Abstract. Diet is important in triggering the symptoms of irritable bowel syndrome (IBS). This study investigated the impact of dietary guidance on the symptoms, quality of life and habitual diet of patients with IBS. Forty-six patients who included. Of these patients, 17 completed the entire study. Each patient attended three sessions (~45 min in duration) and received individual guidance on their dietary management. The patients were asked to complete the following questionnaires prior to receiving the dietary guidance, and at least 3 months subsequently: The Birmingham IBS symptom score questionnaire, the IBS Quality of Life (IBS-QOL) questionnaire, the Short-Form Nepean and Dyspepsia Index (SF-NDI) and the MoBa Food Frequency Questionnaire (MoBa FFQ). The time at which patients completed the questionnaires following dietary guidance ranged from 3-9 months (median, 4 months). The total IBS symptom scores were reduced once the patients had received dietary guidance (P=0.001). The total score for the quality of life, as assessed by the IBS-QOL guidance sessions (P=0.003 and P=0.002, respectively). There were no statistical differences in the intake of calories, IBS following dietary guidance. There were increases in the consumption of dairy products, -carotene, retinol equivalents, 12 and calcium, although only the increase in vitamin B 12 and vegetables that were rich in highly fermentable short-chain carbohydrates, disaccharides, monosaccharides and polyols, as guidance sessions, administered by a nurse, reduced the symptoms and improved the quality of life of patients with IBS, and resulted in an adequate intake of vitamins and minerals. Individual dietary guidance is a cost-effective option for the management of IBS. IntroductionIrritable bowel syndrome (IBS) is a chronic functional bowel disorder characterized by a combination of symptoms that have a considerable impact on the patient's quality of life. These symptoms include abdominal pain or discomfort and altered bowel habits (1,2). IBS is more common in females than in males, and is diagnosed more frequently in patients under the age of 50 (1). The prevalence of IBS has been calculated to range from 5-15% of the population worldwide, as determined by diagnostic criteria, such as the Rome criteria (1-14).Approximately two-thirds of patients with IBS consider their symptoms to be related to their diet (15) and therefore restrict their intake of certain dietary agents that they perceive to be provocative. The most commonly reported triggers are carbohydrates and fatty foods, milk and dairy products, wheat products, caffeine, hot spices, certain meats, cabbage, onions, peas, beans and fried and smoked foods (16)(17)(18)(19). Despite these reported effects, numerous studies have demonstrated that dietary composition does not markedly differ between patients with IBS and controls (15-21), although patients with IBS appear to have a low intake of calcium, potassium, magnesium, vitamin A, vitamin B 12 In a previous study by our group, dietary guidance admini...

Irritable bowel syndrome (IBS) is a common chronic gastrointestinal disorder. It is widely believed that IBS is caused by a deficient intake of dietary fiber, and most physicians recommend that patients with IBS increase their intake of dietary fiber in order to relieve their symptoms. However, different types of dietary fiber exhibit marked differences in physical and chemical properties, and the associated health benefits are specific for each fiber type. Short-chain soluble and highly fermentable dietary fiber, such as oligosaccharides results in rapid gas production that can cause abdominal pain/discomfort, abdominal bloating/distension and flatulence in patients with IBS. By contrast, long-chain, intermediate viscous, soluble and moderately fermentable dietary fiber, such as psyllium results in a low gas production and the absence of the symptoms related to excessive gas production. The effects of type of fiber have been documented in the management of IBS, and it is known to improve the overall symptoms in patients with IBS. Dietary fiber acts on the gastrointestinal tract through several mechanisms, including increased fecal mass with mechanical stimulation/irritation of the colonic mucosa with increasing secretion and peristalsis, and the actions of fermentation byproducts, particularly short-chain fatty acids, on the intestinal microbiota, immune system and the neuroendocrine system of the gastrointestinal tract. Fiber supplementation, particularly psyllium, is both safe and effective in improving IBS symptoms globally. Dietary fiber also has other health benefits, such as lowering blood cholesterol levels, improving glycemic control and body weight management.

