clostridium difficile infection as effectively as fecal microbiota transplantation.

Gut microbiota modulation: probiotics, antibiotics or fecal microbiota transplantation?

Gut microbiota is known to have a relevant role in our health, and is also related to both gastrointestinal and extradigestive diseases. Therefore, restoring the alteration of gut microbiota represents an outstanding clinical target for the treatment of gut microbiota-related diseases. The modulation of gut microbiota is perhaps an ancestral, innate concept for human beings. At this time, the restoration of gut microbiota impairment is a well-established concept in mainstream medicine, and several therapeutic approaches have been developed in this regard. Antibiotics, prebiotics and probiotics are the best known and commercially available options to overcome gastrointestinal dysbiosis. Fecal microbiota transplantation is an old procedure that has recently become popular again. It has shown a clear effectiveness in the treatment of C. difficile infection, and now represents a cutting-edge option for the restoration of gut microbiota. Nevertheless, such weapons should be used with caution. Antibiotics can indeed harm and alter gut microbiota composition. Probiotics, instead, are not at all the same thing, and thinking in terms of different strains is probably the only way to improve clinical outcomes. Moreover, fecal microbiota transplantation has shown promising results, but stronger proofs are needed. Considerable efforts are needed to increase our knowledge in the field of gut microbiota, especially with regard to the future use in its modulation for therapeutic purposes.

Fecal transplant for recurrent Clostridium difficile infection in children with and without inflammatory bowel disease

Ten children at our institution received single-infusion fecal microbiome transplant (FMT) using healthy, related screened donor stool to treat recurrent Clostridium difficile infection (RCDI) via nasogastric tube (2 patients) or colonoscopic delivery. Nine of the 10 (90%) children had resolution of their symptoms after a single-infusion FMT with follow-up of 1 month to 4 years. No concerning related adverse events were recognized during short- or long-term follow-up. Three of these children had concomitant inflammatory bowel disease and 2 of these 3 (66%) patients cleared RCDI with no clinical change in their underlying inflammatory bowel disease clinical activity as assessed by Physician's Global Assessment. All of the patients who had clinical improvement of gastrointestinal symptoms of RCDI while treated with antibiotics had lasting return of baseline health after FMT.

Fecal microbiota transplant for relapsing Clostridium difficile infection using a frozen inoculum from unrelated donors: a randomized, open-label, controlled pilot study

BACKGROUND

Recurrent Clostridium difficile infection (CDI) with poor response to standard antimicrobial therapy is a growing medical concern. We aimed to investigate the outcomes of fecal microbiota transplant (FMT) for relapsing CDI using a frozen suspension from unrelated donors, comparing colonoscopic and nasogastric tube (NGT) administration.

METHODS

Healthy volunteer donors were screened and a frozen fecal suspension was generated. Patients with relapsing/refractory CDI were randomized to receive an infusion of donor stools by colonoscopy or NGT. The primary endpoint was clinical resolution of diarrhea without relapse after 8 weeks. The secondary endpoint was self-reported health score using standardized questionnaires.

RESULTS

A total of 20 patients were enrolled, 10 in each treatment arm. Patients had a median of 4 (range, 2-16) relapses prior to study enrollment, with 5 (range, 3-15) antibiotic treatment failures. Resolution of diarrhea was achieved in 14 patients (70%) after a single FMT (8 of 10 in the colonoscopy group and 6 of 10 in the NGT group). Five patients were retreated, with 4 obtaining cure, resulting in an overall cure rate of 90%. Daily number of bowel movements changed from a median of 7 (interquartile range [IQR], 5-10) the day prior to FMT to 2 (IQR, 1-2) after the infusion. Self-ranked health score improved significantly, from a median of 4 (IQR, 2-6) before transplant to 8 (IQR, 5-9) after transplant. No serious or unexpected adverse events occurred.

CONCLUSIONS

In our initial feasibility study, FMT using a frozen inoculum from unrelated donors is effective in treating relapsing CDI. NGT administration appears to be as effective as colonoscopic administration.

CLINICAL TRIALS REGISTRATION

NCT01704937.

Faecal microbiota transplantation for Clostridium difficile infection

PURPOSE

To review the current clinical literature regarding the use of fecal microbiota transplantation (FMT) for severe and recurrent Clostridium difficile disease (CDAD).

BACKGROUND

Clostridium difficile (C. difficile) is a gram positive, spore forming bacteria, and an important nosocomial pathogen causing healthcare associated diarrhoea in hospitalized patients in developed and developing countries. During the past several years, CDAD has become more frequent, severe, refractory, and more likely to relapse. It has become apparent that C. difficile is no longer just a nosocomial infection, with a rising rate of infection in populations not previously affected. Standard treatment regimens and new medications exist, but recurrence rates are high.

