AGA Technical Review on the Evaluation of Functional Diarrhea and Diarrhea-Predominant Irritable Bowel Syndrome in Adults (IBS-D)

Critical appraisal of the SIBO hypothesis and breath testing: A clinical practice update endorsed by the European society of neurogastroenterology and motility (ESNM) and the American neurogastroenterology and motility society (ANMS)

BACKGROUND

There is compelling evidence that microbe-host interactions in the intestinal tract underlie many human disorders, including disorders of gut-brain interactions (previously termed functional bowel disorders), such as irritable bowel syndrome (IBS). Small intestinal bacterial overgrowth (SIBO) has been recognized for over a century in patients with predisposing conditions causing intestinal stasis, such as surgical alteration of the small bowel or chronic diseases, including scleroderma and is associated with diarrhea and signs of malabsorption. Over 20 years ago, it was hypothesized that increased numbers of small intestine bacteria might also account for symptoms in the absence of malabsorption in IBS and related disorders. This SIBO-IBS hypothesis stimulated significant research and helped focus the profession's attention on the importance of microbe-host interactions as a potential pathophysiological mechanism in IBS.

PURPOSE

However, after two decades, this hypothesis remains unproven. Moreover, it has led to serious unintended consequences, namely the widespread use of unreliable and unvalidated breath tests as a diagnostic test for SIBO and a resultant injudicious use of antibiotics. In this review, we examine why the SIBO hypothesis remains unproven and, given the unintended consequences, discuss why it is time to reject this hypothesis and its reliance on breath testing. We also examine recent IBS studies of bacterial communities in the GI tract, their composition and functions, and their interactions with the host. While these studies provide important insights to guide future research, they highlight the need for further mechanistic studies of microbe-host interactions in IBS patients before we can understand their possible role in diagnosis and treatment of patient with IBS and related disorders.

Serum Leucine-Rich α2 Glycoprotein Could Be a Useful Biomarker to Differentiate Patients with Normal Colonic Mucosa from Those with Inflammatory Bowel Disease or Other Forms of Colitis

(1) Background: Serum leucine-rich α2 glycoprotein (LRG) has been reported as a useful biomarker for monitoring disease activity in patients with inflammatory bowel disease (IBD). We investigated whether serum LRG can differentiate patients with normal colonic mucosa from those with IBD or other forms of colitis. (2) Methods: Patients with diarrhea, abdominal pain, or bloody stools were consecutively enrolled at their initial visit to our hospital. Serum LRG and C-reactive protein were measured, and a colonoscopy and histology were performed. (3) Results: We enrolled 317 patients (181 men, 136 women; median age: 51 years). Based on the endoscopic and histological criteria, 260 patients were diagnosed with ulcerative colitis (n = 134), Crohn's disease (n = 10), infectious colitis (n = 43), diverticular colitis (n = 17), or nonspecific colitis (n = 56). The remaining 57 patients were diagnosed with normal colonic mucosa including histology. The latter group's median LRG value (9.5 µg/mL, range: 5.8-13.5) was significantly lower than that of the other 260 patients (13.6 µg/mL, range: 6.8-62.7, p < 0.0001). The optimal LRG cut-off value of <10.4 µg/mL was derived from the receiver operating characteristic (ROC) curve, showing a 91% sensitivity and 77% specificity for identifying patients with normal colonic mucosa. (4) Conclusions: serum LRG values < 10.4 µg/mL could be a useful biomarker for predicting patients with normal colonic mucosa.

[Research status and prospects of probiotics in functional gastrointestinal disorders in infants and toddlers]

Functional gastrointestinal disorders (FGIDs) are common digestive system diseases in children, which can severely affect the growth and development of infants and toddlers. Probiotics therapy, as a relatively safe treatment method, have attracted the attention of researchers. However, their effectiveness in treating FGIDs in infants and toddlers is still unclear. This article reviews the mechanisms of probiotics in treating FGIDs in infants and toddlers, explores the reasons for the inconsistency in various research results, and aims to provide assistance for the clinical treatment of FGIDs in infants and toddlers and future research.

Protective effect of Pediococcus pentosaceus Li05 on diarrhea-predominant irritable bowel syndrome in rats

Pediococcus pentosaceus Li05 (Li05) has demonstrated potential benefits in various intestinal and liver diseases, but its potential and mechanisms in relieving diarrhea have not been understood. The objective of this research was to examine the effects and mechanisms of Li05 in rats with diarrhea-predominant irritable bowel syndrome (IBS-D) induced by wrap restrain stress (WRS) and 4% acetic acid. The results demonstrated that Li05 effectively alleviated weight loss, visceral sensitivity and diarrhea in rats with IBS-D. It also improved intestinal and systemic inflammation by reducing the levels of chemokines and proinflammatory cytokines (GRO/KC, RANTES, IL-1β, IL-7, and IL-18). The 5-hydroxytryptamine (5-HT) signaling pathway is involved in regulating excessive intestinal motility and secretion in IBS-D. Li05 effectively reduced the expression levels of the 5-HT3B receptor (5-HT3BR) (p < 0.01) in the intestine. Additionally, Li05 intervention had a regulatory effect on the gut composition, with a decrease in the abundance of [Ruminococcus] gauvreauii group, Dubosiella, Erysipelatoclostridium and Blautia, and an increase in the abundance of Alloprevotella, Anaerotruncus and Mucispirillum. Furthermore, Li05 induced significant changes in fatty acid and amino acid metabolism in the gut of rats with IBS-D. These findings indicate that Li05 exhibits an effective improvement in IBS-D symptoms by reducing inflammation and modulating gut microbiota and metabolism. Based on the above results, Li05 holds promise as a potential probiotic for managing IBS-D.

Journal of Clinical Gastroenterology Lectureship Dubai 2022 : Management of Irritable Bowel Syndrome With Diarrhea

Irritable bowel syndrome (IBS) with diarrhea (IBS-D) affects ~1% of the general population and is characterized by abdominal pain associated with diarrhea. IBS-D symptoms significantly impact the quality of life of patients. Major uncertainties remain regarding the optimal management of these patients. Several therapies have been investigated over the years for the treatment of IBS-D. In the initial management, commonly prescribed approaches with an effect on global IBS symptoms include a low Fermentable Oligo-, Di-, Mono-Saccharides and Polyols diet and probiotics, while antispasmodics are used for targeting abdominal pain and loperamide for diarrhea only. Additional therapeutic options for the relief of global IBS symptoms include rifaximin, 5-HT 3 antagonists, gut-directed psychological therapies, and eluxadoline, while tricyclic antidepressants can target abdominal pain and bile acid sequestrants diarrhea. Promising evidence exists for the use of mesalazine and fecal microbiota transplantation in IBS-D, although further evidence is needed for definitive conclusions regarding their efficacy.

Systematic review with meta-analysis: Diagnostic performance of faecal calprotectin in distinguishing inflammatory bowel disease from irritable bowel syndrome in adults

BACKGROUND

Symptoms of inflammatory bowel disease (IBD) often overlap with those of irritable bowel syndrome (IBS).

AIM

To evaluate the diagnostic performance of faecal calprotectin in distinguishing patients with IBD from those with IBS METHODS: We searched MEDLINE, Embase, Scopus, and Cochrane Library databases up to 1 January 2023. Studies were included if they assessed the diagnostic performance of faecal calprotectin in distinguishing IBD from IBS (defined according to the Rome criteria) using colonoscopy with histology or radiology as reference standard in adults. We calculated summary sensitivity and specificity and their 95% confidence intervals (CI) using a random-effect bivariate model. The risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies II.

RESULTS

We included 17 studies with a total of 1956 patients. The summary sensitivity was 85.8% (95% CI: 78.3-91), and the specificity was 91.7% (95% CI: 84.5-95.7). At a prevalence of IBD of 1%, the negative predictive value was 99.8%, while the positive predictive value was only 9%. Subgroup analyses showed a higher sensitivity in Western than in Eastern countries (88% vs 73%) and at a cut-off of ≤50 μg/g than at >50 μg/g (87% vs. 79%), with similar estimates of specificity. All studies were at "high" or "unclear" risk of bias.

CONCLUSIONS

Faecal calprotectin is a reliable test in distinguishing patients with IBD from those with IBS. Faecal calprotectin seems to have a better sensitivity in Western countries and at a cut-off of ≤50 μg/g.

