Ulcerative colitis and irritable bowel patients exhibit distinct abnormalities of the gut microbiota

Background  

Previous studies suggest a link between gut microbiota and the development of ulcerative colitis (UC) and irritable bowel syndrome (IBS). Our aim was to investigate any quantitative differences in faecal bacterial compositions in UC and IBS patients compared to healthy controls, and to identify individual bacterial species that contribute to these differences.     

Microbial community analysis reveals high level phylogenetic alterations in the overall gastrointestinal microbiota of diarrhoea-predominant irritable bowel syndrome sufferers

Background  

A growing amount of scientific evidence suggests that microbes are involved in the aetiology of irritable bowel syndrome (IBS), and the gastrointestinal (GI) microbiota of individuals suffering from diarrhoea-predominant IBS (IBS-D) is distinguishable from other IBS-subtypes. In our study, the GI microbiota of IBS-D patients was evaluated and compared with healthy controls (HC) by using a high-resolution sequencing method. The method allowed microbial community analysis on all levels of microbial genomic guanine plus cytosine (G+C) content, including high G+C bacteria.     

Effect of a multispecies probiotic supplement on quantity of irritable bowel syndrome-related intestinal microbial phylotypes

Background  

Probiotics can alleviate the symptoms of irritable bowel syndrome (IBS), possibly by stabilizing the intestinal microbiota. Our aim was to determine whether IBS-associated bacterial alterations were reduced during multispecies probiotic intervention consisting of Lactobacillus rhamnosus GG, L. rhamnosus Lc705, Propionibacterium freudenreichii ssp. shermanii JS and Bifidobacterium breve Bb99. The intervention has previously been shown to successfully alleviate gastrointestinal symptoms of IBS.     

Luminal and mucosal-associated intestinal microbiota in patients with diarrhea-predominant irritable bowel syndrome

Background

Recent studies have suggested a role for an altered intestinal microbiota in the pathophysiology of irritable bowel syndrome (IBS). However, no consensus has been reached regarding the association between specific enteric bacterial groups and IBS. The aim of this study was to investigate the fecal and mucosal-associated microbiota using two independent techniques in intestinal samples from diarrhea-predominant IBS (D-IBS) and healthy controls.

Methods

Fecal and colonic mucosal biopsy samples were obtained from 10 D-IBS patients and 10 healthy controls. Colonic tissue was collected during a un-sedated un-prepped flexible sigmoidoscopy. Fecal and tissue samples were processed immediately upon collection for culture under aerobic and anaerobic conditions or frozen for further molecular analysis. DNA was extracted from all frozen samples and used to enumerate specific bacterial groups using quantitative real-time PCR (qPCR).

Results

Culture analysis of intestinal samples demonstrated a significant reduction in the concentration of aerobic bacteria in fecal samples from D-IBS patients when compared to healthy controls (1.4 × 10⁷ vs. 8.4 × 10⁸ CFUs/g feces, P = 0.002). qPCR analysis demonstrated a significant 3.6 fold increase (P = 0.02) in concentrations of fecal Lactobacillus species between D-IBS patients and healthy controls.

Conclusions

Our culture and molecular data indicate that quantitative differences exist in specific bacterial groups in the microbiota between D-IBS and healthy subjects.     

The Expression of Protease-Activated Receptor 2 and 4 in the Colon of Irritable Bowel Syndrome Patients

Background  

Irritable bowel syndrome (IBS) pathophysiology has not been fully understood. Abnormalities of serine proteases have been identified in IBS patients. In addition, protease-activated receptors (PAR) activation interferes with several components of the pathogenesis of IBS, so, evaluating the PAR expression in IBS patients may contribute to understanding the pathogenesis of the disease.     

Proton Pump Inhibitor Therapy Does Not Affect Hydrogen Production on Lactulose Breath Test in Subjects with IBS

Background  

Evidence suggests a role for small intestinal bacterial overgrowth (SIBO) in IBS. Recently, the question has arisen whether the lactulose breath test (LBT) is abnormal in IBS subjects due to overlapping GERD and proton-pump inhibitor (PPI) usage.     

