Irritable bowel syndrome

The Potential Role of Human Milk Oligosaccharides in Irritable Bowel Syndrome

Irritable Bowel Syndrome (IBS) is the most common gastrointestinal (GI) disorder in Western populations and therefore a major public health/economic concern. However, despite extensive research, psychological and physiological factors that contribute to the aetiology of IBS remain poorly understood. Consequently, clinical management of IBS is reduced to symptom management through various suboptimal options. Recent evidence has suggested human milk oligosaccharides (HMOs) as a potential therapeutic option for IBS. Here, we review literature concerning the role of HMOs in IBS, including data from intervention and in vitro trials. HMO supplementation shows promising results in altering the gut microbiota and improving IBS symptoms, for instance by stimulating bifidobacteria. Further research in adults is required into HMO mechanisms, to confirm the preliminary results available to date and recommendations of HMO use in IBS.

Ameliorative Effects of Humulus japonicus Extract and Polysaccharide-Rich Extract of Phragmites rhizoma in Rats with Gastrointestinal Dysfunctions Induced by Water Avoidance Stress

Chronic stress can cause the gastrointestinal disorders characterized by an altered bowel movement and abdominal pain. Studies have shown that Humulus japonicus extract (HJE) has anti-inflammatory and antidiarrheal effects, and Phragmites rhizoma extract (PEP) has antioxidative and antistress effects. The present study aimed to investigate the possible effects of HJE and PEP in rat models with stress-induced gastrointestinal dysfunctions. The rats were exposed to water avoidance stress (WAS, 1 h/day) for 10 days to induce gastrointestinal disorders. We found that WAS significantly increased fecal pellet output during 1 h stress, gastric emptying, colonic contractility, and permeability compared to the normal rats. Pretreatment with HJE and PEP (0.25 and 0.5 mL/kg, both administered separately) improved the increased gastric emptying and colonic contractility induced by electrical field stimulation, acetylcholine, and serotonin and also alleviated the increased colonic permeability. HJE and PEP also increased the claudin-1 and occludin expressions, reduced by WAS. WAS increased the concentration of TNF-α and TBARS and reduced FRAP. HJE and PEP recovered these effects. HJE and PEP improved the gastrointestinal disorders induced by WAS by upregulating the tight junction protein, possibly acting on cholinergic and serotonergic receptors to abolish the colonic hypercontractility and hyperpermeability and degradation of inflammatory cytokines via an antioxidant effect.

Gluten Free Diet for the Management of Non Celiac Diseases: The Two Sides of the Coin

A lifelong adherence to a gluten-free (GF) diet is currently the only treatment for Celiac disease (CD), an autoimmune disorder that arises after gluten ingestion in individuals who are genetically predisposed. The gluten intake exerts toxic effects through several pathways involving gut barrier integrity, intestinal microbiota composition and immune system stimulation. However, despite the great benefit of GF diet for CD patients, its use has been debated. Indeed, individuals who adopt this diet regime may be at risk of nutrient deficiencies. Emerging evidence supports a beneficial effect of a GF diet also for other pathological conditions, including gluten-related disorders (GRD) often associated to CD, such as Non celiac gluten sensitivity (NCGS) and Dermatitis Herpetiforme (DH) as well as Irritable bowel syndrome (IBS) and Diabetes. This suggests a pathogenic role of gluten in these conditions. Despite the growing popularity of GF diet among consumers, to date, there are limited evidences supporting its use for the management of non-celiac diseases. Therefore, in this review, we discuss whether the GF diet could really improve the general quality of life of patients with GRD and non-GRD conditions, keeping in mind its sensorial limitations and nutritional inadequacies. In addition, we discuss the current motivations, leading to the use of a GF diet, despite the inferior quality of GF products respect to those containing gluten.

Epidemiology of irritable bowel syndrome and its associated factors in Saudi undergraduate students

BACKGROUND/AIM

Irritable bowel syndrome (IBS) is common among undergraduate students and is associated with several modifiable risk factors. The present study aimed to explore the epidemiology of IBS in Saudi undergraduate students.