Atractylodes macrocephala-Paeonia lactiflora Class Formula for the Treatment of Irritable Bowel Syndrome: A Systematic Review With Meta-Analysis and Trial Sequential Analysis

Previous meta-analyses suggested that Chinese herbal medicine (CHM) is effective for irritable bowel syndrome (IBS). Formulas with Atractylodes macrocephala and Paeonia lactiflora as the core pairs have been widely used by traditional Chinese medicine (TCM) practitioners for the treatment of IBS. We aimed to examine the efficacy and safety of the Atractylodes macrocephala-Paeonia lactiflora class formula (A-P CHM) for IBS through a meta-analysis and trial-sequential analysis (TSA). The protocol is registered in the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42023439087. We searched seven databases for data up to May 23, 2023. The primary outcome was global IBS symptom relief. The secondary outcomes included the IBS severity scoring system (IBS-SSS) score and treatment-related adverse events. The relative ratio (RR) (dichotomous variables), the standardized mean difference (SMD) (continuous variables), the number needed to treat (NNT), the number needed to harm (NNH), and the required information size (RIS) were calculated. Twenty-four eligible articles with 3,768 participants were included. Thirteen trials were at low risk of bias (RoB). Compared with placebo or Western medication, A-P CHM was associated with a significantly higher proportion of relief of global IBS symptoms. The TSA analysis verified the primary outcome. For the secondary outcome, the A-P CHM IBS-SSS score was lower than Western medication or placebo at the end of the treatment, which was further confirmed by the TSA analysis. We asserted that A-P CHM might be a potential candidate for patients with IBS, especially for IBS-D. It may provide a theoretical basis for future optimization of irritable bowel syndrome with diarrhea (IBS-D) herbal formulas. The overall certainty of the evidence was not high; more tightly designed randomized controlled trials (RCTs) are required in the future.

Methods of Determining Irritable Bowel Syndrome and Efficiency of Probiotics in Treatment: A Review

Background

Irritable bowel syndrome (IBS) is a prevalent lifestyle-associated ailment linked to the gut microbiota that significantly influences patients' quality of life. A notable correlation exists between Blastocystis infections and susceptibility to IBS, with infected individuals exhibiting an increased likelihood of developing the condition. Despite promising results from using probiotics to modulate the gut microbiota and manage IBS, the precise mechanisms and potential risks remain unclear.

Objective

This review aims to explore the therapeutic potential of probiotics, particularly Saccharomyces boulardii, in the management of IBS, highlighting the role of the gut microbiota and the gut-brain axis in IBS pathophysiology.

Methods

A comprehensive literature survey was conducted to examine the association between gut microbiota and IBS, the role of probiotics in managing IBS, the mechanisms of their action, and the potential risks associated with their long-term use. Additionally, this study addresses the influence of Blastocystis infections on IBS susceptibility and evaluates various ongoing clinical trials investigating probiotic use for IBS.

Results

S boulardii, a yeast species with probiotic properties, has demonstrated effectiveness in both the treatment and prophylaxis of IBS. Its administration is associated with a decrease in the proinflammatory cytokine interleukin 8 and an increase in the anti-inflammatory cytokine interleukin 10. Probiotics appear to function by inhibiting the growth of pathogenic microorganisms and regulating neurotransmitter activity, influencing the gut-brain axis. However, selecting appropriate probiotic strains and dosing regimens is crucial because of potential adverse effects, such as infections and allergic reactions.

Conclusions

Probiotics, specifically S boulardii, offer a promising avenue for IBS management by modulating gut microbiota. However, further research is necessary to delineate the precise mechanisms of action, optimal strains, dosing regimens for IBS treatment, and potential risks associated with long-term use. A comprehensive approach incorporating probiotics, a low-FODMAP diet, and cognitive-behavioral therapy may provide effective management of IBS symptoms.

Nutrition Considerations in Patients with Functional Diarrhea

PURPOSE

Functional diarrhea (FD) is a functional gastrointestinal disorder that affects a great percentage of the population and has damaging nutritional and psychological effects. In this review, evidence has been assessed and analyzed to provide nutrition considerations and recommendations for patients with functional diarrhea.

RECENT FINDINGS

The traditional irritable bowel syndrome (IBS) diet, the low FODMAP diet, and general recommendations for diarrhea have been established as interventions for FD. Additionally, nutrition outcomes such as vitamin and mineral deficiencies, hydration levels, and mental health status should be at the forefront of assessment. The importance of medical management of FD and IBS-D is established, with many existing evidence-based recommendations and approved medications available. Nutrition management of FD from a registered dietitian/dietitian nutritionist, from symptom control to dietary advice, is imperative. There are no "one-size-fits-all" approaches to nutrition management of FD, but there is promising literature that can shape personalized nutrition interventions from a registered dietitian.

Fecal Calprotectin for the Diagnosis and Management of Inflammatory Bowel Diseases

Calprotectin is a heterodimeric calcium- and zinc-binding protein mainly derived from the cytoplasm of neutrophils that has direct antimicrobial functions and a role in the regulation of the innate immune response. It can be found in various biological compartments, in particular, the stool, with concentrations related to the level of mucosal inflammation. The measurement of fecal calprotectin has thus been recognized as a useful surrogate marker to distinguish patients with inflammatory bowel disease from those with irritable bowel syndrome. Moreover, it allows the monitoring of intestinal inflammation with a high negative predictive value, making it possible to exclude the diagnosis of inflammatory bowel disease for symptomatic patients. It also shows high sensitivity for the identification of patients requiring additional examinations for diagnosis, such as colonoscopy, and the evaluation of therapeutic responses, providing evidence of relapse or mucosal healing, which can lead to the intensification or reduction of treatment. As calprotectin levels are a measure of mucosal inflammation, high fecal concentrations are also found in other diseases with an inflammatory component, such as infectious enteritis or colorectal cancer. Interpretation of the concentration must therefore always take into account the clinical history and symptoms specific to each patient.

Nutraceutical Combinational Therapy for Diarrhoea Control with Probiotic Beverages from Fermented Fruits, Vegetables and Cereals to Regain Lost Hydration, Nutrition and Gut Microbiota

This article deals with the condition of irregular bowel movements known as diarrhoea, its pathology, symptoms and aetiology. The information has been presented on causes of diarrhoea that include gut infections, food intolerances and allergies to certain ingredients, problems in the gastrointestinal tract like irritable bowel syndrome, inflammatory bowel disease and, the condition of dysbiosis which occurs due to long-term use of antibiotics, or other medicines, etc. Most cases of diarrhoea can be resolved without needing medical treatment; however, it is still important to avoid dehydration of the body and use some supplements to get necessary nutrients which are lost with frequent bowel movements before they can get absorbed and assimilated in the gastrointestinal tract. Probiotic products are reported as natural therapeutic agents, which can reduce the risk of diarrhoea in both adults and children. The intake of dietary fluid supplements in the form of fermented beverages containing probiotic strains could help in diarrhoea control. The patient would achieve benefits with the consumption of these functional beverages in three ways-by regaining lost fluids to the body, supplementing beneficial gut bacteria to restore diversity in gut microbiota, which was disturbed in the condition of diarrhoea as well as regaining a source of quick nutrition to recoup energy.

Irritable bowel syndrome - controversies in diagnosis and management

INTRODUCTION

The irritable bowel syndrome (IBS) is the best-recognized disorder of gut brain interactions (DGBI). However, it is controversial if the Rome IV criteria iteration for IBS diagnosis is fit for purpose.

AREAS COVERED

This review critically evaluates Rome IV criteria for diagnosis of IBS and addresses clinical considerations in IBS treatment and management, including dietary factors, biomarkers, disease mimics, symptom severity, and subtypes. The role of diet in IBS is critically reviewed along with the influence of the microbiota, including small intestinal bacterial overgrowth.

EXPERT OPINION

Emerging data suggest the Rome IV criteria are more suitable for identifying severe IBS and least useful for sub-diagnostic patients who are still likely to benefit from IBS treatment. Despite convincing evidence that IBS symptoms are diet-driven and often postprandial, a relationship to eating is not a Rome IV diagnostic criterion. Few IBS biomarkers have been identified, suggesting the syndrome is too heterogeneous to be measured by a single marker, and combined biomarker, clinical, dietary, and microbial profiling may be needed for objective characterization. With many organic diseases mimicking and overlapping with IBS, it's important clinicians are knowledgable about this to mitigate the risk of missing comorbid organic intestinal disease and to optimally treat IBS symptoms.

Fecal Calprotectin Concentrations in Cats with Chronic Enteropathies

Diagnosis of feline chronic inflammatory enteropathies (CIE) and the differentiation from small cell intestinal lymphoma (SCL) can be challenging. Intestinally expressed calprotectin (S100A8/A9 protein complex) appears to be part of the complex pathogenesis of feline chronic enteropathies (FCE). Fecal calprotectin is a non-invasive biomarker for intestinal inflammation in humans and dogs but has not yet been evaluated in cats. We hypothesized that fecal calprotectin (fCal) concentrations are increased in FCE, correlate with clinical and/or histologic disease severity, and distinguish cases of CIE from SCL. This case-control study included fecal samples and patient data from cats with CIE (n = 34), SCL (n = 17), other gastrointestinal (GI) diseases (n = 16), and cats with no clinical signs of GI disease (n = 32). fCal concentrations were measured using the immunoturbidimetric fCal turbo assay (Bühlmann Laboratories). Compared to healthy cats, fCal concentrations were significantly increased in CIE, SCL, and other diseases (all p < 0.0001), but were not different between these three groups (all p > 0.05), or between cats with extra-GI diseases and healthy controls. These findings suggest that fCal may have utility as a clinical biomarker for FCE but not for intestinal disease differentiation. It further supports the role of calprotectin in the pathogenesis of the spectrum of FCE, which includes CIE and SCL.

