Saccharomyces cerevisiae fungemia in a neutropenic patient treated with Saccharomyces boulardii

Probiotics-related Clostridium butyricum bacteraemia after COVID-19, confirmed by whole-genome sequencing

A man in his 70s was admitted to an intensive care unit with severe COVID-19 and treated with dexamethasone and tocilizumab. After recovery from COVID-19, he developed Clostridium butyricum bacteraemia and non-occlusive mesenteric ischaemia, with fatal outcome. He had been prescribed C. butyricum MIYAIRI 588 fine granules as probiotics for a month. The genome sequences of the C. butyricum isolate from the blood culture and C. butyricum MIYAIRI 588 fine granules were identical by single nucleotide polymorphism analysis. This is the first case of definitive probiotics-related C. butyricum bacteraemia after treatment of severe COVID-19.

Saccharomyces cerevisiae fungemias: how heterogenous is their management?

Saccharomyces cerevisiae is a yeast used mainly as a probiotic for prevention or treatment of diarrhoea. However, the prevalence of S. cerevisiae fungemia has risen over the past years, notably among patients with predisposing factors. This retrospective study presents 21 cases of S. cerevisiae fungemia at the University Hospital of Liege from 2000 to 2022, their clinical relevance and therapeutic management. Each patient presented one or several risk factors prior to fungemia. The isolated strains presented high minimal inhibitory concentration for fluconazole, while MICs for amphotericin B, voriconazole and echinocandins were low. Some patients received antifungal therapy, while for others only central and peripheral lines were removed and probiotics discontinued. The MICs obtained for voriconazole and echinocandins makes them an alternative treatment to fluconazole and amphotericin B as reported in other studies. Since a S. cerevisiae fungemia can induce the same complications as candidemia, follow-up blood cultures should be collected and metastatic foci should be looked for. This study showed an important discrepancy in the clinical management of infections due to S. cerevisiae and highlights the need for guidelines.

Guideline for the management of Clostridioides difficile infection in pediatric patients with cancer and hematopoietic cell transplantation recipients: 2024 update

Our objective was to update a clinical practice guideline for the prevention and treatment of Clostridioides difficile infection (CDI) in pediatric patients with cancer and hematopoietic cell transplantation recipients. We reconvened an international multi-disciplinary panel. A systematic review of randomized controlled trials (RCTs) for the prevention or treatment of CDI in any population was updated and identified 31 new RCTs. Strong recommendations were made to use either oral metronidazole or oral vancomycin for non-severe CDI treatment, and to use either oral vancomycin or oral fidaxomicin for severe CDI. A strong recommendation that fecal microbiota transplantation should not be routinely used to treat CDI was also made. The panel made two new good practice statements to follow infection control practices including isolation in patients experiencing CDI, and to minimize systemic antibacterial administration where feasible, especially in patients who have experienced CDI.

Clostridioides difficile infection in the allogeneic hematopoietic cell transplant recipient

Clostridioides difficile (CD) is one of the most important causes of diarrhea in hospitalized patients, in particular those who undergo an allogeneic hematopoietic cell transplant (allo-HCT) and who are more at risk of developing a CD infection (CDI) due to frequent hospitalizations, iatrogenic immunosuppression, and prolonged antibiotic cycles. CDI may represent a severe condition in allo-HCT patients, increasing the length of hospitalization, influencing the intestinal microbiome with a bidirectional association with graft-versus-host disease, and leading to unfavorable outcomes, including death. The diagnosis of CDI requires the exclusion of other probable causes of diarrhea in HCT patients and is based on highly sensitive and highly specific tests to distinguish colonization from infection. In adult patients, fidaxomicin is recommended as first-line, with oral vancomycin as an alternative agent. Bezlotoxumab may be used to reduce the risk of recurrence. In pediatric patients, vancomycin and metronidazole are still suggested as first-line therapy, but fidaxomicin will probably become standard in pediatrics in the near future. Because of insufficient safety data, fecal microbiota transplantation is not routinely recommended in HCT in spite of promising results for the management of recurrences in other populations.

The emerging role of the gut mycobiome in liver diseases

In recent years, it has become clear that gut microbiota plays a major role in the human body, both in health and disease. Because of that, the gut microbiome and its impact on human well-being are getting wider and wider attention. Studies focused on the liver are not an exception. However, the majority of the analyses are concentrated on the bacterial part of the gut microbiota, while the fungi living in the human intestines are often omitted or underappreciated. This review is focused on the gut mycobiome as an important factor that should be taken into consideration regarding liver homeostasis and its perturbations. We have collected the findings in this field and we discuss their importance. We aim to emphasize the fungal compositional changes related to liver diseases and, by that, provide novel insights into the directions of liver research and gut microbiota as a therapeutic target for liver diseases.

Nutritional modulation of the gut microbiome in allogeneic hematopoietic stem cell transplantation recipients

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) represents a potentially curative strategy for many oncological and non-oncological diseases, but it is associated with marked morbidity and mortality. The disruption of gut microbiota (GM) eubiosis has been linked to major allo-HSCT complications, including infections and acute graft vs. host disease (aGvHD), and correlates with mortality. This increasing knowledge on the role of the GM in the allo-HSCT procedure has led to fascinating ideas for modulating the intestinal ecosystem in order to improve clinical outcomes. Nutritional strategies, either by changing the route of nutritional supplementation or by administering specific molecules, are increasingly being considered as cost- and risk-effective methods of modulating the GM. Nutritional support has also emerged in the past several years as a key feature in supportive care for allo-HSCT recipients, and deterioration of nutritional status is associated with decreased overall survival and higher complication rates during treatment. Herein we provide a complete overview focused on nutritional modulation of the GM in allo-HSCT recipients. We address how pre transplant diet could affect GM composition and its ability to withstand the upsetting events occurring during transplantation. We also provide a complete overview on the influence of the route of nutritional administration on the intestinal ecosystem, with a particular focus on the comparison between enteral and parenteral nutrition (PN). Moreover, as mounting evidence are showing how specific components of post-transplant diet, such as lactose, could drastically shape the GM, we will also summarize the role of prebiotic supplementation in the modulation of the intestinal flora and in allo-HSCT outcomes.

