Probiotics, fibre and herbal medicinal products for functional and inflammatory bowel disorders

Functional bowel disorders (FBD), mainly irritable bowel syndrome (IBS) and functional constipation (FC, also called chronic idiopathic constipation), are very common worldwide. Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, although less common, has a strong impact on patients' quality of life, as well as being highly expensive for our healthcare. A definite cure for those disorders is still yet to come. Over the years, several therapeutic approaches complementary or alternative to traditional pharmacological treatments, including probiotics, prebiotics, synbiotics, fibre and herbal medicinal products, have been investigated for the management of both groups of diseases. However, most available studies are biased by several drawbacks, including small samples and poor methodological quality. Probiotics, in particular Saccharomyces boulardii and Lactobacilli (among which Lactobacillus rhamnosus), synbiotics, psyllium, and some herbal medicinal products, primarily peppermint oil, seem to be effective in ameliorating IBS symptoms. Synbiotics and fibre seem to be beneficial in FC patients. The probiotic combination VSL#3 may be effective in inducing remission in patients with mild-to-moderate ulcerative colitis, in whom Escherichia coli Nissle 1917 seems to be as effective as mesalamine in maintaining remission. No definite conclusions can be drawn as to the efficacy of fibre and herbal medicinal products in IBD patients due to the low number of studies and the lack of randomized controlled trials that replicate the results obtained in the individual studies conducted so far. Thus, further, well-designed studies are needed to address the real role of these therapeutic options in the management of both FBD and IBD.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

The Role of Antibiotics in Gut Microbiota Modulation: The Eubiotic Effects of Rifaximin

Antibiotics are mainly used in clinical practice for their activity against pathogens, but they also alter the composition of commensal gut microbial community. Rifaximin is a non-absorbable antibiotic with additional effects on the gut microbiota about which very little is known. It is still not clear to what extent rifaximin can be able to modulate gut microbiota composition and diversity in different clinical settings. Studies based on culture-dependent techniques revealed that rifaximin treatment promotes the growth of beneficial bacteria, such as Bifidobacteria and Lactobacilli. Accordingly, our metagenomic analysis carried out on patients with different gastrointestinal and liver diseases highlighted a significant increase in Lactobacilli after rifaximin treatment, persisting in the short time period. This result was independent of the disease background and was not accompanied by a significant alteration of the overall gut microbial ecology. This suggests that rifaximin can exert important eubiotic effects independently of the original disease, producing a favorable gut microbiota perturbation without changing its overall composition and diversity.

Physiology and pathophysiology of liver lipid metabolism

Liver lipid metabolism and its modulation are involved in many pathologic conditions, such as obesity, non-alcoholic fatty liver disease, diabetes mellitus, atherosclerosis and cardiovascular disease. Metabolic disorders seem to share a similar background of low-grade chronic inflammation, even if the pathophysiological mechanisms leading to tissue and organ damage have not been completely clarified yet. The accumulation of neutral lipids in the liver is now recognized as a beneficial and protective mechanism; on the other hand, lipoperoxidation is involved in the development and progression of non-alcoholic steatohepatitis. The role of the gut microbiota in liver lipid metabolism has been the object of recent scientific investigations. It is likely that the gut microbiota is involved in a complex metabolic modulation and the translocation of gut microflora may also contribute to maintaining the low-grade inflammatory status of metabolic syndrome. Therefore, lipid metabolism pathology has vague limits and complex mechanisms, and the knowledge of these is essential to guide diagnostic and therapeutic decisions.