MATERIALS AND METHODS

A cross-sectional study was carried out from February 2018 to June 2018. A total of 767 undergraduate students from all regions of Saudi Arabia completed an online self-administered questionnaire. IBS symptoms were assessed using the Rome IV diagnostic criteria.

RESULTS

The mean age was 21.88 years (range 18-29); 56.1% of the study population were females and 50.1% were from the central region of Saudi Arabia. Students of medical colleges represented 30.2% of the sample. The overall prevalence of IBS was 15.8%. Significant independent risk factors for IBS were female sex (OR = 3.738; 95% CI = 2.093, 6.673), being a student in a medical college (OR = 7.216; 95% CI = 4.438, 11.733), living in a rented apartment (OR = 6.752; 95% CI = 2.586, 17.627), living on campus (OR = 6.563; 95% CI = 2.138, 20.145), poor sleep quality (OR = 3.156; 95% CI = 1.850, 5.385), exercise (OR = 0.394; 95% CI = 0.193, 0.803), smoking (OR = 5.256; 95% CI = 2.841, 9.724), family history of IBS (OR = 1.641; 95% CI = 1.012, 2.661), and emotional stress (OR = 2.184; 95% CI = 1.375, 3.469).

CONCLUSION

Overall, 15.8% of participants in this study met the Rome IV criteria for IBS diagnosis. IBS was associated with several lifestyle factors, as well as family history and emotional stress.

Comparative Effect of the I3.1 Probiotic Formula in Two Animal Models of Colitis

Use of probiotic therapy is an active area of investigation to treat intestinal disorders. The clinical benefits of the I3.1 probiotic formula (Lactobacillus plantarum (CECT7484, CECT7485) and P. acidilactici (CECT7483)) were demonstrated in irritable bowel syndrome (IBS) patients in a randomized, double-blind, placebo-controlled clinical trial. The aim of this study was to evaluate the therapeutic effects of I3.1 in two experimental models of colitis, a dextran sulfate sodium (DSS)-induced colitis model and an interleukin (IL)-10-deficient mice model. Colitis was induced in 32 8-week-old Balb/c mice by administering 3% (w/v) DSS in drinking water for 5 days. Probiotics were administered orally (I3.1 or VSL#3, 1 × 10⁹ CFU daily) for 10 days before the administration of DSS. Also, probiotics (I3.1 or VSL#3, 1 × 10⁹ CFU daily) were administered orally to 36 6-week-old C57B6J IL-10(-/-) mice for 10 weeks. Body weight was recorded daily. Colon samples were harvested for histological examination and cytokine measurements. Body weight after DSS administration did not change in the I3.1 group, whereas the VSL#3 group had weight loss. Also, I3.1 normalized IL-6 to levels similar to that of healthy controls and significantly increased the reparative histologic score. In the IL-10-deficient model, both VSL#3 and I3.1 reduced the severity of colitis compared to untreated controls, and I3.1 significantly reduced the levels of IFN-γ compared to the other two groups. In conclusion, I3.1 displays a protective effect on two murine models of experimental colitis. Results suggest that the mechanism of action could be different from VSL#3.

Factors associated with poor therapeutic response in outpatients with irritable bowel syndrome: a multicenter study in Japan

BACKGROUND

Some patients with irritable bowel syndrome (IBS) show poor response to treatment. However, risk factors associated with poor therapeutic response have not been determined.

METHODS

This multicenter trial evaluated consecutive outpatients with IBS undergoing treatment for more than 1 month. Mental health status and physical function were evaluated using the Japanese version of the SF-8. Therapeutic response was evaluated using the IBS severity index-Japanese version (IBS-SIJ). Patients with IBS-SIJ scores ≥175 were defined as poor responders to treatment, whereas those with IBS-SIJ scores <175 were defined as good responders. The demographic and clinical characteristics of these two groups, along with medications, were compared.