BackgroundGut microbiota alterations are important in irritable bowel syndrome (IBS). The aim was to investigate the effect of fecal microbiota transplantation (FMT) on gut microbiota and the symptoms in patients with IBS.Material and methodsThe study included 13 IBS patients according to Rome III criteria and 13 healthy donors. Freshly donated feces were administered to the descending part of the duodenum via a gastroscope. Feces were collected from donors and patients before FMT, and from the patients at 1, 3 and 12 weeks and donors and patients at 20/28 weeks after FMT. Microbiota analysis was performed using GA-map Dysbiosis test (Genetic Analysis AS, Oslo, Norway). The patients completed the following questionnaires before and at the aforementioned weeks after FMT: IBS Symptom Questionnaire (IBS-SQ), IBS-Symptom Severity Scoring system (IBS-SSS), Short Form of Nepean Dyspepsia Index (SF-NDI), Bristol stool form scale, the Eysenck Personality Questionnaire-Neuroticism and Hospital Anxiety and Depression.ResultsDonors and IBS patients had significantly different bacterial strain signals before FMT (Ruminococcus gnavus, Actinobacteria and Bifidobacteria) that became non-significant after 3 weeks following FMT. The changes in gut microbiota were similar between donors and patients at 20/28 weeks after FMT. Thus, patients’ microbiota profiles became more-or-less similar to donors.The scores of all the questionnaires were significantly improved at all time points following FMT. No reported adverse effects.ConclusionsFMT was associated with a change in gut microbiota and improvement in IBS symptoms and quality of life lasting for up to 28 weeks.Trial registrationClinicalTrials.gov ID: NCT03333291

Irritable bowel syndrome (IBS) is a widespread gastrointestinal disorder affecting 11.2% of the world adult population. The intestinal microbiome is thought to play a pivotal role in the pathophysiology of IBS. The composition of the fecal microbiome in IBS patients differs from that in healthy individuals, but the exact bacteria species involved in the development of IBS remain to be determined. There is also an imbalance between useful and harmful bacteria (dysbiosis) in the intestinal microbiome in patients with IBS. Consuming prebiotics, probiotics, or synbiotics has a limited effect on IBS symptoms. In contrast, fecal microbiome transplantation (FMT) in IBS patients reverses the dysbiosis to normobiosis and reduces the IBS symptoms in about 70% of patients, and is not associated with any serious adverse events. Area covered: The available data on the microbiome and FMT in IBS regarding the efficacy of FMT in managing IBS were found using a PubMed search of these topics. Expert commentary: FMT is a promising tool for managing irritable syndrome. It appears to be effective, easy, and inexpensive procedure. However, more controlled studies involving larger cohorts of IBS are needed before FMT can be used as a routine procedure in the clinic.

Background/Objectives:To determine the large intestinal endocrine cell types affected following dietary guidance in patients with irritable bowel syndrome (IBS).Subjects/Methods:The study included 13 IBS patients and 13 control subjects. The patients received three sessions of individualized dietary guidance. Both the control subjects and the patients were scheduled for colonoscopies at baseline and again for the patients at 3–9 months after dietary guidance. Biopsy samples were taken from the colon and rectum and were immunostained for all types of large intestinal endocrine cells. The endocrine cells were quantified using computerized image analysis.Results:The daily total consumption (mean±s.e.m. values) of fruits and vegetables rich in FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) decreased significantly from 16.2±5.3 g before receiving dietary guidance to 9.2±3.2 g after receiving dietary guidance (P=0.02). In the total colon, the densities of serotonin cells were 46.8±8.9, 10.5±2.1 and 22.6±3.2 cells/mm2 in control subjects and in IBS patients before and after receiving dietary guidance, respectively (P=0.007); the corresponding densities of peptide YY cells were 11.6±1.8, 10.8±1.7 and 16.8±2.1 cells/mm2, respectively (P=0.06). The cell densities for both serotonin and peptide YY did not change significantly in the rectum. The densities of somatostatin cells in the rectum were 13.5±3.0, 13.2±3.0, and 22.3±3.2 cells/mm2 for control subjects and for IBS patients before and after receiving dietary guidance, respectively (P=0.01).Conclusions:The densities of the large intestinal endocrine cells tend to normalize following dietary guidance that may have contributed to the improvement of the patients with IBS symptoms.