A systematic review and meta-analysis: probiotics in the treatment of irritable bowel syndrome

Background  

Irritable Bowel Syndrome (IBS) is a common chronic gastrointestinal disorder and the evidence for efficacy of most drug therapies in the treatment of IBS is weak. A popular alternative is probiotics, which have been used in several conditions. including IBS. Probiotics are live microbial food supplements.     

How does comorbidity affect cost of health care in patients with irritable bowel syndrome? A cohort study in general practice

Background  

Irritable bowel syndrome (IBS) is associated with other disorders (comorbidity), reduced quality of life and increased use of health resources. We aimed to explore the impact of comorbidity on cost of health care in patients with IBS in general practice.     

Serotonin Transporter and G Protein Beta 3 Subunit Gene Polymorphisms in Greeks with Irritable Bowel Syndrome

Background  

Polymorphisms in the serotonin transporter (SERT) and G protein β3 subunit (GNB3) genes might contribute to the pathophysiology of irritable bowel syndrome (IBS). Association studies of SERT and GNB3 polymorphisms and IBS have shown diverse results among different populations, which might be due to subject composition differences.     

Dietary intakes in people with irritable bowel syndrome

Background  

Irritable Bowel Syndrome (IBS) is a functional bowel disorder characterised by episodes of abdominal pain associated with altered bowel habits. Many IBS sufferers believe that diet may play a role in triggering these episodes and may avoid certain foods. However relatively few studies have undertaken a dietary assessment in IBS sufferers to examine the wider impact of the condition upon diet.     

Evaluation of the Birmingham IBS symptom questionnaire

Background  

Irritable Bowel Syndrome (IBS) is a chronic/common condition that causes a significant effect on the individual (reduced quality of life), society (time lost off work) and health services. Comparison of studies evaluating the management of IBS has been hindered by the lack of a widely adopted validated symptom score. The aim of this study was to develop and validate a disease specific score to measure the symptoms of patients with IBS.     

Prospective Diary Evaluation of Unexplained Abdominal Pain and Bowel Dysfunction: A Population-Based Colonoscopy Study

Introduction  

Diagnostic criteria for irritable bowel syndrome (IBS) have not been validated by prospective symptom diary. We investigated the bowel patterns in community subjects with and without non-organic abdominal pain, and compared the symptoms with subjects fulfilling the Rome II criteria (IBS).     

Is the Colonic Response to Food Different in IBS in Contrast to Simple Constipation or Diarrhea Without Abdominal Pain?

Background  

Colonic response to food (CRF) is abnormal in irritable bowel syndrome (IBS) patients.     

Gut dysbiosis and irritable bowel syndrome: The potential role of probiotics

Objective

To discuss the role of gut dysbiosis in the development of irritable bowel syndrome (IBS) and the impact of probiotics as a potential therapeutic measure.

Neural Autoantibody Evaluation in Functional Gastrointestinal Disorders: A Population-Based Case–Control Study

Background  

Our goal is to investigate the serum profile of neural autoantibodies in community-based patients with irritable bowel syndrome (IBS) or functional dyspepsia. The pathogenesis of functional gastrointestinal (GI) disorders, including IBS and dyspepsia, are unknown. Theories range from purely psychological to autoimmune alterations in GI tract neuromuscular function.     

Real-time PCR analysis of enteric pathogens from fecal samples of irritable bowel syndrome subjects

Background

Growing amount of scientific evidence suggests that microbes are involved in the pathophysiology of irritable bowel syndrome (IBS). The predominant fecal microbiota composition of IBS subjects has been widely studied with DNA-based techniques but less research has been focused on the intestinal pathogens in this disorder. Here, we optimized a highly sensitive panel of 12 quantitative real-time PCR (qPCR) assays to shed light on the putative presence of intestinal pathogens in IBS sufferers. The panel was used to screen fecal samples from 96 IBS subjects and 23 healthy controls.