AGA Clinical Practice Guideline on the Role of Biomarkers for the Management of Ulcerative Colitis

BACKGROUND & AIMS

Biomarkers are used frequently for noninvasive monitoring and treatment decision making in the management of patients with ulcerative colitis (UC). This American Gastroenterological Association (AGA) guideline is intended to support practitioners in decisions about the use of biomarkers for the management of UC.

METHODS

A multidisciplinary panel of content experts and guideline methodologists used the Grading of Recommendations Assessment, Development and Evaluation framework to prioritize clinical questions, identify patient-centered outcomes, and conduct an evidence synthesis on the clinical performance of serum C-reactive protein (CRP), fecal calprotectin, and fecal lactoferrin as biomarkers of disease activity in patients with established UC in symptomatic remission or with active symptoms. The guideline panel used the Evidence-to-Decision framework to develop recommendations for the use of biomarkers for monitoring and management of UC and provided implementation considerations for clinical practice.

RESULTS

The guideline panel made 7 conditional recommendations. In patients with UC in symptomatic remission, the panel suggests the use of a biomarker- and symptom-based monitoring strategy over a symptom-based monitoring strategy. For patients in symptomatic remission, the panel suggests using fecal calprotectin <150 μg/g, normal fecal lactoferrin, and/or normal CRP to rule out active inflammation and avoid routine endoscopic assessment of disease. In patients with UC with moderate to severe symptoms, the panel suggests using fecal calprotectin >150 μg/g, elevated fecal lactoferrin, or elevated CRP to inform treatment decisions and avoid routine endoscopic assessment of disease. However, in patients in symptomatic remission but elevated biomarkers, and in patients with moderate to severe symptoms with normal biomarkers, the panel suggests endoscopic assessment of disease to inform treatment decisions. In patients with UC with mild symptoms, the panel suggests endoscopic assessment of disease activity to inform treatment decisions. The panel identified the use of a biomarker-based monitoring strategy over an endoscopy-based monitoring strategy as a knowledge gap. The panel also proposed key implementation considerations for optimal use of biomarkers, and identified areas for future research.

CONCLUSIONS

In patients with UC, noninvasive biomarkers, including fecal calprotectin, fecal lactoferrin, and serum CRP can inform disease monitoring and management.

Fecal Calprotectin Elevations Associated with Food Intolerance/Malabsorption Are Significantly Reduced with Targeted Diets

Inflammatory bowel disease (IBD) involves two clinically defined entities, namely Crohn's disease and ulcerative colitis. Fecal calprotectin (FCAL) is used as a marker to distinguish between organic IBD and functional bowel disease in disorders of the irritable bowel syndrome (IBS) spectrum. Food components may affect digestion and cause functional abdominal disorders of the IBS spectrum. In this retrospective study, we report on FCAL testing to search for IBD in 228 patients with disorders of the IBS spectrum caused by food intolerances/malabsorption. Included were patients with fructose malabsorption (FM), histamine intolerance (HIT), lactose intolerance (LIT), and H. pylori infection. We found elevated FCAL values in 39 (17.1%) of 228 IBS patients with food intolerance/malabsorption and H. pylori infection. Within these, fourteen patients were lactose intolerant, three showed fructose malabsorption, and six had histamine intolerance. The others had combinations of the above conditions: five patients had LIT and HIT, two patients had LIT and FM, and four had LIT and H. pylori. In addition, there were individual patients with other double or triple combinations. In addition to LIT, IBD was suspected in two patients due to continuously elevated FCAL, and then found via histologic evaluation of biopsies taken during colonoscopy. One patient with elevated FCAL had sprue-like enteropathy caused by the angiotensin receptor-1 antagonist candesartan. When screening for study subjects concluded, 16 (41%) of 39 patients with initially elevated FCAL agreed to voluntarily control FCAL measurements, although symptom-free and -reduced, following the diagnosis of intolerance/malabsorption and/or H. pylori infection. After the initiation of a diet individualized to the symptomatology and eradication therapy (when H. pylori was detected), FCAL values were significantly lowered or reduced to be within the normal range.

Choosing which in-hospital laboratory tests to target for intervention: a scoping review

INTRODUCTION

Some laboratory testing practices may be of low value, leading to wasted resources and potential patient harm. Our scoping review investigated factors and processes that developers report using to inform decisions about what tests to target for practice improvement.

METHODS

We searched Medline on May 30th, 2019 and June 28th, 2021 and included guidelines, recommendation statements, or empirical studies related to test ordering practices. Studies were included if they were conducted in a tertiary care setting, reported making a choice about a specific test requiring intervention, and reported at least one factor informing that choice. We extracted descriptive details, tests chosen, processes used to make the choice, and factors guiding test choice.

RESULTS

From 114 eligible studies, we identified 30 factors related to test choice including clinical value, cost, prevalence of test, quality of test, and actionability of test results. We identified nine different processes used to inform decisions regarding where to spend intervention resources.

CONCLUSIONS

Intervention developers face difficult choices when deciding where to put scarce resources intended to improve test utilization. Factors and processes identified here can be used to inform a framework to help intervention developers make choices relevant to improving testing practices.

Volatile organic compounds as potential biomarkers of irritable bowel syndrome: A systematic review

BACKGROUND

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease characterized by intermittent abdominal pain with altered bowel habits. Due to the condition's chronicity, patients suffer from poor quality of life, while the healthcare burden continues to grow. There is currently no reliable biomarker for the diagnosis of IBS, and the current approach depends on ruling-out organic diseases such as inflammatory bowel disease (IBD) and colorectal cancer by markers of inflammation like fecal calprotectin and C-reactive protein, or invasive procedures like a colonoscopy. Volatile organic compounds (VOCs) are growing in popularity as a biomarker due to its accuracy and ease of use.

PURPOSE

This systematic review of Medline and Cochrane's databases aimed to identify VOCs in the diagnosis of IBS. 57% of the studies proved that VOCs could identify IBS patients from healthy controls with AUC ranging from 0.83 to 0.99. Studies that distinguished IBS from IBD patients had slightly higher AUC of 0.87-0.98. Combining VOC into panels allowed the creation of discriminative algorithms. Though current research is limited by areas of heterogeneity in VOC sampling and small sample sizes, our review shows that VOC analysis has the potential to be a noninvasive point-of-care test that differentiates IBS from other organic gastrointestinal diseases.

iSTART-II: An Update on the i Support Therapy-Access to Rapid Treatment (iSTART) Approach for Patient-Centered Therapy in Mild-to-Moderate Ulcerative Colitis

The i Support Therapy-Access to Rapid Treatment (iSTART) was an initiative to improve patient-centered management in mild-to-moderate ulcerative colitis (UC). Our aim was to update the iSTART recommendations in order to include fecal calprotectin (FC) in the monitoring of patients with UC and improve their management. Twelve physicians from nine countries worldwide attended a virtual international consensus meeting on 4 May 2022. Data from three systematic reviews were analyzed, and a new systematic review investigating all studies reporting measurement of FC at home was conducted. Based on literature evidence, statements were formulated, discussed, and approved by voting. Statements were considered approved if at least 75% of participants agreed with a proposed statement. Fourteen statements were approved. Based on this consensus, FC measurement should be routinely performed for monitoring patients with mild-to-moderate UC to identify disease relapses early and initiate an appropriate treatment. Further studies are needed to assess whether self-monitoring of FC is associated with better disease control and improved patients' quality of life.

Italian guidelines for the management of irritable bowel syndrome: Joint Consensus from the Italian Societies of: Gastroenterology and Endoscopy (SIGE), Neurogastroenterology and Motility (SINGEM), Hospital Gastroenterologists and Endoscopists (AIGO), Digestive Endoscopy (SIED), General Medicine (SIMG), Gastroenterology, Hepatology and Pediatric Nutrition (SIGENP) and Pediatrics (SIP)

The irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction. IBS is still associated with areas of uncertainties, especially regarding the optimal diagnostic work-up and the more appropriate management. Experts from 7 Italian Societies conducted a Delphi consensus with literature summary and voting process on 27 statements. Recommendations and quality of evidence were evaluated using the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus was defined as >80% agreement and reached for all statements. In terms of diagnosis, the consensus supports a positive diagnostic strategy with a symptom-based approach, including the psychological comorbidities assessment and the exclusion of alarm symptoms, together with the digital rectal examination, full blood count, C-reactive protein, serology for coeliac disease, and fecal calprotectin assessment. Colonoscopy should be recommended in patients with alarm features. Regarding treatment, the consensus strongly supports a dietary approach for patients with IBS, the use of soluble fiber, secretagogues, tricyclic antidepressants, psychologically directed therapies and, only in specific IBS subtypes, rifaximin. A conditional recommendation was achieved for probiotics, polyethylene glycol, antispasmodics, selective serotonin reuptake inhibitors and, only in specific IBS subtypes, 5-HT3 antagonists, 5-HT4 agonists, bile acid sequestrants.

