What Do We Know about the Microbiome in Cystic Fibrosis? Is There a Role for Probiotics and Prebiotics?

The gastrointestinal microbiome, small bowel bacterial overgrowth, and microbiome modulators in cystic fibrosis

People with cystic fibrosis (pwCF) have an altered gastrointestinal microbiome. These individuals also demonstrate propensity toward developing small intestinal bacterial overgrowth (SIBO). The dysbiosis present has intestinal and extraintestinal implications, including potential links with the higher rates of gastrointestinal malignancies described in CF. Given these implications, there is growing interest in therapeutic options for microbiome modulation. Alternative therapies, including probiotics and prebiotics, and current CF transmembrane conductance regulator gene modulators are promising interventions for ameliorating gut microbiome dysfunction in pwCF. This article will characterize and discuss the current state of knowledge and expert opinions on gut dysbiosis and SIBO in the context of CF, before reviewing the current evidence supporting gut microbial modulating therapies in CF.

Impact of high-dose cholecalciferol (vitamin D3) and inulin prebiotic on intestinal and airway microbiota in adults with cystic fibrosis: A 2 × 2 randomized, placebo-controlled, double-blind pilot study

Background

Cystic fibrosis (CF) is a multi-organ disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR). Individuals with CF often have gastrointestinal (GI) dysbiosis due to chronic inflammation and antibiotic use. Previous studies suggested a role for vitamin D in reversing the GI dysbiosis found in CF.

Objective

To explore the potential role of a combination of high-dose oral cholecalciferol (vitamin D3) and fermentable dietary fiber, inulin, to impact bacterial composition, richness, and diversity of intestinal and airway microbiota in adults with CF.

Methods

This was a 2 × 2 factorial, double-blinded, placebo-controlled, randomized, pilot clinical trial in which adults with CF received oral cholecalciferol (vitamin D3) (50,000 IU/week) and/or inulin (12 g/day) for 12 weeks. Thus, there were 4 study groups (n = 10 subjects per group); 1) placebo 2) vitamin D3 3) inulin 4) vitamin D3 plus inulin. Stool and sputum samples were collected at baseline (just before) and after the intervention and were analysed using 16S ribosomal RNA gene sequencing for gut and airway microbiota composition. Statistical analyses assessed alpha and beta diversity to evaluate microbial community changes.

Results

Of a total of 254 screened participants, 40 eligible participants were randomized to one of the 4 treatment arms. Participants receiving vitamin D3 plus inulin exhibited greater changes in microbiome indexes in both intestinal and airway relative to those in the other study groups. Specific taxonomic changes supported the potential beneficial influence of this combination to mitigate both intestinal and airway dysbiosis in adults with CF.

Conclusion

This pilot study established that the combination of oral vitamin D3 and the prebiotic inulin was well tolerated over 12 weeks in adults with CF and altered gut and airway bacterial communities. Future research appear warranted to define clinical outcomes and the role of microbiota changes therein with this approach.

Clinical outcomes of potential coeliac disease: a systematic review and meta-analysis

OBJECTIVE

Potential coeliac disease (PCD) is characterised by positive serological and genetic markers of coeliac disease with architecturally preserved duodenal mucosa. The clinical outcomes and rates of progression to overt coeliac disease in patients with PCD remain uncertain. In this systematic review and meta-analysis, we aimed to evaluate the clinical outcomes of patients with PCD.

DESIGN

We searched Medline, Embase, Scopus and Cochrane Library from 1991 through May 2024 to identify studies evaluating the clinical outcomes of patients with PCD. The progression rates to villous atrophy, seroconversion and response to a gluten-free diet (GFD) were analysed. A random-effect meta-analysis was performed, and the results were reported as pooled proportions with 95% CIs.