A Review of the Role of Oral Microbiome in the Development, Detection, and Management of Head and Neck Squamous Cell Cancers

The role of the microbiome in the development and propagation of head and neck squamous cell cancer (HNSCC) is largely unknown and the surrounding knowledge lags behind what has been discovered related to the microbiome and other malignancies. In this review, the authors performed a structured analysis of the available literature from several databases. The authors discuss the merits and detriments of several studies discussing the microbiome of the structures of the aerodigestive system throughout the development of HNSCC, the role of the microbiome in the development of malignancies (generally and in HNSCC) and clinical applications of the microbiome in HNSCC. Further studies will be needed to adequately describe the relationship between HNSCC and the microbiome, and to push this relationship into a space where it is clinically relevant outside of a research environment.

Rapid DNA visual detection of polymicrobial bloodstream infection using filter paper

Bloodstream infection (BSI) is a major complication in patients with cancers due to therapy-induced neutropenia and underlying conditions, which increases hospitalization time and mortality rate. Targeted and timely antimicrobial management is crucial to save the patients’ lives and reduce the social and economic burdens. Blood culture is a routine clinical diagnostic method of BSI with a long turnaround time, and generally identifies monomicrobial BSI. Thus, polymicrobial BSI often goes undetected although it occurs more frequently in these patients and results in more severe outcomes compared to monomicrobial BSI. In this work, we apply glutaric anhydride, N-hydroxysuccinimide and N,N′-dicyclohexylcarbodiimide to fabricate a functional surface on cellulose filter paper. Targeting three pathogens (Escherichia coli, Saccharomyces cerevisiae, and human cytomegalovirus) commonly occurring in BSI in neutropenic patients, we demonstrate rapid and accurate triplex pathogen DNA detection using the functionalized paper. All three pathogen DNA was identified in 1–5 min with a detection limit of 0.1–0.5 ng/µL. The developed test tool has the potential to provide rapid polymicrobial BSI diagnosis in support of timely, accurate antimicrobial treatment, and could be integrated into an automatic sample-to-result portable equipment.

The Role of Gut Bacteria and Fungi in Alcohol-Associated Liver Disease

Cirrhosis and liver cancer caused by alcohol-associated liver disease (ALD) are serious threats to people's health. In addition to hepatic cell apoptosis and liver inflammation caused by oxidative stress during alcohol metabolism, intestinal microbiota disorders are also involved in the onset and development of ALD. Ethanol and its' oxidative and non-oxidative metabolites, together with dysbiosis-caused-inflammation, destroys the intestinal barrier. Changes of several microbial metabolites, such as bile acids, short-chain fatty acids, and amino acid, are closely associated with gut dysbiosis in ALD. The alcohol-caused dysbiosis can further influence intestinal barrier-related proteins, such as mucin2, bile acid-related receptors, and aryl hydrocarbon receptor (AhR), and these abnormal changes also participate in the injury of the intestinal barrier and hepatic steatosis. Gut-derived bacteria, fungi, and their toxins, such as lipopolysaccharide (LPS) and β-glucan translocate into the liver through the damaged intestinal barrier and promote the progression of inflammation and fibrosis of ALD. Thus, the prevention of alcohol-induced disruption of intestinal permeability has a beneficial effect on ALD. Currently, multiple therapeutic treatments have been applied to restore the gut microbiota of patients with ALD. Fecal microbial transplantation, probiotics, antibiotics, and many other elements has already shown their ability of restoring the gut microbiota. Targeted approaches, such as using bacteriophages to remove cytolytic Enterococcus faecalis, and supplement with Lactobacillus, Bifidobacterium, or boulardii are also powerful therapeutic options for ALD.

Gut non-bacterial microbiota contributing to alcohol-associated liver disease

Intestinal microbiota, dominated by bacteria, plays an important role in the occurrence and the development of alcohol-associated liver disease (ALD), which is one of the most common liver diseases around the world. With sufficient studies focusing on the gut bacterial community, chronic alcohol consumption is now known as a key factor that alters the composition of gut bacterial community, increases intestinal permeability, causes intestinal dysfunction, induces bacterial translocation, and exacerbates the process of ALD via gut-liver axis. However, gut non-bacterial communities including fungi, viruses, and archaea, which may also participate in the disease, has received little attention relative to the gut bacterial community. This paper will systematically collect the latest literatures reporting non-bacterial communities in mammalian health and disease, and review their mechanisms in promoting the development of ALD including CLEC7A pathway, Candidalysin (a peptide toxin secreted by Candida albicans), metabolites, and other chemical substances secreted or regulated by gut commensal mycobiome, virome, and archaeome, hoping to bring novel insights on our current knowledge of ALD.

Invasive Infections Associated with the Use of Probiotics in Children: A Systematic Review

Although the effectiveness of probiotics has only been proven in specific conditions, their use in children is massively widespread because of their perception as harmless products. Recent evidence raises concerns about probiotics' safety, especially but not only in the paediatric population due to severe opportunistic infections after their use. This review aimed at summarising available case reports on invasive infections related to probiotics' use in children. For this purpose, we assessed three electronic databases to identify papers describing paediatric patients with documented probiotic-derived invasive infections, with no language restrictions. A total of 49 case reports from 1995 to June 2021 were identified. The infections were caused by Lactobacillus spp. (35%), Saccharomyces spp. (29%), Bifidobacterium spp. (31%), Bacillus clausii (4%), and Escherichia coli (2%). Most (80%) patients were younger than 2 years old and sepsis was the most observed condition (69.4%). All the patients except one had at least one condition facilitating the development of invasive infection, with prematurity (55%) and intravenous catheter use (51%) being the most frequent. Three (6%) children died. Given the large use of probiotics, further studies aiming at evaluating the real incidence of probiotic-associated systemic infections are warranted.