Esophageal microbiome signature in patients with Barrett's esophagus and esophageal adenocarcinoma

Preliminary studies suggested a possible correlation of microbiota with Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC), where the need for tools to ameliorate its poor prognosis is mandatory. We explored the potential signature of esophageal microbiota and its predicted functional profile along the continuous spectrum from BE to EAC. We analyzed through 16S-based amplicon sequencing the mucosal microbiota and the microbiota-related functional predictions in 10 BE and 6 EAC patients compared with 10 controls, exploring also potential differences between the metaplastic mucosa (BEM) and the adjacent normal areas of BE patients (BEU). BEM and EAC showed a higher level of α and β-diversity. BEM evidenced a decrease of Streptococcus and an increase of Prevotella, Actinobacillus, Veillonella, and Leptotrichia. EAC displayed a striking reduction of Streptococcus, with an increase of Prevotella, Veillonella and Leptotrichia. LefSe analysis identified Leptotrichia as the main taxa distinguishing EAC. BEM showed a decreased α-diversity compared with BEU and a reduction of Bacteroidetes, Prevotella and Fusobacterium. Functional predictions identified peculiar profiles for each group with a high potential for replication and repair in BEM; an upregulated energy, replication and signaling metabolisms, with the fatty-acids biosynthesis and nitrogen and D-alanine pathways down-regulated in EAC. Our pilot study identifies a unique microbial structure and function profile for BE and EAC, as well as for metaplastic and near-normal areas. It proposes a new concept for BE, which could be intended not only as the histological, but, also, as the microbial closest precursor of EAC. This requires further larger follow-up studies, but opens intriguing horizons towards innovative diagnostic and therapeutic options for EAC.

Digestive Enzyme Supplementation in Gastrointestinal Diseases

BACKGROUND

Digestive enzymes are able to break down proteins and carbohydrates and lipids, and their supplementation may play a role in the management of digestive disorders, from lactose intolerance to cystic fibrosis. To date, several formulations of digestive enzymes are available on the market, being different each other in terms of enzyme type, source and origin, and dosage.

METHODS

This review, performed through a non-systematic search of the available literature, will provide an overview of the current knowledge of digestive enzyme supplementation in gastrointestinal disorders, discussion of the use of pancreatic enzymes, lactase (β-galactosidase) and conjugated bile acids, and also exploring the future perspective of digestive enzyme supplementation.

RESULTS

Currently, the animal-derived enzymes represent an established standard of care, however the growing study of plant-based and microbe-derived enzymes offers great promise in the advancement of digestive enzyme therapy.

CONCLUSION

New frontiers of enzyme replacement are being evaluated also in the treatment of diseases not specifically related to enzyme deficiency, whereas the combination of different enzymes might constitute an intriguing therapeutic option in the future.

Effect of rifaximin on gut microbiota composition in advanced liver disease and its complications

Liver cirrhosis is a paradigm of intestinal dysbiosis. The qualitative and quantitative derangement of intestinal microbial community reported in cirrhotic patients seems to be strictly related with the impairment of liver function. A kind of gut microbial “fingerprint”, characterized by the reduced ratio of “good” to “potentially pathogenic” bacteria has recently been outlined, and is associated with the increase in Model for End-Stage Liver Disease and Child Pugh scores. Moreover, in patients presenting with cirrhosis complications such as spontaneous bacterial peritonitis (SBP), hepatic encephalopathy (HE), and, portal hypertension intestinal microbiota modifications or the isolation of bacteria deriving from the gut are commonly reported. Rifaximin is a non-absorbable antibiotic used in the management of several gastrointestinal diseases. Beyond bactericidal/bacteriostatic, immune-modulating and anti-inflammatory activity, a little is known about its interaction with gut microbial environment. Rifaximin has been demonstrated to exert beneficial effects on cognitive function in patients with HE, and also to prevent the development of SBP, to reduce endotoxemia and to improve hemodynamics in cirrhotics. These results are linked to a shift in gut microbes functionality, triggering the production of favorable metabolites. The low incidence of drug-related adverse events due to the small amount of circulating drug makes rifaximin a relatively safe antibiotic for the modulation of gut microbiota in advanced liver disease.

Predictors of failure after single faecal microbiota transplantation in patients with recurrent Clostridium difficile infection: results from a 3-year, single-centre cohort study

OBJECTIVES

Faecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection (CDI). Although a single faecal infusion is usually sufficient to eradicate CDI, a considerable number of patients need multiple infusions to be cured. The aim of this study was to identify predictors of failure after single faecal infusion in patients with recurrent CDI.