Multi-omics for biomarker approaches in the diagnostic evaluation and management of abdominal pain and irritable bowel syndrome: what lies ahead

Reliable biomarkers for common disorders of gut-brain interaction characterized by abdominal pain, including irritable bowel syndrome (IBS), are critically needed to enhance care and develop individualized therapies. The dynamic and heterogeneous nature of the pathophysiological mechanisms that underlie visceral hypersensitivity have challenged successful biomarker development. Consequently, effective therapies for pain in IBS are lacking. However, recent advances in modern omics technologies offer new opportunities to acquire deep biological insights into mechanisms of pain and nociception. Newer methods for large-scale data integration of complementary omics approaches have further expanded our ability to build a holistic understanding of complex biological networks and their co-contributions to abdominal pain. Here, we review the mechanisms of visceral hypersensitivity, focusing on IBS. We discuss candidate biomarkers for pain in IBS identified through single omics studies and summarize emerging multi-omics approaches for developing novel biomarkers that may transform clinical care for patients with IBS and abdominal pain.

Is mastocytic colitis a specific clinical-pathological entity?

The number of intestinal mast cells (MC) is increased in several types of colitis, but the mucosa of patients with chronic non-bloody diarrhea has not been studied. The current study sought to determine the relationship between MC counts and degranulation and the severity of symptoms in patients with chronic loose stools. Following a negative laboratory workup for the most common causes of chronic diarrhea, patients with chronic non-bloody loose stools were included in the study. Patients with macroscopic evidence of inflammation or organic disease were excluded after endoscopy with biopsies. Biopsies from the 179 patients in the study were stained with hematoxylin and eosin and anti-CD117 c-kit antibodies. Immunohistochemistry was used to assess the degree of MC degranulation. Out of the 179 patients, 128 had normal histologic findings suggestive of irritable bowel syndrome and were used as controls. Twenty-four presented with abnormally high MC counts (≥40 MC x HPF), 23 with ≥20 intraepithelial lymphocytes x HPF suggesting lymphocytic colitis, and 4 had both (≥40 MC and ≥20 intraepithelial lymphocytes x HPF). In the patients with high MC counts, figures were significantly higher in the right colon versus the left colon (p=0.016), but degranulation did not differ in the right versus the left colon (p=0.125). No age or sex-related difference was observed (p=0.527 and p=0.859 respectively). The prevalence of abdominal pain and bloating did not differ in the three groups (p=0.959 and p=0.140, respectively). Patients with lymphocytic colitis (p=0.008) and those with high MC counts (p=0.025) had significantly higher evacuation rates compared to controls. There was no difference between these two groups (p=0.831). Mast cell degranulation was not associated with the number of evacuations, abdominal pain, or bloating (p=0.51; p=0.41; p=0.42, respectively). The finding that a significantly higher number of evacuations was linked to increased MC in the colonic mucosa of a subset of patients with otherwise normal laboratory and endoscopic findings suggests that "mastocytic colitis" may be a new clinical-pathological entity responsible for chronic non-bloody diarrhea. Prospective studies with a larger number of patients, as well as endoscopic and histological follow-up, are needed to confirm this hypothesis.

A Randomized, Double-Blind, Placebo-Controlled Trial to Evaluate the Effects of Multi-Strain Synbiotic in Patients with Functional Diarrhea and High Fecal Calprotectin Levels: A Pilot Study

Synbiotics, including probiotics and prebiotics, are useful for patients with functional bowel disorders. However, which synbiotics are beneficial for patients with which diseases, especially those with functional diarrhea (FDr) with high fecal calprotectin levels, is currently unknown. FDr is an extension of irritable bowel syndrome with diarrhea (IBS-D). Although fewer studies have been conducted on FDr compared to IBS-D, its importance is increasing as its prevalence increases. The aim of this study was to evaluate the effects of a synbiotic containing a mixture of Lactobacillus and Bifidobacterium and its substrate, fructooligosaccharide, on bowel symptoms, fecal calprotectin levels, fecal microbiota, and safety in FDr patients with high fecal calprotectin levels. Forty patients were randomly assigned to either a synbiotic group or a placebo group. A total of 20 subjects in the synbiotic group and 19 subjects in the placebo group completed the study (8 weeks). Changes in FDr symptoms, fecal calprotectin levels, and gut microbiota were assessed during the intervention period. At 4 and 8 weeks, the number of bowel movements tended to increase in the synbiotic group, with a significant increase in the number of formed stools rather than loose stools (p < 0.05). Bowel movement satisfaction was significantly increased in the synbiotic group, but not in the placebo group. Intestinal flora analysis revealed that Lactobacillales at the order level was increased only in the synbiotic group at the end of the intervention. In contrast, at week 8 of the intervention, log-transformed fecal calprotectin levels were significantly decreased in the synbiotic group, although the change was not significantly different from that of the placebo group. These findings suggest that the intake of a multi-strain-containing synbiotic for 8 weeks could improve gut symptoms and the intestinal microenvironment of FDr patients with high fecal calprotectin levels.

SeHCAT (tauroselcholic [75selenium] acid) for the investigation of bile acid diarrhoea in adults: a systematic review and cost-effectiveness analysis

Background

Tauroselcholic [75selenium] acid (SeHCAT™) (GE Healthcare, Chicago, IL, USA) is a radiopharmaceutical that may be useful in diagnosing bile acid diarrhoea.

Objectives

To assess the clinical effectiveness and cost-effectiveness of SeHCAT for the investigation of adults with chronic unexplained diarrhoea, diarrhoea-predominant irritable bowel syndrome or functional diarrhoea (suspected primary bile acid diarrhoea), and adults with chronic diarrhoea and Crohn’s disease who have not undergone ileal resection (suspected secondary bile acid diarrhoea).

Methods

Sixteen databases were searched to November 2020. The review process included measures to minimise error and bias. Results were summarised by primary or secondary bile acid diarrhoea and study quality was considered. The cost-effectiveness analysis combined a short-term (6-month) decision-analytic model (diagnosis and initial treatment response) and a lifetime Markov model comprising three health states (diarrhoea, no diarrhoea and death), with transitions determined by probabilities of response to treatment. Analyses were conducted from an NHS and Personal Social Services perspective.

Results

Twenty-four studies were included in this review. Of these, 21 were observational studies, reporting some outcome data for patients treated with bile acid sequestrants, and in which only patients with a positive SeHCAT test were offered bile acid sequestrants. The median rate of response to bile acid sequestrants, among patients with a 7-day SeHCAT retention value of ≤ 15%, was 68% (range 38–86%) (eight studies). The estimated sensitivity of SeHCAT (≤ 15% threshold) to predict positive response to colestyramine was 100% (95% confidence interval 54.1% to 100%) and the specificity estimate was 91.2% (95% confidence interval 76.3% to 98.1%) (one study). The median proportion of treated patients who were intolerant/discontinued bile acid sequestrants was 15% (range 4–27%) (eight studies). There was insufficient information to determine whether or not intolerance varied between colestyramine, colestipol and colesevelam. For both populations, the SeHCAT 15% (i.e. a SeHCAT retention value of ≤ 15%) strategy dominated other strategies or resulted in incremental cost-effectiveness ratios of < £20,000–30,000 per quality-adjusted life-year gained. For the suspected primary bile acid diarrhoea population, SeHCAT 15% was the strategy most likely to be cost-effective: 67% and 73% probability at threshold incremental cost-effectiveness ratios of £20,000 and £30,000 per quality-adjusted life-year gained, respectively. For the Crohn’s disease population, these probabilities were 89% and 92% at £20,000 and £30,000 per quality-adjusted life-year gained, respectively. Cost-effectiveness was mostly led by treatment response. SeHCAT 15% was the strategy with the highest response rate in the majority of scenarios explored.

Limitations and conclusions

There is a lack of evidence linking the use of SeHCAT testing to patient-relevant outcomes. The optimal SeHCAT threshold, to define bile acid diarrhoea and select patients for treatment with bile acid sequestrants, is uncertain. It is unclear whether or not patients with ‘borderline’ or ‘equivocal’ 7-day SeHCAT retention values (e.g. between 10% and 15%) and patients with values of > 15% could benefit from treatment with bile acid sequestrants. Although the results of the economic evaluation conducted for both populations indicated that the SeHCAT 15% strategy dominated the other two strategies or resulted in incremental cost-effectiveness ratios that were lower than the common thresholds of £20,000 or £30,000 per quality-adjusted life-year gained, the paucity and poor quality of evidence mean that uncertainty is high.

Future work

The optimum study design would be a multiarm randomised controlled trial, in which participants meeting the inclusion criteria are randomised to receive colestyramine, colestipol, colesevelam or placebo, and all participants receive SeHCAT testing.

Study registration

This study is registered as PROSPERO CRD42020223877.

Funding

This project was funded by the National Institute for Health and Care Research (IHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 26, No. 45. See the NIHR Journals Library website for further project information.