RESULTS

The study enrolled 131 participants, 75 with IBS-SIJ scores ≥175-56 with IBS-SIJ scores <175. Multiple logistic regression analysis showed that female sex [odds ratio (OR) 2.67, 95 % confidence interval (CI) 1.19-5.97, p = 0.0167] and mental component summary (MCS) of the SF-8 <40 (OR 2.58, 95 % CI 1.12-5.97, p = 0.0263) were independent risk factors for poor therapeutic response in patients with IBS.

CONCLUSIONS

Lower MCS and female sex were risk factors for poor therapeutic response in patients with IBS. Ascertaining the mechanisms by which lower MCS and female sex are associated with poor therapeutic response in IBS may help design better treatments (Trial registration number: UMIN000016804).

Irritable bowel syndrome: an integrated explanatory model for clinical practice

BACKGROUND

Although irritable bowel syndrome (IBS) is a symptom-based diagnosis, clinicians' management of and communication about the disorder is often hampered by an unclear conceptual understanding of the nature of the problem. We aimed to elucidate an integrated explanatory model (EM) for IBS from the existing literature for pragmatic use in the clinical setting.

METHODS

Systematic and exploratory literature searches were performed in PubMed to identify publications on IBS and EMs.

KEY RESULTS

The searches did not identify a single, integrated EM for IBS. However, three main hypotheses were elucidated that could provide components with which to develop an IBS EM: (i) altered peripheral regulation of gut function (including sensory and secretory mechanisms); (ii) altered brain-gut signaling (including visceral hypersensitivity); and (iii) psychological distress. Genetic polymorphisms and epigenetic changes may, to some degree, underlie the etiology and pathophysiology of IBS and could increase the susceptibility to developing the disorder. The three model components also fit into one integrated explanation for abdominal symptoms and changes in stool habit. Additionally, IBS may share a common pathophysiological mechanism with other associated functional syndromes.

CONCLUSIONS & INFERENCES

It was possible to elucidate an integrated, three-component EM as a basis for clinicians to conceptualize the nature of IBS, with the potential to contribute to better diagnosis and management, and dialog with sufferers.

Faecalibacterium prausnitzii prevents physiological damages in a chronic low-grade inflammation murine model

BACKGROUND

The human gut houses one of the most complex and abundant ecosystems composed of up to 10(13)-10(14) microorganisms. The importance of this intestinal microbiota is highlighted when a disruption of the intestinal ecosystem equilibrium appears (a phenomenon called dysbiosis) leading to an illness status, such as inflammatory bowel diseases (IBD). Indeed, the reduction of the commensal bacterium Faecalibacterium prausnitzii (one of the most prevalent intestinal bacterial species in healthy adults) has been correlated with several diseases, including IBD, and most importantly, it has been shown that this bacterium has anti-inflammatory and protective effects in pre-clinical models of colitis. Some dysbiosis disorders are characterized by functional and physiological alterations. Here, we report the beneficial effects of F. prausnitzii in the physiological changes induced by a chronic low-grade inflammation in a murine model. Chronic low-grade inflammation and gut dysfunction were induced in mice by two episodes of dinitro-benzene sulfonic acid (DNBS) instillations. Markers of inflammation, gut permeability, colonic serotonin and cytokine levels were studied. The effects of F. prausnitzii strain A2-165 and its culture supernatant (SN) were then investigated.

RESULTS

No significant differences were observed in classical inflammation markers confirming that inflammation was subclinical. However, gut permeability, colonic serotonin levels and the colonic levels of the cytokines IL-6, INF-γ, IL-4 and IL-22 were higher in DNBS-treated than in untreated mice. Importantly, mice treated with either F. prausnitzii or its SN exhibited significant decreases in intestinal permeability, tissue cytokines and serotonin levels.

CONCLUSIONS

Our results show that F. prausnitzii and its SN had beneficial effects on intestinal epithelial barrier impairment in a chronic low-grade inflammation model. These observations confirm the potential of this bacterium as a novel probiotic treatment in the management of gut dysfunction and low-grade inflammation.