Results

Fifteen IBS samples (17%) tested positive for Staphylococcus aureus with a thermonuclease (nuc) gene-targeting qPCR assay, whereas none of the healthy controls were positive for S. aureus (p < 0.05). The S. aureus -positive IBS samples were confirmed by sequencing of the PCR amplicons. Clostridium perfringens was detected from IBS and control groups with a similar frequency (13% and 17%, respectively) with α-toxin (plc) gene -targeting qPCR assay while none of the samples tested positive for the Cl. perfringens enterotoxin-encoding gene (cpe).

Conclusions

The qPCR panel consisting of 12 assays for an extensive set of pathogenic microorganisms provides an efficient alternative to the conventional detection of gastrointestinal pathogens and could accelerate the initiation of targeted antibiotic therapy reducing the risk of post-infectious IBS (PI-IBS). S. aureus has not been previously reported to be associated with the onset of IBS. Although we discovered significant differences in the prevalence of S. aureus between the study groups, its importance in giving rise to IBS symptoms requires further studies.     

Elevated expression of c-fos in central nervous system correlates with visceral hypersensitivity in irritable bowel syndrome (IBS): a new target for IBS treatment

Background and aims  

Although visceral hypersensitivity is a major pathophysiological feature of irritable bowel syndrome (IBS), its molecular mechanisms are still poorly understood. c-fos is a well-established marker of cell activation. Accumulating evidence demonstrates that norepinephrine (NE) system is dysregulated in IBS; however, very little is known on its mechanism. It is our hypothesis that elevated expression of c-fos in central nervous system (CNS) correlates with visceral hypersensitivity in rat model of IBS. Furthermore, we explored the changes of NE system in IBS patients.     

<Emphasis Type="Italic">Chlamydia trachomatis</Emphasis> antigens in enteroendocrine cells and macrophages of the small bowel in patients with severe irritable bowel syndrome

Background  

Inflammation and immune activation have repeatedly been suggested as pathogentic factors in irritable bowel syndrome (IBS). The driving force for immune activation in IBS remains unknown. The aim of our study was to find out if the obligate intracellular pathogen Chlamydia could be involved in the pathogenesis of IBS.     

Microbiota,infecciones gastrointestinales,inflamación de bajo grado y antibioticoterapia en el síndrome de intestino irritable. Una revisión basada en evidencias

BackgroundPost-infectious irritable bowel syndrome (PI-IBS) prevalence, small intestinal bacterial overgrowth (SIBO), altered microbiota, low-grade inflammation, and antibiotic therapy in IBS are all controversial issues.AimsTo conduct an evidence-based review of these factors.MethodsA review of the literature was carried out up to July 2012, with the inclusion of additional articles as far as August 2013, all of which were analyzed through the Oxford Centre for Evidence-Based Medicine (OCEBM) system.Results1. There is greater SIBO probability in IBS when breath tests are performed, but prevalence varies widely (2-84%). 2. The gut microbiota in individuals with IBS is different from that in healthy subjects, but a common characteristic present in all the patients has not been established. 3. The incidence and prevalence of PI-IBS varies from 9-10% and 3-17%, respectively, and the latter decreases over time. Bacterial etiology is the most frequent but post-viral and parasitic cases have been reported. 4. A sub-group of patients has increased enterochromaffin cells, intraepithelial lymphocytes, and mast cells in the intestinal mucosa, but no differences between PI-IBS and non-PI-IBS have been determined. 5. Methanogenic microbiota has been associated with IBS with constipation. 6. Rifaximin at doses of 400 mg TID/10 days or 550 mg TID/14 days is effective treatment for the majority of overall symptoms and abdominal bloating in IBS. Retreatment effectiveness appears to be similar to that of the first cycle.ConclusionsFurther studies are required to determine the nature of the gut microbiota in IBS and the differences in low-grade inflammation between PI-IBS and non-PI-IBS. Rifaximin has shown itself to be effective treatment for IBS, regardless of prior factors.     

Development and psychometric testing of the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS)

Background  

The aim of this study was to develop and psychometrically test a short, patient-reported questionnaire to be used in clinical practice for patients with Irritable Bowel Syndrome (IBS). The Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS) questionnaire was designed to measure the treatment response of symptoms and well-being in patients suffering from IBS.