METHODS

We included patients with recurrent CDI prospectively treated with FMT by colonoscopy. By means of univariate and multivariate analysis, variables including female gender, age, number of CDI recurrences, severity of CDI, hospitalization, inadequate bowel preparation, unrelated donor, and use of frozen faeces, were assessed to predict failure after single faecal infusion.

RESULTS

Sixty-four patients (39 women; mean age 74 years) were included. Of them, 44 (69%) were cured by a single faecal infusion, whereas 20 (31%) needed repeat infusions. Overall, FMT cured 62 of 64 (97%) patients. In the subgroup of patients with severe CDI, only eight of 26 (30%) were cured with a single infusion. At multivariate analysis, severe CDI (OR 24.66; 95% CI 4.44-242.08; p 0.001) and inadequate bowel preparation (OR 11.53; 95% CI 1.71-115.51; p 0.019) were found to be independent predictors of failure after single faecal infusion.

CONCLUSIONS

Severe CDI and inadequate bowel preparation appear to be independent predictors of failure after single faecal infusion in patients treated with FMT by colonoscopy for recurrent CDI. Our results may help to optimize protocols and outcomes of FMT in patients with recurrent CDI.

Colon capsule endoscopy in colorectal cancer screening: a systematic review

INTRODUCTION

Primary colonoscopy and fecal immunochemical test (FIT) are the most commonly used colorectal cancer (CRC) screening modalities. Colon capsule endoscopy (CCE) might be an alternative. Data on the performance of CCE as a CRC screening tool in a screening population remain scarce. This is the first systematic review to provide an overview of the applicability of CCE as a CRC screening tool.

METHODS

A systematic search was conducted of literature published up to September 2020. Studies reporting on CRC screening by second-generation CCE in an average-risk screening population were included.

RESULTS

582 studies were identified and 13 were included, comprising 2485 patients. Eight studies used CCE as a filter test after a positive FIT result and five studies used CCE for primary screening. The polyp detection rate of CCE was 24 % - 74 %. For polyps > 6 mm, sensitivity of CCE was 79 % - 96 % and specificity was 66 % - 97 %. For polyps ≥ 10 mm, sensitivity of CCE was 84 % - 97 %, which was superior to computed tomographic colonography (CTC). The CRC detection rate for completed CCEs was 93 % (25/27). Bowel preparation was adequate in 70 % - 92 % of examinations, and completion rates varied from 57 % to 92 %, depending on the booster used. No CCE-related complications were described.

CONCLUSION

CCE appeared to be a safe and effective tool for the detection of CRC and polyps in a screening setting. Accuracy was comparable to colonoscopy and superior to CTC, making CCE a good alternative to colonoscopy in CRC screening programs, although completion rates require improvement.

Evaluation of a new pan-enteric video capsule endoscopy system in patients with suspected or established inflammatory bowel disease - feasibility study

Background and study aims  Inflammatory bowel disease (IBD) affects the small bowel and colon. Endoscopic evaluation of these organs is essential. The new pan-enteric Crohn's capsule (PCC) system is customized for complete coverage of IBD lesions in the entire bowel, allowing assessment and follow-up of disease severity and extent. The aim of this study was to evaluate the functionality of the PCC system in patients with suspected or established IBD. Patients and methods  This was a prospective five-center feasibility study assessing the performance of PCC. Subjects ingested PCC after patency assurance with standard bowel preparation plus boosts. The primary endpoint was successful procedure, that is, video creation and report generation in accordance with methodology. Secondary endpoints were subjective coverage of the entire bowel, duration of reading time, video quality and occurrence of adverse events. Results  Forty-one patients were included in the study with a mean age of 40.8 years ± 15.5, 46 % of whom were males. Seventy-one percent of patients had established Crohn's disease (CD) and 53 % had active disease. Cleansing was graded good/excellent in 95 %. All 41 videos met the primary endpoint. There was no retention, 83 % reached the toilet while still recording. Thirty-one percent of patients with CD had proximal disease. Bowel coverage was graded 6.7 ± 0.6 and 6.1 ± 1.3 (1 - 7, unconfident - confident), image quality 6.1 ± 0.8 (1 - 7, poor - excellent), and reading time 3.7 ± 1.4 (1 - 7, very short to very long). Conclusions  The PCC system is a minimally invasive system allowing extensive evaluation of the entire bowel in patients with IBD.