Ameliorative effect and mechanism of Si-Ni-San on chronic stress-induced diarrhea-irritable bowel syndrome in rats

Background: Chronic stress-induced diarrhea is a common clinical condition, characterized by an abnormal bowel movement and loose stools, which lacks effective treatment in the clinic. Si-Ni-San (SNS) is a compound traditional Chinese medicine extensively used in China for stress-related diarrhea. However, the mechanism is unclear.

Methods: Male Wistar rats (200 ± 20 g) were placed in a restraint cylinder and fixed horizontally for 3 h once daily for 21 consecutive days to establish a chronic restraint stress (CRS) rat model. SNS (0.6944 g/kg or 1.3888 g/kg) was given by gavage 1 h before the restraint once daily for 21 consecutive days. We examined the fecal score, dopamine β hydroxylase (DβH), and c-fos expression in locus coeruleus, norepinephrine (NE) content in ileum and plasma, expression of α1 adrenergic receptors, MLCK, MLC, and p-MLC in the colon and mesenteric arteries, contraction of isolated mesenteric arteries, The expression of subunit δ of ATP synthase (ATP5D) in intestinal tissues, ATP, ADP, and AMP content in the ileum and colon, occludin expression between ileum epithelial cells, the number of enterochromaffin cells (ECs) and mast cells (MCs) in the ileum, and 5-hydroxytryptamine (5-HT) content in the ileum and plasma.

Results: After SNS treatment, the fecal score was improved. The increased expression of DβH and c-fos in locus coeruleus was inhibited. SNS suppressed the increased NE content in the ileum and plasma, down-regulated α1 adrenergic receptors in mesenteric arteries and MLCK, MLC, p-MLC in the colon and mesenteric arteries, and inhibited the contraction of mesenteric arteries. SNS also increased the ATP content in the ileum and colon, inhibited low expression of ATP5D in intestinal tissues, inhibited the decrease of ATP/ADP in the ileum and ATP/AMP in the colon, and up-regulated the occludin expression between ileum epithelial cells. In addition, SNS inhibited the increase of ECs and MCs in the ileum and the increase of 5-HT content in the ileum and plasma.

Conclusion: This study demonstrated that SNS could improve CRS-induced abnormal feces in rats. This effect was related to the inhibition of CRS-induced increased expression of DβH and c-fos in the locus coeruleus, NE content in the ileum and plasma, and the contraction of isolated mesenteric arteries; inhibition of energy metabolism abnormality and decreased occludin expression; inhibition of increased ECs and MCs in the ileum, and 5-HT content in the ileum and plasma.

AGA Clinical Practice Guideline on the Pharmacological Management of Irritable Bowel Syndrome With Diarrhea

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder associated with significant disease burden. This American Gastroenterological Association Guideline is intended to support practitioners in decisions about the use of medications for the pharmacological management of IBS with predominant diarrhea (IBS-D) and is an update of a prior technical review and guideline.

METHODS

The Grading of Recommendations Assessment, Development and Evaluation framework was used to assess evidence and make recommendations. The technical review panel prioritized clinical questions and outcomes according to their importance for clinicians and patients and conducted an evidence review of the following agents: eluxadoline, rifaximin, alosetron, loperamide, tricyclic antidepressants, selective serotonin reuptake inhibitors, and antispasmodics. The guideline panel reviewed the evidence and used the Evidence-to-Decision Framework to develop recommendations.

CONCLUSIONS

The panel agreed on 8 recommendations for the management of patients with IBS-D. The panel made conditional recommendations for eluxadoline, rifaximin, alosetron, (moderate certainty), loperamide (very low certainty), tricyclic antidepressants, and anstispasmodics (low certainty). The panel made a conditional recommendation against the use of selective serotonin reuptake inhibitors (low certainty).

Functional bowel disorders with diarrhoea: Clinical guidelines of the United European Gastroenterology and European Society for Neurogastroenterology and Motility

Irritable bowel syndrome with diarrhoea (IBS‐D) and functional diarrhoea (FDr) are the two major functional bowel disorders characterized by diarrhoea. In spite of their high prevalence, IBS‐D and FDr are associated with major uncertainties, especially regarding their optimal diagnostic work‐up and management. A Delphi consensus was performed with experts from 10 European countries who conducted a literature summary and voting process on 31 statements. Quality of evidence was evaluated using the grading of recommendations, assessment, development, and evaluation criteria. Consensus (defined as >80% agreement) was reached for all the statements. The panel agreed with the potential overlapping of IBS‐D and FDr. In terms of diagnosis, the consensus supports a symptom‐based approach also with the exclusion of alarm symptoms, recommending the evaluation of full blood count, C‐reactive protein, serology for coeliac disease, and faecal calprotectin, and consideration of diagnosing bile acid diarrhoea. Colonoscopy with random biopsies in both the right and left colon is recommended in patients older than 50 years and in presence of alarm features. Regarding treatment, a strong consensus was achieved for the use of a diet low fermentable oligo‐, di‐, monosaccharides and polyols, gut‐directed psychological therapies, rifaximin, loperamide, and eluxadoline. A weak or conditional recommendation was achieved for antispasmodics, probiotics, tryciclic antidepressants, bile acid sequestrants, 5‐hydroxytryptamine‐3 antagonists (i.e. alosetron, ondansetron, or ramosetron). A multinational group of European experts summarized the current state of consensus on the definition, diagnosis, and management of IBS‐D and FDr.

Screening for gastrointestinal and pancreatic diseases

Diagnosis of chronic gastrointestinal and pancreatic diseases is challenging because patients generally present with nonspecific symptoms, such as abdominal pain and chronic diarrhea, some of which can last for many years. Although stool assays are more sensitive than serum assays, the former has unique limitations that healthcare providers should be aware of. One algorithm to screen for chronic gastrointestinal and pancreatic issues is to perform stool testing to assess inflammatory, watery (osmotic) and malabsorptive conditions. This chapter will discuss several stool-based screening tests, the major disorders they screen for and clinical performance. Sections on assay and sample limitations are also included. Stool testing can provide valuable diagnostic, prognostic and treatment response information if both the laboratory and clinician understand the benefits and limitations of these assays.

Dual Inhibition of Phosphodiesterase and Ca++ Channels Explains the Medicinal Use of Balanites aegyptiaca (L.) in Hyperactive Gut Disorders

The present study attempted to evaluate and rationalize the medicinal use of the methanolic extract of the fruits of Balanites aegyptiaca (B. aegyptiaca) in the treatment of hyperactive gut disorders. The in vivo, castor oil-induced diarrhea model in mice was followed to test its antidiarrheal effect. To test the antispasmodic effect and to explore its pharmacodynamic details, isolated small intestines (ileum) obtained from rats were selected to provide physiological conditions for the ex vivo assays. In the in vivo assays, the orally administered extract of B. aegyptiaca protected mice from diarrheal drops with resultant percent inhibitions of 40% and 80% at the respective doses of 200 mg/kg and 400 mg/kg, while the highest protection (100%) was observed with a positive control drug, loperamide, at 10 mg/kg. In the ileum, B. aegyptiaca produced an antispasmodic effect in a concentration-dependent manner by inhibiting the carbachol (CCh; 1 µM) and high K⁺ (80 mM)-evoked spasms with resultant EC₅₀ values of 1.44 mg/mL (1.08–1.78) and 1.27 mg/mL (0.98–1.66), respectively. Papaverine, a known phosphodiesterase enzyme (PDE) inhibitor and blocker of Ca⁺⁺ channels (CCB), also inhibited both CCh and high K⁺ induced contractions at comparable EC₅₀ values of 8.72 µM (7.92–9.24) and 8.14 µM (7.62–8.84), respectively. Contrary to the extract and papaverine, verapamil showed distinctly higher potency in regard to inhibiting high K⁺, compared to CCh-evoked spasms that had EC₅₀ values of 0.16 µM (0.13–0.261) and 2.54 µM (2.28–2.92), respectively. The inhibitory effects of B. aegyptiaca on PDE were further confirmed when the pre-incubated extract shifted the isoprenaline-mediated relaxation curves (CRCs) towards the left, similar to papaverine, whereas the CCB-like effect was confirmed when the pre-incubated tissues with B. aegyptiaca caused deflection in the Ca⁺⁺ CRCs towards the right, constructed in Ca⁺⁺ free medium with suppression of the maximum response. Thus, this study provides detailed, mechanistic support for the medicinal use of B. aegyptiaca in the treatment of hyperactive gut disorders.

Core indicators of an evaluation and guidance system for quality of care in inflammatory bowel disease centers: A critical review

The mission of the IBD Quality Care Evaluation Center (IBDQCC) is to establish indicators of quality of care (QoC), certify IBD units to generate a network of IBD quality care, and eventually improve the national level of IBD healthcare. The final list of 28 core and 13 secondary IBD QoC indicators suitable for the healthcare system in China were selected using a Delphi consensus methodology. Units that met all core indicators were qualified as "regional"; units that met all core indicators together with more than 50% of the secondary indicators received a rating of "excellence." Using the selected QoC core indicators for certifying IBD units, a network of IBD quality care units covering the majority of IBD patients in China was established.