Irritable bowel syndrome (IBS) may be associated with disturbances in gut microbiota composition and functions. We recently performed a study of fecal microbiota transplantation (FMT) in diarrhea-predominant IBS (IBS-D) and found that IBS symptoms improved and the gut microbiota profile changed following FMT.We now aimed to explore the effects of FMT on the gut microenvironment in further detail by using 16S rRNA sequencing for more extended microbiota profiling and analyzing bacterial fermentation products (SCFAs: short chain fatty acids). Materials and methodsThe study included 13 patients (4 females and males) with IBS-D according to Rome III criteria and 13 healthy donors. Freshly donated feces were administered into duodenum via gastroscopy. The patients completed symptom and quality of life (QoL) questionnaires and delivered feces before and 1, 3, 12 and 20/28 weeks after FMT. Microbiota analysis was performed by sequencing 16S rRNA gene with Illumina Miseq technology. Fecal concentrations of SCFAs were analyzed by vacuum distillation followed by gas chromatography. ResultsSeveral gut microbiota taxa and SCFAs were significantly different in the patients at baseline compared to their donors. These differences normalized by the third week following FMT in parallel with significant improvement in symptoms and QoL.Responders had different gut microbiota profile and SCFAs than non-responders.Significant correlations were found between the gut microenvironment and IBS symptoms. No adverse effects were reported. ConclusionsFMT restores alterations of the gut microenvironment in IBS-D patients during the first 3 weeks and improves their symptoms for up to 28 weeks.

Peptide YY (PYY) is affected in several gastrointestinal diseases and disorders. Changes in PYY appear to be an adaptive response to alterations in pathophysiological conditions caused by the disease. This applies to gastrointestinal diseases/disorders such as irritable bowel syndrome, inflammatory bowel disease, celiac disease, systemic sclerosis, and post-intestinal resection. By contrast, the changes in PYY in chronic idiopathic slow transit constipation (CST) seem to be of a primary nature, and may be one etiological factor of the disease. Abnormalities in PYY seem to contribute to the development of symptoms present in irritable bowel syndrome, inflammatory bowel disease, gastroenteropathy in long-standing diabetes and CST. The changes in PYY could, however, be favorable in some gastrointestinal disorders such as celiac disease, systemic sclerosis and post-intestinal resection state. Investigating changes in PYY in gastrointestinal diseases/disorders could be beneficial in clinical practice, where a receptor agonist or an antagonist can be used as a drug, depending on the condition. Similar to other neuroendocrine peptides/amines of the gut, PYY has broad physiological/pharmacological effects: it can bind to and activate several receptors with independent actions. Thus, in order to use PYY as a drug, receptor-specific agonists or antagonists need to be developed.

The large intestine contains five types of endocrine cells that regulate its functions by sensing its luminal contents and releasing specific hormones. Chromogranin A (CgA) is a common marker for the gastrointestinal endocrine cells, and it is abnormal in irritable bowel syndrome (IBS) patients. Most IBS patients relate their symptoms to certain food elements. The present study investigated the effect of dietary guidance on the total endocrine cells of the large intestine as detected by CgA in 13 IBS patients. Thirteen control subjects were also included. Each patient received three sessions of dietary guidance. Colonoscopies were performed on controls and patients (at baseline and at 3–9 months after receiving guidance). Biopsy samples from the colon and rectum were immunostained for CgA and quantified by computerized image analysis. The densities of CgA cells in the total colon (mean ± SEM) among the controls and the IBS patients before and after receiving dietary guidance were 83.3 ± 10.1, 38.6 ± 3.7, and 64.7 ± 4.2 cells/mm2, respectively (P = 0.0004), and were unchanged in the rectum. In conclusion, the increase in CgA cell density after receiving dietary guidance may reflect a change in the densities of the large intestinal endocrine cells causing an improvement in the IBS symptoms.