Non-diarrhoeal increased frequency of bowel movements (IFoBM-ND): enterovirus association with the symptoms in children

OBJECTIVE

Infectious and non-infectious causes are associated with increased frequency of bowel movements (IFoBM). But, a viral aetiology to non-diarrhoeal IFoBM (IFoBM-ND) has not been described. Owing to an accidental infection by an echovirus 19 strain, persistent diarrhoea-associated virus, isolated from a child with persistent diarrhoea, DCR experienced persistent IFoBM-ND with an urgency to pass apparently normal stools more than once each day for about 3 months. A follow-up study was undertaken to determine the prevalence of IFoBM-ND, and association of non-polio enteroviruses (NPEVs) with the symptom in infants from birth to 2 years.

DESIGN

A cohort of 140 newborns was followed for 6 months to 2 years from birth for IFoBM-ND. Stool samples collected every 14 days were examined for NPEVs, rotavirus and other viral/bacterial agents for their possible association with IFoBM-ND and diarrhoea.

RESULTS

Of 403 NPEV infection episodes among 4545 oral polio vaccine strains-negative stool samples, approximately 29% were associated with IFoBM-ND (15% acute and 14% persistent), including resolution of 74% of constipation episodes, and 18% with diarrhoea, suggesting that about 47% of NPEV infection episodes in children below 2 years of age are associated with gastrointestinal symptoms. About 83% of IFoBM-ND episodes are associated with the NPEV infection and 17% of the episodes are of unknown aetiology.

CONCLUSIONS

NPEV is the single most frequently detected viral agent in children with IFoBM-ND and its association with the symptom is highly significant, warranting detailed investigations on the role of NPEVs in gastrointestinal diseases.

Brain and gut interactions in irritable bowel syndrome: new paradigms and new understandings

Irritable bowel syndrome (IBS) is characterized by abdominal pain and altered bowel habits. Visceral hypersensitivity is believed to be a key underlying mechanism that causes pain. There is evidence that interactions within the brain and gut axis (BGA), that involves both the afferent-ascending and the efferent-descending pathways, as well as the somatosensory cortex, insula, amygdala, anterior cingulate cortex, and hippocampus, are deranged in IBS showing both the activation and inactivation. Clinical manifestations of IBS such as pain, altered gut motility, and psychological dysfunction may each be explained, in part, through the changes in the BGA, but there is conflicting information, and its precise role is not fully understood. A better understanding of the BGA may shed more knowledge regarding the pathophysiology of IBS that in turn may lead to the discovery of novel therapies for this common disorder.

On-demand treatment with alverine citrate/simeticone compared with standard treatments for irritable bowel syndrome: results of a randomised pragmatic study

BACKGROUND

In routine practice, irritable bowel syndrome (IBS) symptoms are often difficult to be relieved and impair significantly patients' quality of life (QoL). A randomised, double-blind, placebo-controlled study has shown the efficacy of alverine citrate/simeticone (ACS) combination for IBS symptom relief.

AIM

As IBS symptoms are often intermittent, this pragmatic study was designed to compare the efficacy of an on-demand ACS treatment vs. that of usual treatments.

METHODS

Rome III IBS patients were enrolled by 87 general practitioners who were randomly allocated to one of two therapeutic strategies: on-demand ACS or usual treatment chosen by the physician. The primary outcome measure was the improvement of the IBSQoL score between inclusion and month 6.

RESULTS

A total of 436 patients (mean age: 54.4 years; women: 73.4%) were included, 222 in the ACS arm and 214 patients in the usual treatment arm, which was mainly antispasmodics. At 6 months, improvement of IBSQoL was greater with ACS than with the usual treatment group (13.8 vs. 8.4; p < 0.0008). The IBS-severity symptom score (IBS-SSS) was lower with ACS than in the usual treatment arm with a mean (SE) decrease of 170.0 (6.6) vs. 110.7 (6.7), respectively (p = 0.0001). An IBS-SSS < 75 was more frequent in the ACS group (37.7% vs. 16.0%; p < 0.0001). Improvement of both abdominal pain and bloating severity was also greater with the on-demand ACS treatment, which was associated with both lower direct and indirect costs.

CONCLUSIONS

After 6 months, on-demand ACS treatment led to a greater improvement of QoL, reduced the burden of the disease and was more effective for IBS symptom relief than usual treatments.