FUNDING

This work was financially supported by Cultivation Funding for Clinical Scientific Research Innovation, Renji Hospital, School of Medicine, Shanghai Jiaotong University (RJPY-LX-004), National Natural Science Foundation of China (No. 81,770,545), Shanghai Science and Technology Innovation Initiative (21SQBS02302), and Cultivated Funding for Clinical Research Innovation, Renji Hospital, School of Medicine, Shanghai Jiaotong University (RJPY-LX-004).

Comparison of Next-Generation Assays for Fecal Calprotectin vs the PhiCal Assay

OBJECTIVES

To compare the PhiCal assay (CALPRO), the first US Food and Drug Administration-approved assay for fecal calprotectin, to 4 next-generation assays.

METHODS

Stool samples from 50 patients were selected, and relevant clinical information was collected. Comparisons were performed using the PhiCal, fCAL turbo (BÜHLMANN), LIAISON Calprotectin (DiaSorin), QUANTA Lite Calprotectin ELISA (Inova Diagnostics), and Calprotectin Chemiluminescence ELISA (ALPCO) assays.

RESULTS

All 4 assays had acceptable agreement with PhiCal when qualitatively categorizing results. Within the PhiCal reportable range of 16 to 1,250 μg/g, the DiaSorin, Inova Diagnostics, and ALPCO assays had Spearman correlation coefficients of 0.98, 0.97, and 0.95 and positive biases of 17%, 20%, and 15%, respectively. The BÜHLMANN assay ran approximately 2-fold higher than the PhiCal assay but had a correlation coefficient of 0.98, with similar result categorization.

CONCLUSIONS

Our results demonstrate good comparison between PhiCal and 4 next-generation assays. Laboratories performing fecal calprotectin assays may have compelling reasons to adopt next-generation fecal calprotectin testing, such as greater automation, a decreased number of replicates needed per test, and the use of stool-extraction devices. These benefits could decrease turnaround times and lower costs. Although the results of the assays correlated, they are not standardized. Laboratories adopting the newer assays will need to further investigate their performance through validation studies.

Is the Medium Still the Message? Culture-Independent Diagnosis of Gastrointestinal Infections

Infectious diarrhea is caused by a variety of pathogens, including viruses, bacteria, and parasitic organisms. Though the causative agent of diarrhea has historically been evaluated via stool cultures, recently, culture-independent diagnostic tests (CIDT) have been developed and utilized with increasing frequency. Current practice guidelines recommend their use as adjuncts to stool cultures for diagnosing acute and chronic diarrhea. The three principal CIDT are microscopy, enzyme-based immunoassays (EIAs), and molecular based polymerase chain reaction (PCR). This review explores the common causes of infectious diarrhea, the basics of stool culture, the diagnostic utility of these three culture-independent modalities, and the strengths and weaknesses of all currently available clinical techniques. It also outlines considerations for specific populations including returning travelers and those with inflammatory bowel disease.

Mechanism of QingHuaZhiXie Prescription Regulating TLR4-IECs Pathway in the Intervention of Diarrhea Predominant Irritable Bowel Syndrome

To investigate the effect and mechanism of QingHuaZhiXie prescription on diarrhea predominant irritable bowel syndrome (D-IBS), animal models of rats were used in this study. 48 rats were randomly divided into 6 groups, containing one control group, one animal model group (D-IBS group), and four drug intervention groups (low, medium, and high dosage of QingHuaZhiXie prescription and trimebutine maleate intervention group). Abdominal withdrawal reflex (AWR) and Bristol stool form scale were recorded; the expression levels of inflammatory factors (TNF-α and IFN-γ), pathway proteins TLR4, MyD88, NF-κB, and key proteins of tight junction between intestinal epithelial cells (IECs) were detected; the microstructure of intestinal mucosal was observed by hematoxylin and eosin (H&E) staining; MPO activity was detected with immunohistochemical analysis to reflect the inflammation of tissues. Results show that QingHuaZhiXie prescription reduced diarrhea index and intestinal hypersensitivity and intestinal tissue integrity after intervention. MPO activity in QingHuaZhiXie prescription-treated rats was significantly lower relative to their model group. The expression levels of inflammatory factors and TLR4/MyD88/NF-κB pathway proteins were repressed, and the protein levels of occludin and claudin-1 increased. Meanwhile, this study also found that the remission effect of QingHuaZhiXie prescription on D-IBS increased with its dosage increase. Hence, as a therapeutic prescription for D-IBS, QingHuaZhiXie prescription could relieve D-IBS symptoms through balancing the inflammatory factors expression by inhibiting the TLR4/MyD88/NF-κB pathway and maintaining the function and structure of IECs by improving the protein levels of JAM, occludin, claudin-1, and ZO-1.

Pre-and post-treatment evaluation of intestinal inflammation in Giardia and Blastocystis infected children: a community-based study

Giardia intestinalis and Blastocystis hominis cause frequent infections in children in developing countries. However, the role of intestinal inflammation in their pathogenesis is still poorly understood. Faecal calprotectin (FC) level is used as an indicator of intestinal inflammation and neutrophil migration in the intestinal tract. The present study aimed to evaluate intestinal inflammation by measuring FC level among children infected with either G. intestinalis or B. hominis before and after treatment. Stool samples were collected from 282 children inhabiting a rural area in Egypt and examined microscopically for intestinal parasites. FC level was estimated in a group of children infected with G. intestinalis (n = 12) or B. hominis (n = 12) before and 3 weeks after receiving nitazoxanide (200 mg twice daily for 3 days) and compared to a control group (n = 18) of parasite-free children. Cases of mixed infection were excluded. Nitazoxanide cure rate was 83% in both infections with a remarkable reduction of infection intensity in uncured children. The difference in FC levels between infected children and controls was not statistically significant. Also, the difference between the pre- and post-treatment estimations was not statistically significant. Elevated levels were observed before treatment in three children (two infected with G. intestinalis and one with B. hominis) who displayed normal post-treatment levels. Although G. intestinalis and B. hominis infections appear to cause no remarkable intestinal inflammation, they may induce abnormally elevated FC levels in a subset of children.

Making a Confident Diagnosis of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is among the most common diagnoses made by medical providers and its symptoms are common causes for health care consultation. IBS is characterized by abdominal pain associated with abnormal stool consistency and/or frequency and is widely considered a diagnosis of exclusion, despite abundant evidence contradicting such an approach. A positive diagnosis is achieved through application of symptom-based clinical criteria, careful history and physical examination, evaluation for alarm sign/symptoms, and judicious use of diagnostic testing. This article reviews the symptom-based criteria for IBS and utility of diagnostic tests commonly included in the evaluation of IBS symptoms.

Development of a Score to Predict Positive Colonic Histology in Chronic Diarrhea Assessed in Open-access Colonoscopy

GOALS

To evaluate the diagnostic yield of colonoscopy and esophagogastroduodenoscopy with biopsies and to identify predictors of positive colonic histology in patients with chronic diarrhea.

BACKGROUND

Colonoscopy with biopsies is performed in chronic diarrhea with negative initial work-up.

STUDY

We reviewed electronic medical records of 1022 consecutive patients with chronic diarrhea referred for a first colonoscopy (including 25% open-access referrals). Predictors of positive colonic histology were investigated using logistic regression.

RESULTS

Four hundred thirteen patients with macroscopically normal colon were divided into derivation (n=275) and validation (n=138) cohorts. All patients underwent colonoscopy; 369 had ileoscopy (biopsies in 43%), and 289 underwent esophagogastroduodenoscopy (duodenal biopsies in 93%). In patients with endoscopically normal colon, histology was positive in 13.3%: 10.6% microscopic colitis; 1.5% other colitides. Among 358 patients with negative histology, the recorded diagnoses were: 48% unexplained, 25% irritable bowel syndrome, 5.6% small intestinal bacterial overgrowth, and 4.7% bile acid diarrhea. The rates of diagnoses based on positive histologies were 4% for ileal and 5% for duodenal biopsies. Older age [odds ratio (OR)=1.05] was a positive predictor, whereas body mass index (OR=0.93) and duration of diarrhea (OR=0.98) were negative predictors of positive histology. A clinical diagnostic scoring system could correctly predict 41% to 54% of patients with normal colonic histology, with a false-negative rate of 0.8% to 2.6% and a negative predictive value of 95% to 98%.

CONCLUSIONS

Positive colonic biopsies were detected in <15% of patients with chronic diarrhea with normal colonoscopy; a clinical score correctly predicts likelihood of normal histology in about half the patients.

Approach to the adult patient with chronic diarrhea: A literature review

Chronic diarrhea is defined by symptoms lasting longer than 4 weeks. It is a common problem that affects up to 5% of the adult population. Different pathophysiologic mechanisms involve numerous causes, including drug side effects, postoperative anatomic and physiologic alterations, intestinal and colonic wall abnormalities, inflammatory or malabsorption causes, pancreatobiliary diseases, and functional or gut-brain axis disorders associated with dysbiosis or gastrointestinal motility alterations. Due to such a broad differential diagnosis, it is important to categorize chronic diarrhea into five main groups: drug side effect, postoperative, postinfectious, malabsorptive, inflammatory, and functional. The present review is a narrative analysis of the diagnostic approach, emphasizing key aspects of the clinical history, the utility of biomarkers (in breath, stool, urine, and serology) and malabsorption and motility tests, the role of radiologic and endoscopic studies, and the most common histologic findings. A diagnostic algorithm aimed at determining etiology and personalizing therapy is also proposed.