RESULTS

Seventeen studies comprising 1010 patients with PCD were included in the final analyses. The pooled prevalence of PCD among patients with suspected coeliac disease was 16% (95% CI 10% to 22%). The duration of follow-up in most of the studies was at least 1 year, with follow-up periods within individual studies ranging from 5 months to 13 years. During follow-up, 33% (95% CI 18% to 48%; I2=96.4%) of patients with PCD on a gluten-containing diet developed villous atrophy, and 33% (95% CI 17% to 48%; I2=93.0%) had normalisation of serology. Among those who adhered to a GFD, 88% (95% CI 79% to 97%; I2=93.2%) reported symptomatic improvement.

CONCLUSION

Almost a third of patients with PCD develop villous atrophy over time, whereas a similar proportion experience normalisation of serology despite a gluten-containing diet. Most symptomatic patients benefit from a GFD. These findings highlight the importance of structured follow-up and individualised management for patients with PCD.

The effect of Lactobacillus reuteri on pulmonary function test and growth of cystic fibrosis patients

INTRODUCTION

Cystic fibrosis (CF) patients frequently experience gut microbiota dysbiosis. Probiotic supplementation is a potential therapeutic approach to modify gut microbiota and improve CF management through the gut-lung axis. The aim of this study was to investigate the effect of Lactobacillus reuteri supplementation on pulmonary function test, respiratory symptoms and growth in CF patients.

METHODS

A randomized, placebo-controlled clinical trial was carried out on 40 children with CF aged from 6 to 20 years. Participants were designated to receive either L. reuteri or placebo daily for 4 months. Pulmonary function tests, weight, height and body mass index (BMI) z-scores were measured pre and post treatment.

RESULTS

The median baseline BMI of the patients was 16.28 kg m-2. A significant change in the probiotic group's BMI z-score after the study period was observed (P = 0.034) but not for weight and height z-scores (P > 0.05). After treatment, Pseudomonas aeruginosa grew in sputum cultures of seven in the placebo and one patient in the intervention group (P = 0.03) while at baseline it grew in the sputum of four patients in each group. There was no significant difference in forced expiratory volume in the first second, forced expiratory flow at 25-75% or forced vital capacity change between the two groups after the treatment period (P > 0.05). Additionally, no significant differences were found in pulmonary exacerbations, hospitalization frequencies or COVID-19 infection between the two groups during the study (P > 0.05).

CONCLUSION

The results suggest that L. reuteri supplementation may impact the growth of severely malnourished CF patients. Furthermore, it may be concluded that this strain might reduce P. aeruginosa in the sputum culture of CF patients. © 2024 Society of Chemical Industry.

In vitro screening of the impact of dietary prebiotic components, probiotic strains, and their symbiotic combinations on colonic microbiota in children with cystic fibrosis

Children with Cystic Fibrosis (CF) are more likely to have intestinal dysbiosis due to recurrent antibiotic therapy and the conventional hypercaloric diet administered to them. This study aimed at evaluating the effect of isolated prebiotic components and probiotic strains, and their combinations as potential synbiotics, on the intestinal microbiota of CF children. A static in vitro colonic fermentation model was used by colonizing vials with faecal inoculum, a culture medium, and the substrates to be tested. Post treatment, aliquots were taken to determine ammonium, lactate, and short-chain fatty acids production and to profile the microbiota composition by 16s rRNA sequencing. At genus level, Escherichia-Shigella decreased (15.8%) with the treatment pectin + L. rhamnosus, followed by the beta-glucan + L. salivarius (15.5%). Inversely, the most increase in Bacteroides (44%) was obtained by the treatment with Pectin + L. reuteri. Lactate and acetic acid production was significantly increased with prebiotics and their combinations with L. rhamnosus and L. salivarius. In conclusion, the use of beta-glucan and pectin in combination with probiotic strains from the Lactobacillaceae family suggest potential to modulate dysbiosis and metabolic activity on CF colonic microbiota, encouraging further studies in animal studies or clinical settings to confirm the findings in vivo.

Exhaled breath analysis in adult patients with cystic fibrosis by real-time proton mass spectrometry

BACKGROUND

Proton-transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS) is a promising tool for a rapid online determination of exhaled volatile organic compounds (eVOCs) profiles in patients with cystic fibrosis (CF).