Clinical impact of a gluten-free diet on health-related quality of life in seven fibromyalgia syndrome patients with associated celiac disease

BACKGROUND

Celiac disease (CD) is an autoimmune disorder, characterized by the presence of gastrointestinal and multisystem symptoms, which occasionally mimic those of Irritable Bowel Syndrome (IBS) and Fibromyalgia Syndrome (FMS). To assess the effectiveness of a Gluten-Free Diet (GFD) in seven adult female screening-detected CD subjects, categorized as severe IBS and FMS patients.

METHODS

All subjects showed villous atrophy in duodenal biopsies, were HLA-DQ2/DQ8-positive, and fulfilled the Rome III and ACR 1990 criteria respectively for IBS and FMS classification. GFD effectiveness was assessed at baseline and after 1 year, examining the score changes in the Tender Points (TPs) test, Fibromyalgia Impact Questionnaire (FIQ), Health Assessment Questionnaire (HAQ), Short Form Health Survey (SF-36), Visual Analogue Scales (VAS) for gastrointestinal complaints, pain and tiredness, drug prescriptions and tissue-Trans-Glutaminase (tTG) serum levels.

RESULTS

At baseline, all patients had poor Quality of Life and VAS scores, a high number of TPs and drug prescriptions, and increased tTG levels. After 1 year of GFD, all outcome measures significantly improved, with a decrease of 51-60% in TPs, FIQ, HAQ, and VAS scales, and in the number of prescribed drugs, accompanied by an increase of 48-60% in SF-36 Physical and Mental Component Summary scores, and a decrease of tTG to normal values.

CONCLUSION

Results of this pilot study show that the adherence to a GFD by CD-related IBS/FMS patients can simultaneously improve CD and IBS/FMS symptoms, and indicate the merit of further research on a larger cohort.

Treatment of constipation-predominant irritable bowel syndrome by focusing on the liver in terms of Traditional Chinese Medicine: a meta-analysis

OBJECTIVE

To assess the efficacy of Traditional Chinese Medicine (TCM) on constipation-predominant irritable bowel syndrome by focusing on the liver.

METHODS

Databases (domestic and foreign) were searched with the key words "irritable bowel syndrome'", "constipation", and "Chinese medicine"; the relevant articles were retrieved and evaluated. Cure rate, "remarkable efficacy", recurrence rate and the incidence of adverse reactions were the outcome indicators. Review Manager ver 5.1 was used for this meta-analysis, and funnel plots used to deted publication bias.

RESULTS

Nineteen randomized controlled trials were included and 1510 patients involved. The treatment guided byTCM based on the liver was superior to Western Medicine [odds ratio (OR) = 2.46, 95% confidence interval (CI) 1.80, 3.35)], cure rate [OR = 2.61, 95% Cl (1.93, 3.52)], remarkable efficacy [OR = 2.68, 95% Cl (1.82, 3.95)], recurrence rate [OR = 0.19, 95% CI (0.12, 0.29)] and the incidence of adverse reactions [OR = 0.24, 95% CI (0.09, 0.65)]. However, funnel plots showed publication bias.

CONCLUSION

Compared with Western Medicine, the treatment of IBS-C based on the liver is significantly better but the results must be treated with caution because publication bias was recorded.

Diarrhoea is not the only symptom that needs to be treated in patients with microscopic colitis

BACKGROUND

Many patients with microscopic colitis (MC) also suffer from symptoms of irritable bowel syndrome (IBS), but the only treatment given is corticosteroids for the diarrhoea. The aim of this study was to examine how social factors, life style factors and drug treatment affect symptoms and well-being in patients suffering from MC.

METHODS

Women, over the age of 73years, with biopsy-verified MC, at any Departments of Gastroenterology, Skåne, between 2002 and 2010 were invited. The questionnaires Gastrointestinal Symptom Rating Scale (GSRS) and Psychological General Well-being Index (PGWB) were sent by mail, along with questions about social and life style factors, and medical history.