An Update on the Assessment and Management of Pediatric Abdominal Pain

Chronic abdominal pain is very common in children and adolescent and results in high personal and social costs. Most youth with chronic abdominal pain fulfill criteria for a functional abdominal pain disorder (FAPD) as defined by Rome criteria. These are complex conditions with a wide array of biological, psychological, and social factors contributing to the experience of pain. The purpose of the current review is to provide an overview of the pathophysiology of FAPDs and an up-to-date summary of the literature related to FAPDs in children and adolescents, with additional focus on several areas (eg, diet and probiotics) where patients and families frequently have questions or implement self-directed care. We also provide an approach to the assessment and treatment of pediatric FAPDs focusing on the robust literature regarding psychological interventions and much sparser literature regarding medication treatment.

Chinese Herbal Medicine for Irritable Bowel Syndrome: A Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

Purpose: Chinese herbal medicine (CHM) is an important complementary and alternative therapy for the management of irritable bowel syndrome (IBS). Previous meta-analyses suggested that CHM is effective for IBS; nonetheless, its effectiveness is inconclusive owing to repeated significance testing. We aimed to examine the efficacy and safety of CHM for IBS through a meta-analysis and trial sequential analysis (TSA).

Methods: We searched OVID Medline, Embase, Cochrane Central Register of Controlled Trials, and Web of Science from January 1, 1980, to September 20, 2020. The primary outcome was adequate relief of global IBS symptoms. The secondary outcomes included relief of abdominal pain and treatment-related adverse events. The relative ratio (RR) and required information size (RIS) were calculated for each outcome.

Results: Ten trials recruiting 2,501 participants were included. Seven (70%) trials were at low risk of bias (RoB). Compared with placebo, CHM was associated with a significantly higher proportion of adequate relief of global IBS symptoms [RR 1.76 (95% confidence interval (95%CI), 1.33–2.33); I² = 81.1%; p < 0.001]. The RIS was 1,083 for the primary outcome, and the accrued information size was 1,716. The analysis of the relief of abdominal pain (three trials with 916 participants) showed similar results compared with placebo [RR 1.85 (95%CI, 1.59–2.14); I² = 0%; p < 0.001; RIS = 197 participants]. CHM was associated with a higher proportion of adverse events compared with placebo [RR 1.51 (95%CI, 1.14–2); I² = 0%; p = 0.004].

Conclusion: CHM was effective in relieving IBS symptoms but caused a higher adverse event rate than placebo. TSA analysis confirmed the findings with sufficient information size.

Approach to the adult patient with chronic diarrhea: a literature review

Chronic diarrhea is defined by symptoms lasting longer than 4 weeks. It is a common problem that affects up to 5% of the adult population. Different pathophysiologic mechanisms involve numerous causes, including drug side effects, postoperative anatomic and physiologic alterations, intestinal and colonic wall abnormalities, inflammatory or malabsorption causes, pancreatobiliary diseases, and functional or gut-brain axis disorders associated with dysbiosis or gastrointestinal motility alterations. Due to such a broad differential diagnosis, it is important to categorize chronic diarrhea into five main groups: drug side effect, postoperative, postinfectious, malabsorptive, inflammatory, and functional. The present review is a narrative analysis of the diagnostic approach, emphasizing key aspects of the clinical history, the utility of biomarkers (in breath, stool, urine, and serology) and malabsorption and motility tests, the role of radiologic and endoscopic studies, and the most common histologic findings. A diagnostic algorithm aimed at determining etiology and personalizing therapy is also proposed.

International consensus on methodological issues in standardization of fecal calprotectin measurement in inflammatory bowel diseases

BACKGROUND

Fecal calprotectin (FC) is a non-invasive marker of gut inflammation which is frequently used to guide therapeutic decisions in patients with inflammatory bowel diseases (IBD). Each step of FC measurement can influence the results, leading to misinterpretations and potentially impacting the management of IBD patients. To date, there is high heterogeneity between FC measurements and no current method is universally accepted as a standard.

AIMS

Our aim was to provide clear position statementsabout the pre-analytical and the analytical phases of FC measurement to homogenize FC levels and to minimize variability and risk of misinterpretation through aninternational consensus.

MATERIALS & METHODS

Fourteen physicians with expertise in the field of IBD and FC from 11 countries attended a virtual international consensus meeting on July 17th, 2020. A systematic literature was conducted and the literature evidence was shared and discussedamong the participants. Statements were formulated, discussed, and voted. Statements were considered approved if all participants agreed.

RESULTS

Nine statements were formulated and approved. Based on the available evidence, quantitative tests should be preferred for measuring FC. Furthermore, FC measurement, if possible, should always be performed with the same method and factors influencing FC levels should be taken into account when interpreting the results.

DISCUSSION

FC has an increasingly important role in the management of patients with IBD. However, large multicenter studies should be conducted to define the reproducibility and to confirm the diagnostic accuracy of the available FC tests.

CONCLUSION

FC concentrations guide clinicians' treatment decisions. Our statements have a relevant impact in daily practice and could be applied in clinical trials to standardize FC measurement.

Is Celiac Disease Testing Necessary in Functional Abdominal Disorders? A Study in Predominantly Latino Children

BACKGROUND

Functional abdominal pain disorders (FAPDs) are among the most common causes of consultation in general pediatrics and pediatric gastroenterology. The Rome IV criteria recommend testing for celiac disease (CD) in children with irritable bowel syndrome-diarrhea (IBS-D) and leaves testing in cases of other FAPDs to the practitioner's discretion. These recommendations were based on a single study that showed a 4-fold increase of CD among patients with IBS in Italy. It is unclear if these findings can be extrapolated to other populations. Understanding whether those results are reproducible in areas with different racial/ethnic backgrounds can optimize patient care.

AIM

The aim of the study was to assess the prevalence of CD in a sample of children consulting for FAPDs to a tertiary care center in Miami.

METHODS

The charts of all pediatric patients consulting for FAPDs from January 2016 to November 2019 at the University of Miami were reviewed. Demographics, diagnosis, and CD testing for each child were analyzed.

RESULTS

One hundred eighty-one children with FAPDs and celiac testing were seen. Mean age of 12.89 years, girls 61.34%. 84 (46.40%) had a diagnosis of IBS and 97 (53.59%) had a diagnosis of other FAPD. One of 181 children with FAPDs (0/84 with IBS and 1/97 with other FAPDs) had positive CD serological testing and EGD confirmation.

CONCLUSIONS

Our study suggests that the prevalence of CD among children with FAPDs is similar to the community prevalence. This data questions the benefit of testing all children FAPDS (including IBS) for CD. Studies with larger sample size and various racial/ethnic makeup should be done to confirm our findings.

Management of irritable bowel syndrome with diarrhea: focus on eluxadoline

OBJECTIVE

We sought to summarize current recommendations for the diagnosis of diarrhea-predominant irritable bowel syndrome (IBS-D) and describe available management options, highlighting a newer US Food and Drug Administration (FDA)-approved agent, eluxadoline.

METHODS

Literature on IBS-D was assessed up to January 2020 using PubMed, with key search terms including "IBS-D diagnosis", "IBS-D management", and "eluxadoline".

RESULTS

IBS is a common gastrointestinal disorder affecting up to 14% of US adults and is particularly prevalent in women and those aged under 50. Symptoms include abdominal pain associated with altered bowel habits (i.e. diarrhea and/or constipation subtyped based on the predominant stool pattern). As IBS-D is challenging to manage with varying symptom severity, effective treatment requires a personalized management approach. Evidence-based therapeutic options endorsed by the American Gastroenterological Association and the American College of Gastroenterology can be used to effectively guide treatment. Dietary and lifestyle modifications, including adequate hydration, reducing caffeine and alcohol intake, and increasing soluble fiber intake may lead to symptom improvement. Over-the-counter medications such as loperamide are frequently recommended and may improve stool frequency and rectal urgency; however, for the outcome of abdominal pain, mixed results have been observed. Several off-label prescription medications are useful in IBS-D management, including tricyclic antidepressants, bile acid sequestrants, and antispasmodics. Three prescription medications have been approved by the FDA for IBS-D: alosetron, eluxadoline, and rifaximin.

CONCLUSIONS

IBS-D can be effectively managed in the primary care setting in the absence of alarm features. Benefits and risks of pharmacologic interventions should be weighed during treatment selection.

A positive diagnostic strategy is safe and saves endoscopies in patients with irritable bowel syndrome: A five-year follow-up of a randomized controlled trial

BACKGROUND

Previously, the diagnosis of irritable bowel syndrome (IBS) required exclusion of organic causes by extensive diagnostic testing. Newer guidelines recommend IBS as a positive diagnosis based on symptoms with limited testing. We investigated the long-term safety and impact on use of health resources of a positive diagnostic strategy compared to a strategy of exclusion in patients with symptoms compatible with IBS.