OBJECTIVE

To detect VOC breath signatures specific to adult patients with CF compared with controls using PTR-TOF-MS.

METHODS

102 CF patients (54 M/48, mean age 25.6 ± 7.8 yrs) and 97 healthy controls (56 M/41F, mean age 25.8 ± 6.0 yrs) were examined. Samples from normal quiet breathing and forced expiratory maneuvers were analyzed with PTR-TOF-MS (Ionicon, Austria) to obtain VOC profiles listed as ions at various mass-to-charge ratios (m/z).

RESULTS

PTR-TOF-MS analysis was able to detect 167 features in exhaled breath from CF patients and healthy controls. According to cluster analysis and LASSO regression, patients with CF and controls were separated. The most significant VOCs for CF were indole, phenol, dimethyl sulfide, and not indicated: m/z = 297.0720 ([C12H13N2O7 and C17H13O5]H + ), m/z = 281.0534 ([C19H7NO2, C12H11NO7 and C16H9O5]H + ) during five-fold cross-validation both in forced expiratory maneuver and in normal quiet breathing.

CONCLUSION

PTR-TOF-MS is a promising method for determining the molecular composition of exhaled air specific to CF.

Evolution of nutritional management in children with cystic fibrosis - a narrative review

Nutrition has played a central role in the management and outcomes of people with cystic fibrosis (pwCF) since the 1970s. Advances in therapies and practices in recent decades have led to a significant change in the patient landscape with dramatic improvements in life expectancy, as well as quality of life, bringing with it new issues. Historically, cystic fibrosis was a condition associated with childhood and malnutrition; however, changes in patient demographics, nutritional assessment and fundamental nutritional management have evolved, and it has become an increasingly prevalent adult disease with new nutritional challenges, including obesity. This paper aims to describe these changes and the impact and challenges they bring for those working in this field. Nutritional professionals will need to evolve, adapt and remain agile to the wider range of situations and support required for a new generation of pwCF. Specialised nutrition support will continue to be required, and it will be additionally important to improve and optimise quality of life and long-term health.

Faecal lipid profile as a new marker of fat maldigestion, malabsorption and microbiota

BACKGROUND

Fat malabsorption in children with cystic fibrosis (CF) leads to poor nutritional status and altered colonic microbiota. This study aimed at establishing the faecal lipid profile in children with CF, and exploring associations between the faecal lipidome and microbiota.

METHODS

Cross-sectional observational study with children with CF and an age-matched control group. Faecal lipidome was analysed by UHLC-HRMS and microbiota profiling by 16S rRNA amplicon sequencing.

RESULTS

Among 234 identified lipid species, five lipidome clusters (LC) were obtained with significant differences in triacylglycerols (TG), diacylglycerols (DG), monoacylglycerols (MG) and fatty-acids (FA): LC1 subjects with good digestion and absorption: low TG and low MG and FA; LC2 good digestion and poor absorption: low TG and high MG and FA; LC3 Mild digestion and poor absorption: intermediate TG and high MG and FA; LC4 poor digestion and absorption: high TG and high MG and FA; LC5 outliers. Bacteroidota and Verrucomicrobiota decreased over LC1-LC4, while Proteobacteria increased. Nutritional status indicators were significantly higher in LC1 and decreased over LC2-LC4.

CONCLUSION

Assessing faecal lipidome may be relevant to determine how dietary lipids are digested and absorbed. This new evidence might be a method to support targeted nutritional interventions towards reverting fat maldigestion or malabsorption.

IMPACT

Lipidomic analysis enabled the identification of the lipid species related to maldigestion (triglycerides) or malabsorption (monoglycerides and fatty acids). Children with cystic fibrosis can be grouped depending on the faecal lipidome profile related to dietary fat maldigestion or malabsorption. The lipidome profile in faeces is related to the composition of microbiota and nutritional status indicators.