METHODS

Using PubMed, we conducted a Boolean search with the following medical subject headings (MeSH): Clostridium difficile infection and fecal transplantation or recurrent C. difficile infection. We restricted the search to human studies, published in English, between 2011 through June 1, 2013.

RESULTS

There were 104 publications identified. Of those related to FMT, there were 20 clinical reviews, 6 case reports, 3 clinical trials (one, a randomized control trial), and 1 meta-analysis. Since 1958 there have been 36 published reports of FMT for C. difficile infection (CDI) representing 583 patients. Success rates were higher when FMT was administered via colonoscopy (representing the majority of patients, 79.2%). The overall success rate for FMT, regardless of administration method, was 80-98%.

CONCLUSION

Fecal microbiota transplantation attempts to restore the normal microbiome of the colon, and has achieved a cure rate reaching more than 90%. Mounting evidence supports the utility of FMT for severe and recurrent cases of CDI. Barriers that will need to be addressed are patient perceptions and fears, standard protocol development, and further clinical trials.

Microbiota-liver axis in hepatic disease

Accumulating evidence indicates that the gut microbiota, long appreciated to be a key determinant of intestinal inflammation, is also playing a key role in chronic inflammatory disease of the liver. Such studies have yielded a general central hypothesis whereby microbiota products activate the innate immune system to drive proinflammatory gene expression, thus promoting chronic inflammatory disease of the liver. This article reviews the background supporting this hypothesis, outlines how it can potentially explain classic and newly emerging epidemiological chronic inflammatory liver disease, and discusses potential therapeutic means to manipulate the microbiota so as to prevent and/or treat liver disease.

Fecal transplantation: re-discovering the value of stool

PURPOSE OF REVIEW

For over 1000 years, stool in various forms has been used to treat disease. Within the past few decades, fecal infusion either rectally or via a nasogastric tube has become a viable option for the treatment of refractory Clostridium difficile infection (CDI), and, more recently, it has shown promise in treating inflammatory bowel disease (IBD) and metabolic disease. The purpose of this article is to review the use of feces as a treatment option in pediatric disease.

RECENT FINDINGS

The majority of publications detailing the use of fecal infusion as a medical treatment have been case reports. In the first randomized controlled trial of its kind, fecal infusion via nasogastric tube was shown to be beneficial in treating refractory CDI in adults. In another first of its kind, a pilot study on the use of fecal enemas to treat ulcerative colitis in pediatric patients found it to be well tolerated and effective.

SUMMARY

The infusion of feces into the intestinal tract shows great promise for treatment and modulation of a variety of intestinal and extraintestinal diseases. Defining the underlying mechanism, microbes, and metabolites that mediate this effect will lead to more directed, safer, and potentially more effective treatments.

Diagnosis and management of Clostridium difficile infection

Clostridium difficile infection (CDI) is increasing in frequency and severity in and out of the hospital, with a high probability of recurrence after treatment. The recent literature on CDI was reviewed using PubMed to include recent publications dealing with diagnosis and therapy. Real-time polymerase chain reaction is a sensitive and useful diagnostic test for CDI but there are growing concerns of false-positive test results if the rate of CDI is low in the patient population providing samples and/or if the population being studied commonly includes people with C difficile colonization. Recommended therapy of CDI includes oral metronidazole for milder cases of CDI and oral vancomycin or fidaxomicin for more severe cases, each given for 10 days. Colectomy is being performed more frequently in patients with fulminant CDI. For treatment of first recurrences the drug used in the first bout can be used again and for second recurrences longer courses of vancomycin often are given in a tapered dose or intermittently to allow gut flora reconstitution, or other treatments including fidaxomicin may be used. Bacteriotherapy with fecal transplantation is playing an increasing role in therapy of recurrent cases. Metagenomic studies of patients with CDI during successful therapy are needed to determine how best to protect the flora from assaults from antibacterial drugs and to develop optimal therapeutic approaches. Immunotherapy and immunoprophylaxis offer opportunities to prevent CDI, to speed up recovery from CDI, and to eliminate recurrent infection. Humanized monoclonal antitoxin antibodies and active immunization with vaccines against C difficile or its toxins are both in development and appear to be of potential value.

Alteration of the intestinal microbiome: fecal microbiota transplant and probiotics for Clostridium difficile and beyond

Clostridium difficile infection is increasingly common with a high risk of recurrence despite antibiotic treatment. In cases of recurrent C. difficile infection, fecal microbiota transplant (FMT) is a highly effective treatment option promoting the restoration of normal gut microbiota. Furthermore, preliminary uncontrolled evidence demonstrates possible benefit of FMT in the management of some cases of inflammatory bowel disease and chronic constipation. In addition to presenting an overview of FMT, we discuss the role of probiotics, a more common approach to modifying the intestinal microbiome. Probiotics have been utilized broadly for many disease processes, including gastrointestinal, cardiovascular and allergic disease settings, although with limited and inconsistent results. Multiple potential areas for research are also identified.