Gut Microbiome Modulation and Faecal Microbiota Transplantation Following Allogenic Hematopoietic Stem Cell Transplantation

Nowadays, allogenic hematopoietic stem cell transplantation (allo-HSCT) is a curative therapy that is mainly recommended for hematologic malignancies. However, complications (such as graft-versus-host disease, mucositis, disease relapse, and infections) associated with the HSCT procedure contribute to the development of gut microbiota imbalance, gut-barrier disruption, and increased intestinal permeability. In the present narrative review, the crosstalk between gut microbiota products and intestinal homeostasis is discussed. Notably, gut-microbiota-related aspects have an impact on patients' clinical outcomes and overall survival. In accordance with the most recent published data, gut microbiota is crucial for the treatment effectiveness of many diseases, not only gastrointestinal cancers but also hematologic malignancies. Therefore, it is necessary to indicate a therapeutic method allowing to modulate gut microbiota in HSCT recipients. Currently, fecal microbiota transplantation (FMT) is the most innovative method used to alter/restore gut microbiota composition, as well as modulate its activity. Despite the fact that some previous data have shown promising results, the knowledge regarding FMT in HSCT is still strongly limited, except for the treatment of Clostridium difficile infection. Additionally, administration of prebiotics, probiotics, synbiotics, and postbiotics can also modify gut microbiota; however, this strategy should be considered carefully due to the high risk of fungemia/septicemia (especially in case of fungal probiotics).

Probiotics, Photobiomodulation, and Disease Management: Controversies and Challenges

In recent decades, researchers around the world have been studying intensively how micro-organisms that are present inside living organisms could affect the main processes of life, namely health and pathological conditions of mind or body. They discovered a relationship between the whole microbial colonization and the initiation and development of different medical disorders. Besides already known probiotics, novel products such as postbiotics and paraprobiotics have been developed in recent years to create new non-viable micro-organisms or bacterial-free extracts, which can provide benefits to the host with additional bioactivity to probiotics, but without the risk of side effects. The best alternatives in the use of probiotics and postbiotics to maintain the health of the intestinal microbiota and to prevent the attachment of pathogens to children and adults are highlighted and discussed as controversies and challenges. Updated knowledge of the molecular and cellular mechanisms involved in the balance between microbiota and immune system for the introspection on the gut-lung-brain axis could reveal the latest benefits and perspectives of applied photobiomics for health. Multiple interconditioning between photobiomodulation (PBM), probiotics, and the human microbiota, their effects on the human body, and their implications for the management of viral infectious diseases is essential. Coupled complex PBM and probiotic interventions can control the microbiome, improve the activity of the immune system, and save the lives of people with immune imbalances. There is an urgent need to seek and develop innovative treatments to successfully interact with the microbiota and the human immune system in the coronavirus crisis. In the near future, photobiomics and metabolomics should be applied innovatively in the SARS-CoV-2 crisis (to study and design new therapies for COVID-19 immediately), to discover how bacteria can help us through adequate energy biostimulation to combat this pandemic, so that we can find the key to the hidden code of communication between RNA viruses, bacteria, and our body.

Probiotics in Cancer

In recent years, the consumption of over-the-counter probiotics to promote health has grown rapidly worldwide and become an independent industry. In medicine, various studies have demonstrated that probiotics can help improve the immune system and intestinal health. They are usually safe, but in some rare cases, they may cause concerning adverse reactions. Although the use of probiotics has been widely popularized in the public, the results of many probiotic clinical trials are contradictory. Particularly in cancer patients, the feasibility of probiotic management providing benefits by targeting cancer and lessening anticancer side effects requires further investigation. This review summarizes the interactions between probiotics and the host as well as current knowledge on the pros and cons of utilizing probiotics in cancer patients.

Bi-Directional interactions between microbiota and ionizing radiation in head and neck and pelvic radiotherapy - clinical relevance

Purpose: Rapid developments in high throughput screening technology for the detection and identification of the human microbiota have helped in understanding its influence on human health and disease. In the recent past, several seminal studies have demonstrated the influence of microbiota on outcomes of therapy-associated radiation exposure. In this review, we highlight the concepts related to the mechanisms by which radiation alters the microbiota composition linked with radiation-associated toxicity in head and neck and pelvic regions. We further discuss specific microbial changes that can be employed as a biomarker for radiation and tumor response.Conclusion: Knowledge of the influence of microbiota in radiation response and advances in microbiota manipulation techniques would help to design personalized treatment augmenting the efficacy of radiotherapy.

Nutritional traditional and complementary medicine strategies in pediatric cancer: A narrative review

Traditional and complementary medicine (T&CM) strategies are commonly used by pediatric cancer patients. Nutritional approaches to T&CM include bioactive compounds, supplements, and herbs as well as dietary approaches. Pediatric cancer patients and their families commonly request and use nutritional T&CM strategies. We review the potential risks and benefits of nutritional T&CM use in pediatric cancer care and provide an overview of some commonly used and requested supplements, including probiotics, antioxidants, cannabinoids, vitamins, turmeric, mistletoe, Carica papaya, and others. We also discuss the role of specific diets such as the ketogenic diet, caloric restriction diets, whole-food diets, and immune modulating diets. There is a growing body of evidence to support the use of some T&CM agents for the supportive care of children with cancer. However, further study is needed into these agents and approaches. Open communication with families about T&CM use is critical.