Effect of beta-glucan supplementation on cystic fibrosis colonic microbiota: an in vitro study

BACKGROUND

Children with cystic fibrosis (CF) present with gut dysbiosis, and current evidence impedes robust recommendations on the use of prebiotics. This study aimed at establishing the prebiotic potential of a commercial beta-glucan on the in vitro colonic microbiota of a child with CF compared to a healthy counterpart (H).

METHODS

A dynamic simulator of colonic fermentation (twin-SHIME® model) was set up including the simulation of the proximal (PC) and distal colon (DC) of the CF and the H subjects by colonizing the bioreactors with faecal microbiota. During two weeks the system was supplied with the beta-glucan. At baseline, during treatment and post-treatment, microbiota composition was profiled by 16 S rRNA and short-chain fatty acids (SCFA) production was determined by GS-MS.

RESULTS

At baseline, Faecalibacterium, was higher in CF' DC than in the H, along higher Acidaminococcus and less Megasphaera and Sutterella. Beta-glucan supplementation induced increased microbiota richness and diversity in both subjects during the treatment. At genus level, Pseudomonas and Veillonella decreased, while Akkermansia and Faecalibacterium increased significantly in CF.

CONCLUSION

The supplementation with beta-glucan suggests positive results on CF colonic microbiota in the in vitro context, encouraging further research in the in vivo setting.

IMPACT

Current evidence supports assessing the effect of prebiotics on modifying cystic fibrosis microbiota. The effect of beta-glucan supplementation was evaluated in a controlled dynamic in vitro colonic ecosystem. Beta-glucan supplement improved diversity in cystic fibrosis colonic microbiota. The treatment showed increased abundance of Faecalibacterium and Akkermansia in cystic fibrosis. New evidence supports the use of prebiotics in future clinical studies.

Cystic fibrosis and fat malabsorption: Pathophysiology of the cystic fibrosis gastrointestinal tract and the impact of highly effective CFTR modulator therapy

Cystic fibrosis (CF) is a progressive, genetic, multi-organ disease affecting the respiratory, digestive, endocrine, and reproductive systems. CF can affect any aspect of the gastrointestinal (GI) tract, including the esophagus, stomach, small intestine, colon, pancreas, liver, and gall bladder. GI pathophysiology associated with CF results from CF membrane conductance regulator (CFTR) dysfunction. The majority of people with CF (pwCF) experience exocrine pancreatic insufficiency resulting in malabsorption of nutrients and malnutrition. Additionally, other factors can cause or worsen fat malabsorption, including the potential for short gut syndrome with a history of meconium ileus, hepatobiliary diseases, and disrupted intraluminal factors, such as inadequate bile salts, abnormal pH, intestinal microbiome changes, and small intestinal bacterial overgrowth. Signs and symptoms associated with fat malabsorption, such as abdominal pain, bloating, malodorous flatus, gastroesophageal reflux, nausea, anorexia, steatorrhea, constipation, and distal intestinal obstruction syndrome, are seen in pwCF despite the use of pancreatic enzyme replacement therapy. Given the association of poor nutrition status with lung function decline and increased mortality, aggressive nutrition support is essential in CF care to optimize growth in children and to achieve and maintain a healthy body mass index in adults. The introduction of highly effective CFTR modulator therapy and other advances in CF care have profoundly changed the course of CF management. However, GI symptoms in some pwCF may persist. The use of current knowledge of the pathophysiology of the CF GI tract as well as appropriate, individualized management of GI symptoms continue to be integral components of care for pwCF.