RESULTS

Of 240 invited, 158 patients (66%) were included (median age 63years, range 27-73years). Only 26% had never smoked. Smoking and concomitant IBS were associated with both impaired gastrointestinal symptoms (OR=3.96, 95% CI=1.47-10.66 and OR=4.40, 95% CI=2.09-9.26, respectively) and impaired psychological well-being (OR=2.77, 95% CI=1.04-7.34 and OR=3.82, 95% CI=1.83-7.99, respectively). Treatment with proton pump inhibitors (PPI) was associated with increased gastrointestinal symptoms (OR=3.44, 95% CI=1.45-8.16). Age, social factors, and corticosteroids had no effect on symptoms or well-being. Smoking was the only risk factor associated with IBS (OR=2.68, 95% CI=1.115-6.26).

CONCLUSION

Smoking and IBS are associated with impaired gastrointestinal symptoms and psychological well-being in MC patients. PPI is associated with impaired gastrointestinal symptoms.

Pathogenesis of irritable bowel syndrome--review regarding associated infection and immune activation

There is increasing evidence regarding the role of immune activation in the etiology of irritable bowel syndrome (IBS), which has been mainly been shown in studies investigating mechanisms of postinfectious IBS (PI-IBS). Exposure to intestinal infection induces persistent low-grade systemic and mucosal inflammation, which is characterized by an altered population of circulating cells, mucosal infiltration of immune cells and increased production of various cytokines in IBS patients. Recent studies have also indicated an increased innate immune response in these patients by evaluating expression and activation of Toll-like receptors (TLRs). These findings suggest that immune activation may play a crucial role in the pathogenesis of IBS. In addition, psychological stress has been reported to be one of the factors that induces immune activation. However, it remains unknown whether immune activation in IBS patients is largely dependent on infectious gastroenteritis and/or psychological stress. Additional studies are necessary to understand the precise mechanism of immune activation and its relationship to the development of IBS.

Low prevalence of 'classical' microscopic colitis but evidence of microscopic inflammation in Asian irritable bowel syndrome patients with diarrhoea

Background

There is increasing evidence for the role of microscopic inflammation in patients with IBS. We aimed to examine the prevalence of microscopic colitis and inflammation in Malaysian IBS patients with diarrhoea (IBS-D).

Methods

Consecutive patients who met the Rome III criteria for IBS-D and asymptomatic controls were prospectively recruited. Colonoscopy was performed in all study subjects and systematic biopsies taken from all segments of the colon. The diagnosis of lymphocytic colitis and collagenous colitis was made using previously defined criteria. Patients with post infectious IBS were excluded.

Results

120 subjects (74 IBS-D, 46 controls) were recruited during the study period. In the IBS-D group, the colonoscopic (macroscopic) findings were as follows; normal findings n = 58 (78.4%), diverticula disease n = 5 (6.8%), diminutive polyps n = 9 (12.2%) and haemorrhoids n = 2(2.7%). No subject under the age of 40 had any significant findings. Microscopically, there was only one case (1.3%) with histology consistent with collagenous colitis. However, the IBS-D patients had a higher prevalence of moderate microscopic inflammation (n = 11, 14.9%) compared to controls (n = 1, 2.2%) (p = 0.005).

Conclusions

‘Classical’ microscopic colitis is uncommon in Malaysian patients with IBS-D but a significant number of adults showed evidence of microscopic inflammation.

Rifaximin in irritable bowel syndrome: rationale, evidence and clinical use

Irritable bowel syndrome (IBS) is the most common functional bowel disease that affects up to 15% of the US population. The majority of patients with IBS have significant bloating and gas. Recent evidence is beginning to suggest that patients with IBS may have an alteration in the gastrointestinal flora. Specifically, findings suggest that patients with IBS have excessive bacteria in the small bowel, referred to as bacterial overgrowth. Therefore there may be benefits of antibiotic-based therapies for IBS. Rifaximin is a nonabsorbable antibiotic that demonstrates no clinically relevant bacterial resistance. Some studies have demonstrated the efficacy and durable improvement of IBS symptoms after treatment with rifaximin. In this review we explore the current data showing the association of small intestinal bacterial overgrowth (SIBO) and IBS as well as review the available data on the clinical use of rifaximin in the treatment of SIBO in patients with IBS.