Imaging alternatives to colonoscopy: CT colonography and colon capsule. European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastrointestinal and Abdominal Radiology (ESGAR) Guideline - Update 2020

1: ESGE/ESGAR recommend computed tomographic colonography (CTC) as the radiological examination of choice for the diagnosis of colorectal neoplasia.Strong recommendation, high quality evidence.ESGE/ESGAR do not recommend barium enema in this setting.Strong recommendation, high quality evidence. 2: ESGE/ESGAR recommend CTC, preferably the same or next day, if colonoscopy is incomplete. The timing depends on an interdisciplinary decision including endoscopic and radiological factors.Strong recommendation, low quality evidence.ESGE/ESGAR suggests that, in centers with expertise in and availability of colon capsule endoscopy (CCE), CCE preferably the same or the next day may be considered if colonoscopy is incomplete.Weak recommendation, low quality evidence. 3: When colonoscopy is contraindicated or not possible, ESGE/ESGAR recommend CTC as an acceptable and equally sensitive alternative for patients with alarm symptoms.Strong recommendation, high quality evidence.Because of lack of direct evidence, ESGE/ESGAR do not recommend CCE in this situation.Very low quality evidence.ESGE/ESGAR recommend CTC as an acceptable alternative to colonoscopy for patients with non-alarm symptoms.Strong recommendation, high quality evidence.In centers with availability, ESGE/ESGAR suggests that CCE may be considered in patients with non-alarm symptoms.Weak recommendation, low quality evidence. 4: Where there is no organized fecal immunochemical test (FIT)-based population colorectal screening program, ESGE/ESGAR recommend CTC as an option for colorectal cancer screening, providing the screenee is adequately informed about test characteristics, benefits, and risks, and depending on local service- and patient-related factors.Strong recommendation, high quality evidence.ESGE/ESGAR do not suggest CCE as a first-line screening test for colorectal cancer.Weak recommendation, low quality evidence. 5: ESGE/ESGAR recommend CTC in the case of a positive fecal occult blood test (FOBT) or FIT with incomplete or unfeasible colonoscopy, within organized population screening programs.Strong recommendation, moderate quality evidence.ESGE/ESGAR also suggest the use of CCE in this setting based on availability.Weak recommendation, moderate quality evidence. 6: ESGE/ESGAR suggest CTC with intravenous contrast medium injection for surveillance after curative-intent resection of colorectal cancer only in patients in whom colonoscopy is contraindicated or unfeasibleWeak recommendation, low quality evidence.There is insufficient evidence to recommend CCE in this setting.Very low quality evidence. 7: ESGE/ESGAR suggest CTC in patients with high risk polyps undergoing surveillance after polypectomy only when colonoscopy is unfeasible.Weak recommendation, low quality evidence.There is insufficient evidence to recommend CCE in post-polypectomy surveillance.Very low quality evidence. 8: ESGE/ESGAR recommend against CTC in patients with acute colonic inflammation and in those who have recently undergone colorectal surgery, pending a multidisciplinary evaluation.Strong recommendation, low quality evidence. 9: ESGE/ESGAR recommend referral for endoscopic polypectomy in patients with at least one polyp ≥ 6 mm detected at CTC or CCE.Follow-up CTC may be clinically considered for 6 - 9-mm CTC-detected lesions if patients do not undergo polypectomy because of patient choice, comorbidity, and/or low risk profile for advanced neoplasia.Strong recommendation, moderate quality evidence.