Fungal Gut Microbiota Dysbiosis and Its Role in Colorectal, Oral, and Pancreatic Carcinogenesis

The association between bacterial as well as viral gut microbiota imbalance and carcinogenesis has been intensively analysed in many studies; nevertheless, the role of fungal gut microbiota (mycobiota) in colorectal, oral, and pancreatic cancer development is relatively new and undiscovered field due to low abundance of intestinal fungi as well as lack of well-characterized reference genomes. Several specific fungi amounts are increased in colorectal cancer patients; moreover, it was observed that the disease stage is strongly related to the fungal microbiota profile; thus, it may be used as a potential diagnostic biomarker for adenomas. Candida albicans, which is the major microbe contributing to oral cancer development, may promote carcinogenesis via several mechanisms, mainly triggering inflammation. Early detection of pancreatic cancer provides the opportunity to improve survival rate, therefore, there is a need to conduct further studies regarding the role of fungal microbiota as a potential prognostic tool to diagnose this cancer at early stage. Additionally, growing attention towards the characterization of mycobiota may contribute to improve the efficiency of therapeutic methods used to alter the composition and activity of gut microbiota. The administration of Saccharomyces boulardii in oncology, mainly in immunocompromised and/or critically ill patients, is still controversial.

An overview of yeast probiotics as cancer biotherapeutics: possible clinical application in colorectal cancer

The previous reports have established a strong link between diet, lifestyle, and gut microbiota population with the onset of the colorectal cancer (CRC). Administration of probiotics has become a particular interest in prevention and treatment of CRC. As potential dietary complements, probiotics might be able to lower the risk of CRC and manage the safety of traditional cancer therapies such as surgery, radiation therapy, and chemotherapy. This review investigates the promising effects of probiotics as biotherapeutics, with due attention to possible clinical application of yeast probiotics in prevention and treatment of CRC. In addition, various underlying anti-cancer mechanisms are covered here based on scientific evidence and findings from numerous experimental studies. Application of probiotics as biotherapeutics in CRC, however, needs to be approved by human clinical trials. It is of prime concern, to find potential probiotic strains, effective doses for administrations and regimes, and molecular mechanisms involved in prevention and treatment.

[Oral feeding of patient hospitalized for allogeneic stem cells transplantation: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Given the absence of consensus on oral feeding of patients undergoing allogeneic hematopoietic transplantation, the ninth workshops of practice harmonization of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) allocated one session to address this topic, especially during the hospitalization. A questionnaire was sent to all SFGM-TC pediatric and adult centers in order to investigate oral feeding practices. The results demonstrated a large disparity among centers regarding oral feeding. Here, we report our recommendations regarding the oral feeding after allogeneic hematopoietic cell transplantation in terms of quality, quantity and bacterial authorized load.

Complementary and alternative medicine use during chemotherapy for neuroendocrine tumours

Exploring the patient experience of complementary and alternative medicine (CAM) can provide insight into the needs, preferences and values of patients with an neuroendocrine tumour (NET). Use and interest in CAM after a NET diagnosis has not been investigated until now. The authors aimed to identify the types of CAM being used by patients undergoing chemotherapy and what types of CAM patients considered most beneficial. Patients were identified for clinical audit from one hospital's NET nurse chemotherapy database. A questionnaire was given to 79 patients who had completed intravenous chemotherapy during the previous 3 years. CAM use by NET patients was found to be popular and included practices to support both physical and emotional health. Massage and taking vitamin and mineral supplements were most widely used. The antioxidant effects of some high-dose supplements may impact on chemotherapy outcomes. Massage, despite its irregular use, was perceived by patients to be the most useful CAM.

The Role of the Microbiome in Cancer Initiation and Progression: How Microbes and Cancer Cells Utilize Excess Energy and Promote One Another's Growth

PURPOSE OF REVIEW

We use an ecological lens to understand how microbes and cancer cells coevolve inside the ecosystems of our bodies. We describe how microbe-cancer cell interactions contribute to cancer progression, including cooperation between microbes and cancer cells. We discuss the role of the immune system in preventing this apparent 'collusion' and describe how microbe-cancer cell interactions lead to opportunities and challenges in treating cancer.

RECENT FINDINGS

Microbiota influence many aspects of our health including our cancer risk. Since both microbes and cancer cells rely on incoming resources for their survival and replication, excess energy and nutrient input from the host can play a role in cancer initiation and progression. Certain microbes enhance cancer cell fitness by promoting proliferation and protecting cancer cells from the immune system. How diet influences these interactions remains largely unknown but recent evidence suggests a role for nutrients across the cancer continuum.

Experience with Saccharomyces boulardii Probiotic in Oncohaematological Patients

Very few reports have been published to date on the bloodstream infections caused by Saccharomyces spp. in oncohaematological patients, and there are no guidelines on the use of this probiotic microorganism in this population. We describe the use of probiotic preparation containing Saccharomyces boulardii in a large group of oncohaematological patients. We retrospectively analysed the data from 32,000 patient hospitalisations at the haematological centre during 2011–2013 (including 196 haematopoietic stem cell transplant recipients) in a tertiary care university-affiliated hospital. During the study period, 2270 doses of Saccharomyces boulardii probiotic were administered to the oncohaematological patients. In total, 2816 mycological cultures were performed, out of which 772 (27.4%) were positive, with 52 indicating digestive tract colonisation by Saccharomyces spp., mainly in patients with acute myeloid leukaemia (AML), myelodysplastic syndrome (MDS) or multiple myeloma (MM). While colonised, they were hospitalised for 1683 days and 416 microbiological cultures of their clinical samples were performed. In the studied group of patients, there were six blood cultures positive for fungi; however, they comprised Candida species: two C. glabrata, one C. albicans, one C. krusei, one C. tropicalis and one C. parapsilosis. There was no blood culture positive for Saccharomyces spp. Our study indicates that despite colonisation of many oncohaematological patients with Saccharomyces spp., there were no cases of fungal sepsis caused by this species.

Guideline for the Management of Clostridium Difficile Infection in Children and Adolescents With Cancer and Pediatric Hematopoietic Stem-Cell Transplantation Recipients

PURPOSE

The aim of this work was to develop a clinical practice guideline for the prevention and treatment of Clostridium difficile infection (CDI) in children and adolescents with cancer and pediatric hematopoietic stem-cell transplantation (HSCT) patients.