Nutritional considerations for people living with a Fontan circulation: a narrative review

The population of people living with a Fontan circulation are highly heterogenous, including both children and adults, who have complex health issues and comorbidities associated with their unique physiology throughout life. Research focused on nutritional considerations and interventions in the Fontan population is extremely limited beyond childhood. This review article discusses the current literature examining nutritional considerations in the setting of Fontan physiology and provides an overview of the available evidence to support nutritional management strategies and future research directions. Protein-losing enteropathy, growth deficits, bone mineral loss, and malabsorption are well-recognised nutritional concerns within this population, but increased adiposity, altered glucose metabolism, and skeletal muscle deficiency are also more recently identified issues. Emergencing evidence suggets that abnormal body composition is associated with poor circulatory function and health outcomes. Many nutrition-related issues, including the impact of congenital heart disease on nutritional status, factors contributing to altered body composition and comorbidities, as well as the role of the microbiome and metabolomics, remain poodly understood.

Diagnosis and Management of Gastrointestinal Manifestations in Children with Cystic Fibrosis

Cystic fibrosis (CF) is primarily known for its pulmonary consequences, which are extensively explored in the existing literature. However, it is noteworthy that individuals with CF commonly display gastrointestinal (G-I) manifestations due to the substantial presence of the cystic fibrosis transmembrane conductance regulator (CFTR) protein in the intestinal tract. Recognized as pivotal nonpulmonary aspects of CF, G-I manifestations exhibit a diverse spectrum. Identifying and effectively managing these manifestations are crucial for sustaining health and influencing the overall quality of life for CF patients. This review aims to synthesize existing knowledge, providing a comprehensive overview of the G-I manifestations associated with CF. Each specific G-I manifestation, along with the diagnostic methodologies and therapeutic approaches, is delineated, encompassing the impact of innovative treatments targeting the fundamental effects of CF on the G-I tract. The findings underscore the imperative for prompt diagnosis and meticulous management of G-I manifestations, necessitating a multidisciplinary team approach for optimal care and enhancement of the quality of life for affected individuals. In conclusion, the authors emphasize the urgency for further clinical studies to establish a more robust evidence base for managing G-I symptoms within the context of this chronic disease. Such endeavors are deemed essential for advancing understanding and refining the clinical care of CF patients with G-I manifestations.

Effect of Lactobacillaceae Probiotics on Colonic Microbiota and Metabolite Production in Cystic Fibrosis: A Comparative In Vitro Study

Cystic Fibrosis-related gut dysbiosis (CFRGD) has become a recognised complication in children with this condition, and current evidence remains insufficient to guide the selection of probiotic strains for supplementation treatments. The aim of this study was to characterise the effect of three probiotic strains on CFRGD by means of a dynamic in vitro simulation of the colonic fermentation (SHIME®). The configuration of the system included three bioreactors colonised with the faecal inoculum of a child with cystic fibrosis. For 20 days, each bioreactor was supplied daily with either Lacticaseibacillus rhamnosus GG (ATCC 53103 TM), Limosilactobacillus reuteri (DSM 17938) or Lactiplantibacillus plantarum (DSM 22266). The baseline microbiota was characterised by a high abundance of Prevotella, Faecalibacterium and Acidaminococcus genera. After 20 days of supplementation, L. rhamnosus and L. plantarum reduced Prevotella significantly, and the three strains led to increased Faecalibacterium and Bifidobacterium and decreased Acidaminococcus, with some of these changes being maintained 10 days after ceasing supplementation. The metabolic activity remained unaltered in terms of short-chain fatty acids, but branched-chain fatty acids showed a significant decrease, especially with L. plantarum. Additionally, ammonia decreased at 20 days of supplementation, and lactate continuously increased with the three strains. The effects on colonic microbiota of L. rhamnosus, L. reuteri or L. plantarum were established, including increased beneficial bacteria, such as Faecalibacterium, and beneficial metabolites such as lactate; and on the other hand, a reduction in pathogenic genera, including Prevotella or Acidaminococcus and branched-chain fatty acids, overall supported their use as probiotics in the context of CFRGD.