Accuracy of colon capsule endoscopy for advanced neoplasia

BACKGROUND AND AIMS

Second-generation colon capsule endoscopy (CCE-2) has shown promising accuracy for the diagnosis of overall neoplasia. Advanced neoplasia (AN) represents the main target of colorectal cancer screening programs. Our aim was to assess the diagnostic accuracy of CCE-2 for the detection of AN in patients with a positive result for the fecal immunochemical test (FIT) who are undergoing screening.

METHODS

Patients aged 50 to 69 years with a positive result for the FIT in 4 population screening programs in Italy and Spain were enrolled. Screenees were asked to undergo CCE-2, followed by traditional colonoscopy (TC). TC was performed the same day or the following morning. Bowel preparation included a split-dose polyethylene glycol-based regimen, with sodium phosphate (NaP) with gastrografin as boosters. The CCE-2 video was read by an endoscopist blinded to the results of TC. The main outcomes were CCE-2 accuracy in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for AN when using 2 different size thresholds for TC referral (ie, polyps ≥6 mm and ≥10 mm).

RESULTS

Two hundred twenty-two patients were enrolled, and 178 patients completed both CCE-2 and TC (87.7%). Overall, 59 cases of AN were detected at TC. CCE-2 sensitivity was 90%, specificity was 66.1%, PPV was 57.4%, and NPV was 92.9% for AN when using a 6-mm cut-off (TC referral rate, 52.8%) and 76.7%, 90.7%, 80.7%, and 88.4% when using a 10-mm cut-off (TC referral rate, 32%), respectively. CCE-2 detected that 8 of 9 already developed colorectal cancers. Among the 41 false positives at the 6-mm cut-off, 34 (82.9%) presented with a nonadvanced adenoma at TC. Mean transit time was 4 hours and 4 minutes, and ≥70% of patients excreted the capsule within 5 hours.

CONCLUSIONS

In an enriched disease setting, we showed the high sensitivity of CCE-2 for the diagnosis of AN at a 6-mm cut-off. The apparently low CCE-2 specificity is related to the choice of AN as the main outcome. (Clinical trial registration number: ISRCTN 62158762.).

Nickel free-diet enhances the Helicobacter pylori eradication rate: a pilot study

BACKGROUND

The Helicobacter pylori eradication rate with standard triple therapy is very low. H. pylori is known to require the nickel-containing metalloenzymes urease and NiFe-hydrogenase to survive at the low pH environment in the stomach.

AIM

To compare the H. pylori eradication rate of a nickel free-diet associated with standard triple therapy and standard triple therapy alone as the first-line regimen.

METHODS

Fifty-two sex- and age-matched patients at the first diagnosis of H. pylori infection were randomized 1:1 into two different therapeutic schemes: (1) standard LCA (26 patients): lansoprazole 15 mg bid, clarithromycin 500 mg bid and amoxicillin 1,000 mg bid for 7 days with a common diet; (2) standard LCA plus a nickel free-diet (NFD-LCA) (26 patients). Patients followed 30 days of a nickel-free diet plus a week of lansoprazole 15 mg bid, clarithromycin 500 mg bid and amoxicillin 1,000 mg bid starting from day 15 of the diet.

RESULTS

All patients completed the study. A significantly higher eradication rate was observed in the NFD-LCA group (22/26) versus LCA group (12/26) (p < 0.01). Only a few patients (9 of 52) reported the occurrence of mild therapy-related side effects, without any significant differences between the two groups.

CONCLUSIONS

The addition of a nickel-free diet to standard triple therapy significantly increases the H. pylori eradication rate. The reduction of H. pylori urease activity due to the nickel-free diet could expose the bacterium to gastric acid and increase H. pylori's susceptibility to amoxicillin. Further studies are necessary to confirm this preliminary result.

Efficacy and Mechanisms of Action of Fecal Microbiota Transplantation in Ulcerative Colitis: Pitfalls and Promises From a First Meta-Analysis

BACKGROUND

Inflammatory bowel disease (IBD) is the results of a chronic inflammatory process deriving from disequilibrium between self-microbiota composition and immune response.

