Functional Variation in Human CAZyme Genes in Relation to the Efficacy of a Carbohydrate-Restricted Diet in IBS Patients.

Background & Aims: Limiting the dietary intake of certain carbohydrates has therapeutic effects in some but not all irritable bowel syndrome (IBS) patients. We investigated genetic variation in human Carbohydrate-Active enZYmes (hCAZymes) genes in relationship to the response to a FODMAP-lowering diet in the DOMINO study.

Methods: hCAZy polymorphism was studied in patients with IBS from the dietary (FODMAP-lowering; n = 196) and medication (otilonium bromide; n = 54) arms of the DOMINO trial via targeted sequencing of 6 genes of interest (AMY2B, LCT, MGAM, MGAM2, SI, and TREH).

DOMINO trial analysis: evaluation of the diet effects on symptoms in IBS subtypes.

Background: Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction characterized by recurrent abdominal pain related to defecation and/or associated to a change in bowel habits. According to the stool type, four different IBS subtypes can be recognized, constipation predominant (IBS-C), diarrhea predominant (IBS-D), mixed (IBS-M), and undefined (IBS-U). Patients report that their IBS symptoms are exacerbated by food.

Efficacy and Findings of a Blinded Randomized Reintroduction Phase for the Low FODMAP Diet in Irritable Bowel Syndrome.

Background & Aims: The efficacy of a low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet in irritable bowel syndrome (IBS) is well established. After the elimination period, a reintroduction phase aims to identify triggers. We studied the impact of a blinded reintroduction using FODMAP powders to objectively identify triggers and evaluated the effect on symptoms, quality of life, and psychosocial comorbidities.

Effects of corticotropin-releasing hormone on gastric electrical activity and sensorimotor function in healthy volunteers: a double-blinded crossover study.

Biopsychosocial factors are associated with disorders of gut-brain interaction (DGBI) and exacerbate gastrointestinal symptoms. The mechanisms underlying pathophysiological alterations of stress remain unclear. Corticotropin-releasing hormone (CRH) is a central regulator of the hormonal stress response and has diverse impact on different organ systems.

Nutrition and Disorders of Gut-Brain Interaction.

Background: Disorders of gut-brain interaction (DGBIs) have a complex pathophysiology that is often characterized by a relationship between food ingestion and triggering of symptoms. Understanding of the underlying mechanisms and the role of nutrients as a therapeutic target are rapidly evolving.

Aims And Methods: We performed a narrative review of the literature using the following keywords, their acronyms, and their associations: nutrients, disorders of gut-brain interaction; functional dyspepsia; malabsorption; irritable bowel syndrome; diarrhea; constipation.

Mechanisms underlying food-related symptoms in disorders of gut-brain interaction: Course ahead in research and clinical practice.

A subgroup of patients with a disorder of gut-brain interaction (DGBI) report symptoms such as abdominal pain, gas-related symptoms, dyspeptic symptoms and loose stool or urgency after meal intake. Therefore, the effect of several dietary therapies including fibre-rich or restrictive diets have already been studied in patients with irritable bowel syndrome, functional abdominal bloating or distention, and functional dyspepsia. However, there is a paucity of studies in the literature on the mechanisms underlying food-related symptoms.

Prevalence of delayed gastric emptying in patients with gastroparesis-like symptoms.

Background: The European consensus defined gastroparesis as a condition characterised by delayed gastric emptying (GE) in the absence of mechanical obstruction, with a symptom pattern of predominant nausea and/or vomiting and overlapping postprandial distress syndrome (PDS). The distinction between patients with gastroparesis and those with functional dyspepsia (FD), another gastrointestinal condition characterised by predominant PDS or epigastric pain syndrome symptoms, is ongoing.

Aim: To investigate the extent that symptom patterns may differentiate gastroparesis from FD.

Worldwide prevalence and burden of gastroparesis-like symptoms as defined by the United European Gastroenterology (UEG) and European Society for Neurogastroenterology and Motility (ESNM) consensus on gastroparesis.

Background/objectives: The global epidemiology of gastroparesis is unknown. The European UEG and European Society for Neurogastroenterology and motility consensus defines Gastroparesis as a condition characterized by delayed gastric emptying in the absence of mechanical obstruction, with a symptom pattern of nausea and/or vomiting and overlapping postprandial distress syndrome (PDS). Real-world evidence of this gastroparesis-like symptom pattern is a crucial step in understanding the epidemiology of gastroparesis.

Mechanisms Underlying Food-Triggered Symptoms in Disorders of Gut-Brain Interactions.

There has been a dramatic increase in clinical studies examining the relationship between disorders of gut-brain interactions and symptoms evoked by food ingestion in the upper and lower gastrointestinal tract, but study design is challenging to verify valid endpoints. Consequently, mechanistic studies demonstrating biological relevance, biomarkers and novel therapeutic targets are greatly needed. This review highlights emerging mechanisms related to nutrient sensing and tasting, maldigestion, physical effects with underlying visceral hypersensitivity, allergy and immune mechanisms, food-microbiota interactions and gut-brain signaling, with a focus on patients with functional dyspepsia and irritable bowel syndrome.

Diet or medication in primary care patients with IBS: the DOMINO study - a randomised trial supported by the Belgian Health Care Knowledge Centre (KCE Trials Programme) and the Rome Foundation Research Institute.