METHODS

An international multidisciplinary panel of experts in pediatric oncology and infectious diseases with patient advocate representation was convened. We performed systematic reviews of randomized controlled trials for the prevention or treatment of CDI in any population and considered the directness of the evidence to children with cancer and pediatric HSCT patients. We used the Grading of Recommendations Assessment, Development, and Evaluation approach to generate recommendations.

RESULTS

The panel made strong recommendations to administer either oral metronidazole or oral vancomycin for the initial treatment of nonsevere CDI and oral vancomycin for the initial treatment of severe CDI. Fidaxomicin may be considered in the setting of recurrent CDI. The panel suggested that probiotics not be routinely used for the prevention of CDI, and that monoclonal antibodies and probiotics not be routinely used for the treatment of CDI. A strong recommendation to not use fecal microbiota transplantation was made in this population. We identified key knowledge gaps and suggested directions for future research.

CONCLUSION

We present a guideline for the prevention and treatment of CDI in children and adolescents with cancer and pediatric HSCT patients. Future research should include randomized controlled trials that involve children with cancer and pediatric HSCT patients to improve the management of CDI in this population.

Pre-, pro- and synbiotics in cancer prevention and treatment-a review of basic and clinical research

There is a growing appreciation of the role of the human microbiota in the pathophysiology of cancer. Pre-, pro- and synbiotics are some of the best evidenced means of manipulating the microbiota for therapeutic benefit and their potential role in the prevention and treatment of cancer has garnered significant interest. In this review, we discuss how these agents may have oncosuppressive effects by maintaining intestinal barrier function, immunomodulation, metabolism and preventing host cell proliferation. We highlight the epidemiological and trials-based evidence supporting a role for pre-, pro- and synbiotics in the prevention of cancer. Ultimately, there is more evidence in support of these agents as adjuncts in the treatment of cancer. We discuss their roles in optimising the efficacy and/or minimising the adverse effects of chemotherapy and radiotherapy, antibiotics and surgery. Although we see significant promise in the application of pre-, pro- and synbiotics for clinical benefit in oncology patients, the field is very much in its infancy and oncologists face substantial challenges in advising their patients appropriately.

Saccharomyces cerevisiae Laryngitis and Oral Lesions in a Patient with Laryngeal Carcinoma

Saccharomyces cerevisiae is increasingly being promoted as a nutritional supplement by health food enthusiasts and is also recommended as prophylaxis against antibiotic-associated diarrhea. However, severe opportunistic infections due to S. cerevisiae have been reported in patients with chronic disease, cancer, and immunosuppression. Fungemia, endocarditis, pneumonia, peritonitis, urinary tract infections, skin infections, and esophagitis have been described. It is important to consider infections due to S. cerevisiae in appropriate clinical settings. Here, we describe the first case of S. cerevisiae laryngitis in a patient with a history of laryngeal carcinoma who also had oral lesions.

Saccharomyces cerevisiae fungemia after probiotic treatment in an intensive care unit patient

Saccharomyces cerevisiae is a common colonizer of the human gastrointestinal system as a benign organism. Enteral supplementation of this yeast as a probiotic product is effective in the treatment of antibiotic associated diarrhae. In rare occasions it can cause invasive infections. We present two fungemia cases in an intensive care unit following probiotic treatment containing S. boulardii. We are warning the safety of probiotic treatment in critically ill patients.

Can Consideration of the Microbiome Improve Antimicrobial Utilization and Treatment Outcomes in the Oncology Patient?

The need to provide effective and timely antimicrobial treatment to cancer patients with infections is well recognized but tempered by preliminary, but accumulating, evidence that antibiotic-induced microbiome dysbiosis affects cancer therapy response, noninfectious toxicities, and infectious complications. Given only a minority of empirically treated cancer patients are proven to have a true bacterial infection, it is important to consider the potential negative consequences of extensive broad-spectrum antimicrobial use on the commensal microbiota. Herein, we review the literature substantiating the dilemma oncologists face when treating suspected or documented infections with respect to the interaction between the host microbiome, antibiotics, and cancer-related clinical outcomes. We propose microbiome-based explorations that could assist oncologists in optimizing treatment strategies for cancer-related infections as well as the cancer itself. In addition, we discuss knowledge gaps and challenges in this nascent field that must be addressed to deliver medically relevant, translational applications. We anticipate that the emerging knowledge regarding the role of the microbiota in the health of cancer patients may cause a reappraisal of the manner in which antibiotics are used in the oncologic setting and how microorganisms are viewed by oncologists. Clin Cancer Res; 23(13); 3263-8. ©2017 AACRSee related commentary by Fessler and Gajewski, p. 3229.

Catheter-related Saccharomyces cerevisiae Fungemia Following Saccharomyces boulardii Probiotic Treatment: In a child in intensive care unit and review of the literature

Although Saccharomyces boulardii is usually a non-pathogenic fungus, in rare occasions it can cause invasive infection in children. We present the case of an 8-year-old patient in pediatric surgical intensive care unit who developed S. cerevisiae fungemia following probiotic treatment containing S. boulardii. Caspofungin was not effective in this case and he was treated with amphotericin B. We want to emphasize that physicians should be careful about probiotic usage in critically ill patients.

Seven cases of Saccharomyces fungaemia related to use of probiotics

Probiotics are increasingly used in critically ill patients without enough safety data. The aim of the present study was to determine the association of probiotics with Saccharomyces cerevisiae fungaemia. Seven patients with S. cerevisiae fungaemia were reported at two hospitals in India between July 2014 and September 2015. Detailed clinical history of patients was recorded. Besides the seven patient isolates, three probiotics sachets used in those patients and five unrelated clinical isolates were used for association study by Fluorescent amplified fragment length polymorphism (FAFLP). Antifungal susceptibility testing was performed by broth microdilution technique of CLSI (M27-A3) and interpreted according to CLSI (M27S4). Two patients were premature neonates and five were adults. They were admitted in intensive care unit and were on probiotics containing S. boulardii (except one adult patient). FAFLP analysis showed 96.4-99.7% similarity between blood and corresponding probiotic isolates. Of the three AFLP types (group I, II, II) identified, all the probiotic isolates clustered in group I (major cluster) including majority of the blood isolates. The isolates were susceptible to all antifungal agents tested. Five patients, who could be evaluated, responded promptly to echinocandins or voriconazole. As the prescription of probiotic containing S. boulardii in critically ill patient's leads to the fungaemia, we recommend avoiding this probiotic in those patients.