METHODS

New evidence, coming from Clostridium difficile infection, clearly showed that active and powerful modulation of microbiota composition by fecal microbiota composition (FMT) is safe, easy to perform, and efficacious, opening new frontiers in gastrointestinal and extra-intestinal diseases. FMT has been proposed also for IBD as well as other non-gastrointestinal conditions related to intestinal microbiota dysfunctions, with good preliminary data.

RESULTS

In this setting, ulcerative colitis (UC) represents one of the most robust potential indications for FMT after C difficile colitis.

CONCLUSIONS

In the present review, we focus on FMT and its application on ulcerative colitis, clarifying mechanisms of actions and efficacy data, trough completion of a meta-analysis on available randomized, controlled trial data in UC. Because microbiota is so crucially involved in this topic, a short review of microbial alterations in UC will also be performed.

Principles of DNA-Based Gut Microbiota Assessment and Therapeutic Efficacy of Fecal Microbiota Transplantation in Gastrointestinal Diseases

Fecal microbiota transplantation (FMT), a process by which the normal gastrointestinal microbiota is restored, has demonstrated extraordinary cure rates for Clostridium difficile infection and low recurrence. The community of microorganisms within the human gut (or microbiota) is critical to health status and functions; therefore, together with the rise of FMT, the gastrointestinal microbiota has emerged as a 'virtual' organ with a level of complexity comparable to that of any other organ system and capable to compete with powerful known antibiotics for the treatment of several disorders. Although treatment protocols, donor selection, stool preparation and delivery methods varied widely, with a few reports following an identical protocol, FMT has diffused to other areas where the alterations of the gut microbiota ecology (or dysbiosis) have been theorized to play a causative role, including inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), among several other extra-intestinal disorders (i.e. metabolic syndrome and obesity, multiple sclerosis, cardiovascular diseases). FMT can be relatively simple to perform, but a number of challenges need to be overcome before this procedure is widely accepted in clinical practice, and currently, there is no consensus between the various gastrointestinal organizations and societies regarding the FMT procedure. In this article, we describe the modern high-throughput sequencing techniques to characterize the composition of gut microbiota and the potential for therapeutics by manipulating microbiota with FMT in several gastrointestinal disorders (C. difficile-associated diarrhea, IBD and IBS), with a look on the potential future directions of FMT.

Gut microbiota and inflammatory bowel disease: so far so gut!

Major advances have occurred in the knowledge of the pathogenesis of inflammatory bowel disease (IBD) over the last decade, and perhaps the most major, and clinically advantageous of these advances has been the discovery of the microbiome as a key multifaceted component of inflammation. The gut microbiome is the largest known group of cells in the body, and is now recognized as an organ in its own right. Initial studies looking at a possible role of bacterial manipulation of the immune system in IBD, looked at identifying a specific bacterial species, and were not representative of a feasible model of inflammation in IBD overall. More recently there has been a shift towards the concept of dysbiosis, and the acceptance that a number of bacterial factors interact with the immune system in order for inflammation to occur. In the present review we will focus on past perspective of the role of microbiota in IBD, current evidences about dysbiosis in IBD and also the main therapeutic modalities to affect IBD by affecting gut microbiota: probiotics, prebiotics, fecal microbiota transplantation and emerging dietary intervention.

Rifaximin for the treatment of irritable bowel syndrome - a drug safety evaluation

INTRODUCTION

Irritable bowel syndrome is a functional gastrointestinal disorder with a multifactorial etiology. Alterations of intestinal motility and immunity, gut-brain interactions, as well as gut microbiota dysbiosis contribute to the development of irritable bowel syndrome. Therefore, gut microbiota modulation by non-absorbable antibiotics is a therapeutic option in patients with IBS.

AREAS COVERED

Published articles including patients with irritable bowel syndrome reporting data about rifaximin activity and safety have been searched throughout the literature and selected.