METHODS

In 2008-2010, primary care patients aged 18-50 years fulfilling the Rome III criteria for IBS without alarm signals were randomized to a positive diagnostic strategy (limited blood tests, n = 150) or a strategy of exclusion (extensive blood tests, fecal samples for intestinal parasites, and sigmoidoscopy with biopsies, n = 152). At five years, hospital-registered diagnoses and use of health resources including lower endoscopies were retrieved from national registries. Participants provided 5-year data on Rome III criteria for IBS, severity of symptoms, and quality of life.

KEY RESULTS

Baseline mean age was 31.4 (SD 9.1) years; 79% were female. No cases of celiac disease, and gastrointestinal or gynecological cancers were diagnosed within five years. Negligible and comparable numbers were diagnosed with inflammatory bowel disease, benign gynecological conditions, and upper GI conditions in the two groups. The positive diagnosis strategy carried a higher number of lower endoscopies from year 1 to 5 (23 patients versus 13 patients in the exclusion group), but overall saved endoscopies.

CONCLUSIONS & INFERENCES

A positive diagnosis of IBS was as safe as a diagnosis of exclusion in a five-year perspective and saved lower endoscopies; the study was registered at ClinicalTrials.gov numbers: NCT00659763/NCT01153295.

Shenling Baizhu Powder () Ameliorates Pi (Spleen)-Deficiency-Induced Functional Diarrhea in Rats

OBJECTIVE

To explore the mechanism of Pi (Spleen)-deficiency-induced functional diarrhea (FD) model rats treated by Shenling Baizhu Powder (, SBP).

METHODS

Thirty male Sprague-Dawley rats were randomly divided into 5 groups including control, model, low-, medium-, and high-dose SBP groups (SBPLDG, SBPMDG, SBPHDG), 6 rats in each group, respectively. Pi-deficiency-induced FD rats model was developed through Radix et Rhizoma Rhei gavage for 7 days. After modeling, the rats were treated with 3 doses of SBP [0.93, 1.86, and 3.72 g/(kg·d)], and the rats in the control and model groups were given pure water for 7 days. The diarrhea index was calculated. On the 7th and 14th days, the traveled distance of rat was measured by the open field test. Serum D-xylose content was determined by the phloroglucinol method and interleukin (IL)-10 and IL-17 levels were measured using an enzyme-linked immunosorbent assay kit. The content of Treg cells was determined by flow cytometry.

RESULTS

Compared with the control group, the diarrhea index and IL-17 level in the model group were significantly higher and the total exercise distance and D-xylose content significantly decreased (P>0.05). The expression of IL-10 in the SBPHDG group was significantly up-regulated, and serum D-xylose level and Treg cells increased significantly compared with the model group (P>0.05).

CONCLUSION

High-dose SBP exhibited ameliorating effects against Pi-deficiency induced FD, which might be attributed to its modulations on intestinal absorption function as well as adaptive immunity in mesenteric lymph nodes of rat.

Prevalence of biliary acid malabsorption in patients with chronic diarrhoea of functional characteristics: a prospective study

Background

Bile acid malabsorption occurs in up to one third of patients with chronic diarrhoea of functional characteristics. The gold standard test for its diagnosis is the ⁷⁵Selenium homocholic acid taurine (⁷⁵SeHCAT) test. The aim of this work is to confirm previous data suggesting that bile acid malabsorption, diagnosed by ⁷⁵Se-HCAT test, is the underlying cause of diarrhoea in a significant proportion of patients previously diagnosed with a functional disorder. In addition, we have analysed the clinical response of bile acid sequestrants in those patients with a bile acid diarrhoea diagnosis.

Methods

This is a prospective, single-centre study including consecutive adult patients diagnosed with chronic diarrhoea of unknown origin and with functional characteristics; systematic rule out of common causes of chronic diarrhoea was performed before bile acid malabsorption evaluation by ⁷⁵SeHCAT scanning. A retention percentage less than 10% was considered positive. Clinical response to cholestyramine was further evaluated in those patients with a positive diagnosis of bile acid diarrhoea

Results

38 patients (20 male, mean age 37.5 years) were finally included. Twenty (52.6%) patients included had a positive ⁷⁵SeHCAT test. Median body mass index was significantly higher in those patients. We did not find significant differences in other clinical or biochemical variables ⁷⁵SeHCAT-positive and ⁷⁵SeHCAT-negative groups. Only 6 of 17 (35.3%) patients responded to cholestyramine treatment; 10 patients did not have response or withdraw the drug due to adverse events. Logistic regression analysis showed that none of the included variables was a predictor of clinical response to cholestyramine.

Conclusions

Bile acid malabsorption occurs in a high proportion of patients suffering from chronic diarrhoea with functional characteristics. Systematic investigation of bile acid malabsorption should be included in the diagnostic algorithms of patients with chronic watery diarrhoea in the routine clinical practice. Absence of response to cholestyramine does not rule out bile acid diarrhoea.

The patient with irritable bowel syndrome-type symptoms: when to investigate and how?

PURPOSE OF REVIEW

Irritable bowel syndrome (IBS) is a very common disorder whose clinical presentation varies considerably between patients as well as within the same individual over time. Many of its symptoms, such as pain, diarrhea, constipation and bloating, may be manifestations of a host of other gastrointestinal diseases; some accompanied by increased mortality. This presents the clinician with a real dilemma: how to sensibly investigate the patient in which one suspects IBS but there is a nagging doubt that 'it could be something else'? Could one miss 'something serious'? This short review attempts to provide both an evidence-based response to these vexing questions and a practical guide to detecting alternative diagnoses in the subject with IBS-type symptoms.

RECENT FINDINGS

Clinical features, patient demographics and the clinical context can help to significantly narrow the differential diagnosis of the individual with IBS-type symptoms and may permit a positive diagnosis of IBS. The advent of noninvasive serological and stool tests has greatly facilitated differentiation from celiac disease and inflammatory bowel disease, respectively. In the older, female diarrhea sufferer microscopic colitis should be considered. The role of bile acid diarrhea in the individual with diarrhea-predominant IBS is emphasized; the status of small intestinal bacterial overgrowth in IBS remain uncertain.

SUMMARY

Attention to detail in the clinical evaluation of the individual with IBS-like symptoms will facilitate a selective and targeted approach to investigation. Wherever indicated, widely available serological and fecal tests will serve to bolster the diagnosis by excluding other options. Proceeding to more invasive testing should be dictated by clinical presentation and scenario with the threshold for intervention being generally lower among those with prominent diarrhea.

ACG Clinical Guideline: Management of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a highly prevalent, chronic disorder that significantly reduces patients' quality of life. Advances in diagnostic testing and in therapeutic options for patients with IBS led to the development of this first-ever American College of Gastroenterology clinical guideline for the management of IBS using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Twenty-five clinically important questions were assessed after a comprehensive literature search; 9 questions focused on diagnostic testing; 16 questions focused on therapeutic options. Consensus was obtained using a modified Delphi approach, and based on GRADE methodology, we endorse the following: We suggest that a positive diagnostic strategy as compared to a diagnostic strategy of exclusion be used to improve time to initiating appropriate therapy. We suggest that serologic testing be performed to rule out celiac disease in patients with IBS and diarrhea symptoms. We suggest that fecal calprotectin be checked in patients with suspected IBS and diarrhea symptoms to rule out inflammatory bowel disease. We recommend a limited trial of a low fermentable oligosaccharides, disacchardies, monosaccharides, polyols (FODMAP) diet in patients with IBS to improve global symptoms. We recommend the use of chloride channel activators and guanylate cyclase activators to treat global IBS with constipation symptoms. We recommend the use of rifaximin to treat global IBS with diarrhea symptoms. We suggest that gut-directed psychotherapy be used to treat global IBS symptoms. Additional statements and information regarding diagnostic strategies, specific drugs, doses, and duration of therapy can be found in the guideline.

Epidemiology, Presentation, and Diagnosis of Celiac Disease

The incidence of celiac disease is increasing, partly because of improved recognition of, and testing for, the disease. The rise in incidence is also due to a real increase of this immune-based disorder, independent of disease detection. The reasons for this true rise in recent decades are unknown but may be related to environmental factors that may promote loss of tolerance to dietary gluten. Strategies to reduce the development of celiac disease have not been proven successful in randomized trials, but the quantity of early-life gluten exposure has been a major focus of prevention efforts. The criteria for the diagnosis of celiac disease are changing, but in adults, diagnosis still depends on the presence of duodenal villous atrophy while the patient is on a gluten-containing diet, along with findings from serology analysis. Although guidelines in the United States continue to mandate a biopsy at all ages, some children receive a diagnosis of celiac disease without a biopsy. If proven accurate and scalable, assays that detect gluten-HLA tetramer complexes might be used in diagnosis to be made in the context of a gluten-free diet without intestinal biopsy.