Early life high fructose exposure disrupts microglia function and impedes neurodevelopment

Despite the success of fructose as a low-cost food additive, recent epidemiological evidence suggests that high fructose consumption by pregnant mothers or during adolescence is associated with disrupted neurodevelopment 1-7 . An essential step in appropriate mammalian neurodevelopment is the synaptic pruning and elimination of newly-formed neurons by microglia, the central nervous system's (CNS) resident professional phagocyte 8-10 . Whether early life high fructose consumption affects microglia function and if this directly impacts neurodevelopment remains unknown. Here, we show that both offspring born to dams fed a high fructose diet and neonates exposed to high fructose exhibit decreased microglial density, increased uncleared apoptotic cells, and decreased synaptic pruning in vivo . Importantly, deletion of the high affinity fructose transporter SLC2A5 (GLUT5) in neonates completely reversed microglia dysfunction, suggesting that high fructose directly affects neonatal development. Mechanistically, we found that high fructose treatment of both mouse and human microglia suppresses synaptic pruning and phagocytosis capacity which is fully reversed in GLUT5-deficient microglia. Using a combination of in vivo and in vitro nuclear magnetic resonance- and mass spectrometry-based fructose tracing, we found that high fructose drives significant GLUT5-dependent fructose uptake and catabolism, rewiring microglia metabolism towards a hypo-phagocytic state. Importantly, mice exposed to high fructose as neonates exhibited cognitive defects and developed anxiety-like behavior which were rescued in GLUT5-deficient animals. Our findings provide a mechanistic explanation for the epidemiological observation that early life high fructose exposure is associated with increased prevalence of adolescent anxiety disorders.

Can Bioactive Food Substances Contribute to Cystic Fibrosis-Related Cardiovascular Disease Prevention?

Advances in cystic fibrosis (CF) care have significantly improved the quality of life and life expectancy of patients. Nutritional therapy based on a high-calorie, high-fat diet, antibiotics, as well as new therapies focused on CFTR modulators change the natural course of the disease. They do so by improving pulmonary function and growing BMI. However, the increased weight of such patients can lead to unwanted long-term cardiovascular effects. People with CF (pwCF) experience several cardiovascular risk factors. Such factors include a high-fat diet and increased dietary intake, altered lipid metabolism, a decrease in the level of fat-soluble antioxidants, heightened systemic inflammation, therapeutic interventions, and diabetes mellitus. PwCF must pay special attention to food and eating habits in order to maintain a nutritional status that is as close as possible to the proper physiological one. They also have to benefit from appropriate nutritional counseling, which is essential in the evolution and prognosis of the disease. Growing evidence collected in the last years shows that many bioactive food components, such as phytochemicals, polyunsaturated fatty acids, and antioxidants have favorable effects in the management of CF. An important positive effect is cardiovascular prevention. The possibility of preventing/reducing cardiovascular risk in CF patients enhances both quality of life and life expectancy in the long run.

A systematic review of the colorectal microbiome in adult cystic fibrosis patients

AIM

Cystic fibrosis (CF) is a hereditary, life-limiting, multi-system condition that results in chronic respiratory infections, pancreatic insufficiency and intestinal inflammation. Evidence indicates that CF patients develop colorectal cancer (CRC) earlier and more often than the general population. Intestinal dysbiosis resulting from genetics and CF treatment is a contributing factor. This systematic review aims to evaluate the literature to compare the microbiome of adult CF patients to non-CF patients and to assess if these changes correspond with known CRC microbiome alterations.

METHODS

A systematic review across five databases was performed according to PRISMA guidelines. Studies focusing on adult CF patients using next generation sequencing and with appropriate non-CF controls were included. Two reviewers independently screened results and assessed study quality using the Newcastle-Ottawa scale.

RESULTS

The search generated 2757 results. 118 studies were retained after reviewing the title/abstract and full article review found five studies met the inclusion criteria. All studies consistently showed reduced microbial diversity in CF patients and unique clustering between CF and control cohorts. Thirty-four genera and 27 species were differently expressed between CF and controls. The CF cohort had a reduced number of short-chain fatty acid (SCFA) producing bacteria and a higher abundance of bacteria associated with CRC compared to controls.