EXPERT OPINION

The optimal antibiotic molecule should be local-acting, long-acting and safe-acting. Rifaximin is a non-absorbable antibiotic with additional anti-inflammatory and gut microbiota-modulating activity. It is effective in inducing symptoms relief in patients with IBS, even after repeated treatment courses. Rifaximin-related side effects in patients with IBS are reported to be mild and infrequent; microbial resistance is rare and transient, due to the high local concentration of the drug and to the absence of horizontal transmission. Clostridium difficile infection is not usual in patients receiving rifaximin in absence of predisposing conditions such as hospitalization and immunosuppression, which are uncommon in patients affected by irritable bowel syndrome. Nevertheless rifaximin is an antibiotic active against Clostridium difficile infection. Rifaximin has limited metabolic interactions and is not expected to interfere with drug metabolism in patients with normal hepatic function. These properties make rifaximin a safe antibiotic for gut microbiota modulation in patients with IBS.

Bacterial flora as a cause or treatment of chronic diarrhea

Intestinal microflora can be considered an organ of the body. It has several functions in the human gut, mostly metabolic and immunologic, and constantly interacts with the intestinal mucosa in a delicate equilibrium. Chronic diarrhea is associated with an alteration of gut microbiota when a pathogen invades the gut and also in several conditions associated with intestinal mucosal damage or bowel dysfunction, as in inflammatory bowel disease, irritable bowel syndrome, or small bowel bacterial overgrowth. This article discusses the basis of gut microbiota modulation. Evidence for the efficacy of gut microbiota modulation in chronic conditions is also discussed.

Colonoscopy quality across Europe: a report of the European Colonoscopy Quality Investigation (ECQI) Group

Background and study aims  The European Colonoscopy Quality Investigation (ECQI) Group comprises expert colonoscopists and investigators with the aim of raising colonoscopy standards. We assessed the levels of monitoring and achievement of European Society of Gastrointestinal Endoscopy (ESGE) performance measures (PMs) across Europe using responses to the ECQI questionnaires. Methods  The questionnaire comprises three forms: institution and practitioner questionnaires are completed once; a procedure questionnaire is completed on multiple occasions for individual total colonoscopies. ESGE PMs were approximated as closely as possible from the data collected via the procedure questionnaire. Procedure data could provide rate of adequate bowel preparation, cecal intubation rate (CIR), withdrawal time, polyp detection rate (PDR), and tattooing resection sites. Results  We evaluated ECQI questionnaire data collected between June 2016 and April 2018, comprising 91 practitioner and 52 institution questionnaires. A total of 6445 completed procedure forms were received. Institution and practitioner responses indicate that routine recording of PMs is not widespread: adenoma detection rate (ADR) is routinely recorded in 29 % of institutions and by 34 % of practitioners; PDR by 42 % and 47 %, CIR by 62 % and 64 %, bowel preparation quality by 56 % and 76 %, respectively. Procedure data showed a rate of adequate bowel preparation of 84.2 %, CIR 73.4 %, PDR 40.5 %, mean withdrawal time 7.8 minutes and 12.2 % of procedures with possible removal of a non-pedunculated lesion ≥ 20 mm reporting tattooing. Conclusions  Our findings clearly show areas in need of quality improvement and the importance of promoting quality monitoring throughout the colonoscopy procedure.

Increased Faecalibacterium abundance is associated with clinical improvement in patients receiving rifaximin treatment