Nutrition Issues in Hematopoietic Stem Cell Transplantation: State of the Art

There have been many changes in hematopoietic stem cell transplantation (HSCT) that affect the patient's nutrition support. In the early 1970s, allogeneic transplants were the most common types of HSCTs; today, autologous transplants are the most common. Bone marrow, peripheral blood, and umbilical cord blood all now serve as sources of stem cells. Conditioning therapies include myeloablative, reduced-intensity myeloablative, and nonmyeloablative regimens. New medications are being developed and used to minimize the toxicities of the conditioning therapy and to minimize infectious complications. Supportive therapies for renal and liver complications have changed. In the past, HSCT patients received parenteral nutrition (PN) throughout their hospitalization and sometimes as home therapy. Because of medical complications and cost issues associated with PN, many centers are now working to use less PN and increase use of enteral nutrition. The immunosuppressed diet has changed from a sterile diet prepared under laminar-flow hoods to a more liberal diet that avoids high-risk foods and emphasizes safety in food handling practices. This article will review these changes in HSCT and the impact of these changes on the nutrition support of the patient.

Probiotic Survey in Cancer Patients Treated in the Outpatient Department in a Comprehensive Cancer Center

Purpose. Availability without prescription restriction, low cost, and simple oral administration allow cancer patients to use probiotics without knowledge of potential risks. We present a survey of probiotic use and the association with patient tumor characteristics in cancer patients treated at the outpatient department of the National Cancer Institute in Slovakia. Patients and Methods. Between March and December 2014, 499 patients were asked to evaluate their overall experience with probiotics by questionnaire form, including the length and method of use relative to anticancer therapy, expectations, side-effect experiences, understanding of the possible risks, dietary supplement use, and others. The relevant data were statistically evaluated. Results. The cohort consisted of 323 women (64.7%) and 176 men (35.3%); 91.6% were undergoing chemotherapy (2.6% together with radiotherapy) and 8.4% had no anticancer therapy. The prevalence of probiotic use was 28.5% and only 12 patients using probiotics (8.5%) described negative side effects. Most patients declared consideration of probiotic use based on recommendation from a physician (37.3%) or a pharmacist (14.8%). Nevertheless, up to 86.6% of patients declared no knowledge of possible risks. Statistically significant correlation was found between probiotic use and age of patients (P < .008), gender (P < .023), and taking other dietary supplements (P < .000002). Conclusions. In this prospective study, we present for the first time the prevalence, side-effect experience, and aspects that most likely influence probiotic use in cancer patients. Minimal knowledge of risks underlines the importance of an active approach by oncologists to inform patients about probiotic safety.

Saccharomyces cerevisiae UFMG A-905 treatment reduces intestinal damage in a murine model of irinotecan-induced mucositis

Indigenous microbiota plays a crucial role in the development of several intestinal diseases, including mucositis. Gastrointestinal mucositis is a major and serious side effect of cancer therapy, and there is no effective therapy for this clinical condition. However, some probiotics have been shown to attenuate such conditions. To evaluate the effects of Saccharomyces cerevisiae UFMG A-905 (Sc-905), a potential probiotic yeast, we investigated whether pre- or post-treatment with viable or inactivated Sc-905 could prevent weight loss and intestinal lesions, and maintain integrity of the mucosal barrier in a mucositis model induced by irinotecan in mice. Only post-treatment with viable Sc-905 was able to protect mice against the damage caused by chemotherapy, reducing the weight loss, increase of intestinal permeability and jejunal lesions (villous shortening). Besides, this treatment reduced oxidative stress, prevented the decrease of goblet cells and stimulated the replication of cells in the intestinal crypts of mice with experimental mucositis. In conclusion, Sc-905 protects animals against irinotecan-induced mucositis when administered as a post-treatment with viable cells, and this effect seems to be related with the reduction of oxidative stress and preservation of intestinal mucosa.

Risk and safety of probiotics

Probiotics have been used safely for years. Safety outcomes are inconsistently reported in published clinical trials. In 2011, a report released by the Agency for Healthcare Research and Quality concluded that, although the existing probiotic clinical trials reveal no evidence of increased risk, "the current literature is not well equipped to answer questions on the safety of probiotics in intervention studies with confidence." Critics point out that the preponderance of evidence, including the long history of safe probiotic use as well as data from clinical trials, and animal and in vitro studies all support the assumption that probiotics are generally safe for most populations. Theoretical risks have been described in case reports, clinical trial results and experimental models, include systemic infections, deleterious metabolic activities, excessive immune stimulation in susceptible individuals, gene transfer and gastrointestinal side effects. More research is needed to properly describe the incidence and severity of adverse events related to probiotics.

The multifaceted role of commensal microbiota in homeostasis and gastrointestinal diseases

The gastrointestinal tract houses a complex and diverse community of microbes. In recent years, an increased understanding of the importance of intestinal microbiota for human physiology has been gained. In the steady state, commensal microorganisms have a symbiotic relationship with the host and possess critical and distinct functions, including directly influencing immunity. This means that recognition of commensal antigens is necessary for the development of complete immune responses. Therefore, the immune system must face the challenge of maintaining mucosal homeostasis while dealing with undue passage of commensal or pathogenic microbes, as well as the host nutritional status or drug use. Disruption of this fine balance has been associated with the development of several intestinal inflammatory diseases. In this review, we discuss the mechanisms involved in the modulation of host-microbe interactions and how the breakdown of this homeostatic association can lead to intestinal inflammation and pathology.