CONCLUSION

There was substantial heterogeneity across all the studies with regard to methodologies and reporting. However, all studies consistently found CF patients had reduced microbial diversity, fewer SCFA producing bacteria and increased CRC-associated bacteria. Further prospective studies employing consistent multi-omics approaches are needed to improve our understanding of the CF gut microbiome and its involvement in early onset CRC.

SIGNIFICANCE STATEMENT

This is the first systematic review to assess adult CF colorectal microbiome changes. This study shows CF patients have reduced SCFA producing bacteria and increased CRC-associated bacteria compared to non-CF patients and may help to explain the increased risk of CRC in the CF cohort.

Probiotic knowledge of adults with cystic fibrosis is limited but is associated with probiotic use: A cross-sectional survey study

Background: Probiotics are used by people with cystic fibrosis (CF) and other chronic diseases to manage gastrointestinal symptoms. Aim: To describe probiotic knowledge; its relationship with probiotic use, probiotic information sources and factors influencing choice in adults with CF and a general population control group. Methods: A cross-sectional questionnaire study was conducted in adults with CF (n = 205) and Controls (n = 158). Probiotic knowledge was compared between CF and Controls using a knowledge score (maximum 5) based on predefined criteria: (1a) bacteria/microorganism; (1b) live; (2a) administered; (2b) adequate dose and (3) health benefit, using independent samples t-test. Two-way analysis of variance explored knowledge scores between CF and Control and between Ever User and Never User groups. Chi-square and Fisher's exact tests compared knowledge criterion, probiotic sources and influences on probiotic choice between groups. Thematic analysis of open-text responses explored probiotic-related knowledge and influences on probiotic decision making. Results: Knowledge scores (mean ± SD) did not differ between CF (1.70 ± 1.12) and Controls (1.89 ± 0.99), p = 0.13. Probiotic use was associated with knowledge score (p < 0.001). More CF Ever Users than Never Users correctly identified criteria 1a (65% vs. 38%), 1b (16% vs. 0%), 2a (45% vs. 22%) and 3 (73% vs. 42%) (all p < 0.005). CF participants considered 'dairy yoghurt' (69%), 'live cultures' (64%) and 'fermented foods' (37%) as 'all/mostly' probiotic sources. The internet was the commonest source of probiotic-related information. Conclusion: Probiotic knowledge and use were associated in adults with CF. Understanding of probiotic characteristics and sources were limited. Education is needed to help guide patient probiotic decision making.

Probiotics Administration in Cystic Fibrosis: What Is the Evidence?

In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.

CFTR and Gastrointestinal Cancers: An Update

Cystic Fibrosis (CF) is a disease caused by mutations in the CFTR gene that severely affects the lungs as well as extra-pulmonary tissues, including the gastrointestinal (GI) tract. CFTR dysfunction resulting from either mutations or the downregulation of its expression has been shown to promote carcinogenesis. An example is the enhanced risk for several types of cancer in patients with CF, especially cancers of the GI tract. CFTR also acts as a tumor suppressor in diverse sporadic epithelial cancers in many tissues, primarily due to the silencing of CFTR expression via multiple mechanisms, but especially due to epigenetic regulation. This review provides an update on the latest research linking CFTR-deficiency to GI cancers, in both CF patients and in sporadic GI cancers, with a particular focus on cancer of the intestinal tract. It will discuss changes in the tissue landscape linked to CFTR-deficiency that may promote cancer development such as breakdowns in physical barriers, microbial dysbiosis and inflammation. It will also discuss molecular pathways and mechanisms that act upstream to modulate CFTR expression, such as by epigenetic silencing, as well as molecular pathways that act downstream of CFTR-deficiency, such as the dysregulation of the Wnt/β-catenin and NF-κB signaling pathways. Finally, it will discuss the emerging CFTR modulator drugs that have shown promising results in improving CFTR function in CF patients. The potential impact of these modulator drugs on the treatment and prevention of GI cancers can provide a new example of personalized cancer medicine.