Compositional and functional alterations of the gut microbiota are involved in the pathogenesis of several gastrointestinal diseases. Rifaximin is often used to induce disease remission due to its eubiotic effects on the gut microbiota. To investigate the correlation between changes in the gut microbiota composition and symptoms improvement in patients who present a clinical response to rifaximin treatment. Patients with ulcerative colitis (UC), Crohn's disease (CD), irritable bowel syndrome (IBS) and diverticular disease (DD) undergoing rifaximin treatment for clinical indication were enrolled in the study. Rifaximin was administered at the dose of 1,200 mg/day for 10 days. Faecal samples were collected at baseline and at the end of treatment; clinical improvement was assessed by Mayo score for UC, CD Activity Index (CDAI) for CD, IBS severity scoring system (IBS-SSS) for IBS and global symptomatic score (GSS) for DD. Twenty-five patients were included in the analysis and a clinical improvement was recorded for 10/25 (40%) of them. Microbial alpha diversity showed a slight increase in clinical responders (P=0.271), while it decreased in patients who did not improved (P=0.05). A significant post-treatment increase in Faecalibacterium abundance was observed in patients with a positive response (log₂FC 1.959, P=0.042). Roseburia abundance decreased in both groups, whereas Ruminococcus decreased only in patients who clinically improved. Clinical improvement consequent to rifaximin treatment is associated with an increase in Faecalibacterium abundance. Achieving a positive shift in the gut microbiota composition seems a key event to obtain a clinical benefit from treatment.

Management of hepatitis C infection before and after liver transplantation

Chronic hepatitis C (CHC) is the most common indication for liver transplantation (LT). Aggressive treatment of hepatitis C virus (HCV) infection before cirrhosis development or decompensation may reduce LT need and risk of HCV recurrence post-LT. Factors associated with increased HCV risk or severity of recurrence include older age, immunosuppression, HCV genotype 1 and high viral load at LT. HCV recurrence post-LT leads to accelerated liver disease and cirrhosis development with reduced graft and patient survival. Currently, interferon (IFN)-based regimens can be used in dual-agent regimens with ribavirin, in triple-agent antiviral strategies with direct-acting antivirals (e.g., protease inhibitors telaprevir or boceprevir), or before transplant in compensated patients to reduce HCV viral load to prevent or reduce the risk of post-LT recurrence and complications; they cannot be used in patients with decompensated cirrhosis. IFN-based regimens are used in less than half of HCV-infected patients waiting for LT due to extremely low efficacy and poor tolerability. However, antiviral therapy is indicated after LT in patients with histologically confirmed CHC despite tolerability issues. Improvements in side effect management have increased survival in patients achieving therapeutic targets. HCV treatment pre- and post-LT results in significant health care costs especially when lack of efficacy leads to disease worsening, although studies have shown sofosbuvir treatment before LT vs conventional post-LT dual antiviral is cost effective. The suboptimal efficacy and tolerability of IFN-based therapies, plus the significant economic burden, means the need for effective and well tolerated IFN-free anti-HCV therapy for pre- and post-LT remains high.

Dynamics of liver stiffness predicts complications in patients with HCV related cirrhosis treated with direct-acting antivirals

BACKGROUND

Direct acting antivirals(DAAs) are effective in reducing inflammatory ant fibrotic markers in patients with chronic hepatitis C virus(HCV) infection and to prevent liver-related complications. Two-dimensional shear wave elastography(2D-SWE) is an effective technique for the assessment of liver fibrosis.

AIM

To evaluate changes in liver stiffness(LS) in HCV cirrhotic patients undergoing DAA therapy and to identify non-invasive parameters that predict the occurrence of liver-related events.

METHODS

We enrolled 229 patients who received DAAs between January 2015 and October 2018. Ultrasound parameters and laboratory data were assessed before treatment and 24(T1) and 48(T2) weeks after end of treatment. Patients were followed up every 6 months to evaluate the development of HCC and other liver related complications. Multiple Cox regression analysis was used to determine parameters associated with the development of complications.

RESULTS

Model for End-stage Liver Disease(MELD) score(HR 1.16; CI 95% 1.01-1.33; p = 0.026) and a change in LS at T2(1-year Delta LS) < 20%(HR 2.98; CI 95% 1.01-8.1; p = 0.03) were independently associated with HCC risk. One-year Delta-LS <20% was independently associated with the development of ascites(HR 5.08; CI 95% 1.03 - 25.14; p = 0.04).

CONCLUSIONS

Dynamic changes of 2D-SWE-measured LS after DAA therapy may be a useful tool to identify patients who are at higher risk of liver related complications.