Background: In Europe, IBS is commonly treated with musculotropic spasmolytics (eg, otilonium bromide, OB). In tertiary care, a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet provides significant improvement. Yet, dietary treatment remains to be explored in primary care.

Postinfectious onset in functional dyspepsia is a risk factor for weight loss.

Background: Functional dyspepsia (FD) is differentiated into two subgroups: the postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). Acute gastroenteritis and Helicobacter pylori (HP) infection have been identified as risk factors for FD. It is unclear how these risk factors relate to Rome IV subgroups and their clinical impact.

The gastrointestinal tract in hunger and satiety signalling.

Background: Different peripheral pathways are implicated in the regulation of the food ingestion-digestion cycle.

Methods: Narrative review on gastrointestinal mechanisms involved in satiety and hunger signalling.

Results: Combined mechano- and chemoreceptors, peripherally released peptide hormones and neural pathways provide feedback to the brain to determine sensations of hunger (increase energy intake) or satiation (cessation of energy intake) and regulate the human metabolism.

Nutrient Drinking Test as Biomarker in Functional Dyspepsia.

Introduction: Functional dyspepsia (FD) is a prevalent condition with multifactorial pathophysiology, including impaired gastric accommodation (GA), hypersensitivity to gastric distention, and delayed gastric emptying. Drink tests (DT) have been proposed as a potential biomarker for the presence and severity of gastric sensorimotor dysfunction. Thus, we aimed to summarize the state of knowledge on different DT and their potential as a biomarker for FD.

Relationship Between Gastric Emptying Rate and Simultaneously Assessed Symptoms in Functional Dyspepsia.

Methods: During a GE test (breath test with C-octanoic acid labelled 250 kcal solid meal), the severity of 6 symptoms (postprandial fullness, epigastric pain and burning, bloating, nausea and belching) was assessed, every 15 min, before meal-intake and 4h postprandially. The sum of individual symptom scores generated the meal-related symptoms score; the sum of all symptoms generated overall meal-related symptom severity (OSS). Data were compared in patients with normal and delayed GE (cut-off T≥ 109 min).

Paradigm Shift: Functional Dyspepsia-A "Leaky Gut" Disorder?

For up to 2 decades, pathophysiological research in functional dyspepsia focused on gastric sensorimotor dysfunction underlying symptom generation. Recent pathophysiological research has focused on low-grade inflammation in the duodenal mucosa. Emerging evidence confirms a loss of mucosal integrity in the duodenum in functional dyspepsia, and this is confirmed in a confocal laser endomicroscopy study demonstrating altered mucosal barrier function and pyroptosis.

Effects of Rome IV Definitions of Functional Dyspepsia Subgroups in Secondary Care.

Background & Aims: Functional dyspepsia (FD) is subdivided into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) according to the Rome III consensus. In clinical practice, there is a major overlap between these subgroups. The Rome IV criteria included postprandially occurring symptoms in the PDS subgroup.

Recent advances in diagnosis and management of irritable bowel syndrome.

Purpose Of Review: This review summarizes recent progress in the diagnosis and management of irritable bowel syndrome, with a focus on dietary and microbiota aspects.

Recent Findings: From a pathophysiological point of view, IBS is a multifactorial condition with both peripheral (transit) as central (visceral hypersensitivity, anxiety, depression) contribution in a cumulative fashion to the symptom pattern and severity. More recently, the focus has shifted to diet and microbiota.

A survey on the impact of the COVID-19 pandemic on motility and functional investigations in Europe and considerations for recommencing activities in the early recovery phase.

Background: The COVID-19 pandemic, declared by WHO on March 13, 2020, had a major global impact on the healthcare system and services. In the acute phase, the presence of the SARS-CoV-2 virus in the aerodigestive tract limited activities in the gastroenterology clinic and procedures to emergencies only. Motility and function testing was interrupted and as we enter the recovery phase, restarting these procedures requires a safety-focused approach with adequate infection prevention for patients and healthcare professionals.

The Role of GI Peptides in Functional Dyspepsia and Gastroparesis: A Systematic Review.

Functional dyspepsia (FD) and gastroparesis (GP) are common disorders of the upper gastrointestinal tract. The pathophysiology of these conditions is likely to be heterogenous, and factors such as altered motility, sensitivity and response to nutrition have been identified as putative underlying mechanisms. Motility, sensitivity as well as responses to nutrition can be influenced or mediated by peptide hormones and serotonin released from the gastrointestinal mucosa.

Mast cell-nerve interactions correlate with bloating and abdominal pain severity in patients with non-celiac gluten / wheat sensitivity.

Background: Gastrointestinal (GI) and extra-GI symptoms/manifestations represent key clinical features of patients with non-celiac gluten/wheat sensitivity (NCG/WS). This study aimed to investigate neuro-immune (focusing on mast cells, MCs) interactions in the duodenal submucosa of patients with NCG/WS.

Methods: Submucosal whole mounts from duodenal biopsies of 34 patients with self-reported NCG/WS, 28 with celiac disease (CD), 13 with functional dyspepsia (FD), and 24 healthy controls (HC) were analyzed by immunohistochemistry.

Prevalence and impact of self-reported painful and non-painful constipation in the general population.

Introduction: Chronic constipation, defined by the Rome IV criteria, is a highly prevalent functional bowel disorder with major overlap with other bowel disorders. Therefore, a pooled-analysis to evaluate the presence of self-reported constipation in the general population was conducted. Further, its association with other bowel symptoms and its health-economic impact was analyzed.