Efficacy and safety of Saccharomyces boulardii for acute diarrhea

BACKGROUND AND OBJECTIVE

The efficacy of Saccharomyces boulardii for treatment of childhood diarrhea remains unclear. Our objective was to systematically review data on the effect of S. boulardii on acute childhood diarrhea.

METHODS

Our data sources included Medline, Embase, CINAHL, Scopus, and The Cochrane Library up to September 2013 without language restrictions. Randomized controlled trials and non-randomized trials that evaluated effectiveness of S. boulardii for treatment of acute diarrhea in children were included. Two reviewers independently evaluated studies for eligibility and quality and extracted the data.

RESULTS

In total, 1248 articles were identified, of which 22 met the inclusion criteria. Pooling data from trials showed that S. boulardii significantly reduced the duration of diarrhea (mean difference [MD], -19.7 hours; 95% confidence interval [CI], -26.05 to -13.34), stool frequency on day 2 (MD, -0.74; 95% CI, -1.38 to -0.10) and day 3 (MD, -1.24; 95% CI, -2.13 to -0.35), the risk for diarrhea on day 3 (risk ratio [RR], 0.41; 95% CI, 0.27 to 0.60) and day 4 (RR, 0.38; 95% CI, 0.24 to 0.59) after intervention compared with control. The studies included in this review were varied in the definition of diarrhea, the termination of diarrhea, inclusion and exclusion criteria, and their methodological quality.

CONCLUSIONS

This review and meta-analysis show that S. boulardii is safe and has clear beneficial effects in children who have acute diarrhea. However, additional studies using head-to-head comparisons are needed to define the best dosage of S. boulardii for diarrhea with different causes.

Pathogenic potential of Saccharomyces strains isolated from dietary supplements

Saccharomyces cerevisiae plays a beneficial role in health because of its intrinsic nutritional value and bio-functional properties, which is why it is also used as a dietary supplement. However, the perception that S. cerevisiae is harmless has changed due to an increasing number of infections caused by this yeast. Given this scenario, we have tested whether viable strains contained in dietary supplements displayed virulence-associated phenotypic traits that could contribute to virulence in humans. We have also performed an in vivo study of the pathogenic potential of these strains using a murine model of systemic infection by intravenous inoculation. A total of 5 strains were isolated from 22 commercial products and tested. Results highlight one strain (D14) in terms of burden levels in brains and kidneys and ability to cause death, whereas the other two strains (D2 and D4) were considered of low virulence. Our results suggest a strong relationship between some of the virulence-associated phenotypic traits (ability to grow at 39°C and pseudohyphal growth) and the in vivo virulence in a mouse model of intravenous inoculation for isolates under study. The isolate displaying greatest virulence (D14) was evaluated in an experimental murine model of gastrointestinal infection with immunosuppression and disruption of mucosal integrity, which are common risk factors for developing infection in humans, and results were compared with an avirulent strain (D23). We showed that D14 was able to spread to mesenteric nodes and distant organs under these conditions. Given the widespread consumption of dietary supplements, we recommend only safe strains be used.

The efficacy and safety of probiotics in people with cancer: a systematic review

BACKGROUND

Probiotics are living microorganisms that are generally thought of as being beneficial to the recipient. They have been shown to be effective in people with acute infectious diarrhoea, and cost-effective in antibiotic-associated diarrhoea. Probiotics may have a role in people with cancer, as various cancer treatments often lead to diarrhoea. However, as people with cancer are often immunocompromised, it is important to assess for adverse events (AEs) such as infection, which could potentially be a consequence of deliberate ingestion of living microorganisms.

DESIGN

A systematic review was carried out to collect, analyse and synthesise all available data on the efficacy and safety of probiotics in people with cancer (PROSPERO registration: CRD42012003454). Randomised, controlled trials, identified through screening multiple databases and grey literature, were included for analysing efficacy, while all studies were included for the analysis of safety of probiotics. Primary outcomes were the reduction in duration, severity and incidence of antibiotic-associated diarrhoea and chemotherapy-associated diarrhoea, and AEs, especially probiotic-associated infection. Where possible, data were combined for meta-analysis by a random-effects model, assessing causes of heterogeneity, including differences in strains, dosage and patient characteristics.

RESULTS

Eleven studies (N = 1557 participants) were included for assessing efficacy. Results show that probiotics may reduce the severity and frequency of diarrhoea in patients with cancer and may reduce the requirement for anti-diarrhoeal medication, but more studies are needed to assess the true effect. For example comparing probiotic use to control 25 groups on effect on Common Toxicity Criteria ≥2 grade diarrhoea, odds ratio (OR) = 0.32 [95% confidence interval (CI) of 0.13-0.79; P = 0.01]. Seventeen studies (N = 1530) were included in the safety analysis. Five case reports showed probiotic-related bacteraemia/fungaemia/positive blood cultures.

CONCLUSIONS

Probiotics may be a rare cause of sepsis. Further evidence needs to be collated to determine whether probiotics provide a significant overall benefit for people with cancer.

Probiotic bacteria in cancer patients undergoing chemotherapy and radiation therapy

BACKGROUND

Probiotics are live microorganisms, which as drugs or food supplements help to maintain health beneficial microbial balance in the digestive tract of a human or other host. Probiotics by their properties may help strengthen homeostasis and thus reduce side effects associated with cancer treatment. Experimental evidence suggests that probiotics might have beneficial effect on the toxicity of anticancer therapy.

METHODS

A computer-based literature search was carried out using PubMed (keywords: "probiotic" and "lactic acid bacteria" in association with the search terms "cancer" or "oncology" or "chemotherapy" or "radiation"); data reported at international meetings were included.

RESULTS

Probiotics might have beneficial effects on some aspects of toxicity related to anticancer treatment especially radiation therapy. However, reported trials vary in utilized probiotic strains, dose of probiotics and vast majority of them are small trials with substantial risk of bias. Despite limited data, it seems that probiotic bacteria as live microorganisms could be safely administered even in the setting of neutropenia.

CONCLUSIONS

Current evidence supporting probiotic use as adjunctive therapy to anticancer treatment is limited, especially in cancer patients treated with chemotherapy. Well designed clinical trials are needed to find true role of probiotics in oncology.

Probiotics for prevention of nosocomial infections: efficacy and adverse effects

PURPOSE OF REVIEW

In this era of increasing antimicrobial resistance, use of probiotics in infection prevention has brought new perspective. However, in 2008 the, until then considered, safe use of probiotics became an important topic after publication of a trial showing excess mortality in patients on probiotic prophylaxis. In this article, we review the concept of infection prevention by probiotics and the present knowledge of the efficacy of probiotics in prevention of infections among patients with abdominal diseases and in intensive care. Safety issues of probiotics will be discussed extensively.

RECENT FINDINGS

Over 30 clinical trials with probiotics to prevent infections have been published, some of which were prematurely stopped recently. Studies with critically ill patients and patients with abdominal diseases showed conflicting results regarding the effects of probiotics on infection rates, as did meta-analyses. These studies are difficult to compare because different probiotics were used which all have different efficacy and safety profiles.

SUMMARY

The efficacy of probiotics in infection prevention among critically ill patients is still not unequivocally determined. The safety profile differs per probiotic strain and should not be generalized towards other strains and patient populations. A well designed and well powered clinical trial with clear endpoints to demonstrate efficacy is warranted.

Use of probiotics in gastrointestinal disorders: what to recommend?

Perturbation of bacterial microflora of the gastrointestinal (GI) tract may play an important role in the pathophysiology of some GI disorders. Probiotics have been used as a treatment modality for over a century. They may restore normal bacterial microflora and effect the functioning of the GI tract by a variety of mechanisms. Probiotics are not currently regulated and only few randomized controlled trials exist investigating their efficacy in different GI disorders. They are available in a variety of formulations and delivery systems making interpretation and comparison of studies even more difficult. The efficacy of probiotics, either as a single strain or a combination of probiotics, has been tested in antibiotic-associated diarrhea, Clostridium difficile colitis, infectious diarrhea, ulcerative colitis, Crohn's disease, pouchitis, and irritable bowel syndrome, among other disorders. Results of the studies are reviewed in this article and recommendations for probiotic use in these disorders are made. Although probiotics appear to be generally safe in an outpatient setting, the situation may be different in immunocompromised, hospitalized patients who may be at a greater risk of developing probiotic sepsis. No studies exist addressing the issue of safety specifically. Many questions regarding use of probiotics in GI disorders remain to be answered in future studies, such as most optimal doses, duration of treatment, physiological and immunological effects, efficacy of specific probiotics in specific disease states, and safety in debilitated patients.

Safety of probiotics in patients receiving nutritional support: a systematic review of case reports, randomized controlled trials, and nonrandomized trials

BACKGROUND

Probiotics are increasingly used in patients receiving nutritional support; however, some case reports and trials have questioned their safety in such patients.

OBJECTIVE

The objective was to investigate the safety of probiotics in patients receiving nutritional support through a systematic review of case reports, randomized controlled trials (RCTs), and nonrandomized trials.

DESIGN

The systematic review followed Cochrane and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) recommendations. Six electronic databases were searched, a hand search of conference proceedings and reference lists was performed, and experts were contacted. Case reports, RCTs, and nonrandomized trials of probiotic use in patients also receiving enteral or parenteral nutrition were included in the review. Two reviewers independently screened the relevant articles and extracted the data.

RESULTS

In total, 1966 articles were identified, of which 72 fulfilled the inclusion criteria. There were 20 case reports of adverse events in 32 patients, all of which were infections due to Lactobacillus rhamnosus GG or Saccharomyces boulardii; the risk factors included central venous catheters and disorders associated with increased bacterial translocation. There were 52 articles reporting 53 trials in which 4131 patients received probiotics. Most trials showed either no effect or a positive effect on outcomes related to safety (eg, mortality and infections). Only 3 trials showed increased complications, which were largely noninfectious in nature and in specific patient groups (eg, transplant and pancreatitis). In 2 of these trials, the probiotic was administered through a postpyloric tube.

CONCLUSION

Many probiotics have been used safely in patients receiving nutritional support, although some probiotic products (strains or combinations) have been shown to increase the risk of complications in specific patient groups.

Saccharomyces cerevisiae: population divergence and resistance to oxidative stress in clinical, domesticated and wild isolates

BACKGROUND

Saccharomyces cerevisiae has been associated with human life for millennia in the brewery and bakery. Recently it has been recognized as an emerging opportunistic pathogen. To study the evolutionary history of S. cerevisiae, the origin of clinical isolates and the importance of a virulence-associated trait, population genetics and phenotypic assays have been applied to an ecologically diverse set of 103 strains isolated from clinics, breweries, vineyards, fruits, soil, commercial supplements and insect guts.

METHODOLOGY/PRINCIPAL FINDINGS

DNA sequence data from five nuclear DNA loci were analyzed for population structure and haplotype distribution. Additionally, all strains were tested for survival of oxidative stress, a trait associated with microbial pathogenicity. DNA sequence analyses identified three genetic subgroups within the recombining S. cerevisiae strains that are associated with ecology, geography and virulence. Shared alleles suggest that the clinical isolates contain genetic contribution from the fruit isolates. Clinical and fruit isolates exhibit high levels of recombination, unlike the genetically homogenous soil isolates in which no recombination was detected. However, clinical and soil isolates were more resistant to oxidative stress than any other population, suggesting a correlation between survival in oxidative stress and yeast pathogenicity.

CONCLUSIONS/SIGNIFICANCE

Population genetic analyses of S. cerevisiae delineated three distinct groups, comprising primarily the (i) human-associated brewery and vineyard strains, (ii) clinical and fruit isolates (iii) and wild soil isolates from eastern U.S. The interactions between S. cerevisiae and humans potentiate yeast evolution and the development of genetically, ecologically and geographically divergent groups.