Remarkable prevalence of coeliac disease in patients with irritable bowel syndrome plus fibromyalgia in comparison with those with isolated irritable bowel syndrome: a case-finding study

INTRODUCTION

Irritable bowel syndrome (IBS) and fibromyalgia syndrome (FMS) are two common central sensitization disorders frequently associated in the same patient, and some of these patients with IBS plus FMS (IBS/FMS) could actually be undiagnosed of coeliac disease (CD). The present study was an active case finding for CD in two IBS cohorts, one constituted by IBS/FMS subjects and the other by people with isolated IBS.

METHODS

A total of 104 patients (89.4% females) fulfilling the 1990 ACR criteria for FMS and the Rome III criteria for IBS classification and 125 unrelated age- and sex-matched IBS patients without FMS underwent the following studies: haematological, coagulation and biochemistry tests, serological and genetic markers for CD (i.e., tissue transglutaminase 2 (tTG-2) and major histocompatibility complex HLA-DQ2/HLA-DQ8), multiple gastric and duodenal biopsies, FMS tender points (TPs), Fibromyalgia Impact Questionnaire (FIQ), Health Assessment Questionnaire (HAQ), 36-Item Short Form Health Survey (SF-36) and Visual Analogue Scales (VASs) for tiredness and gastrointestinal complaints.

RESULTS

As a whole, IBS/FMS patients scored much worse in quality of life and VAS scores than those with isolated IBS (P < 0.001). Seven subjects (6.7%) from the IBS/FMS group displayed HLA-DQ2/HLA-DQ8 positivity, high tTG-2 serum levels and duodenal villous atrophy, concordant with CD. Interestingly enough, these seven patients were started on a gluten-free diet (GFD), showing a remarkable improvement in their digestive and systemic symptoms on follow-up.

CONCLUSIONS

The findings of this screening indicate that a non-negligible percentage of IBS/FMS patients are CD patients, whose symptoms can improve and in whom long-term CD-related complications might possibly be prevented with a strict lifelong GFD.

Treatment of irritable bowel syndrome: sex and gender specific aspects

Patients with functional gastrointestinal disorders constitute the majority of patients seeking healthcare for gastrointestinal symptoms in primary and secondary care. Of these disorders irritable bowel syndrome (IBS) is one of the most common and affects 10-20% in the Western world. IBS is a functional bowel disorder characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits in the absence of any detectable organic cause. Sex and gender aspects are important in understanding differences between men and women in their risk and experience of IBS. Relative to men, women are diagnosed more frequently with IBS. Female patients are more likely to be constipated, complain of abdominal distension and of certain extracolonic symptoms. Given the variability of IBS, the most successful treatment will be comprehensive, involving multiple strategies. Efficacy, safety and tolerability are important in the evaluation of IBS therapies, as patients are likely to require long-term treatment. Laxatives, antidiarrheals or antispasmodics are common in the treatment of IBS but the majority of patients receive antispasmodics followed by prokinetic agents. In treatment of IBS there appears to be a greater clinical response to serotonergic agents developed for IBS in women compared to men. There is an absence of drugs licensed specifically for the treatment of IBS. Further studies with novel agents are needed, to evaluate new approaches to IBS management including gender specific behavioral therapies and better characterization of patient subgroups with regard to drug therapy so that personalized therapy can be tested.

Gastrointestinal symptoms and psychological well-being in patients with microscopic colitis

OBJECTIVE

Microscopic colitis (MC) and irritable bowel syndrome (IBS) are both gastrointestinal disorders with female predominance that affect well-being. Autoantibodies against gonadotropin-releasing hormone (GnRH) have recently been detected in IBS patients. The purpose of this study was to compare gastrointestinal symptoms and well-being in MC female outpatients, with or without coexisting IBS-like symptoms, and to examine the prevalence of GnRH antibodies in these patients.

MATERIAL AND METHODS

Women with biopsy-verified MC, at any outpatient clinic of the Departments of Gastroenterology, Skåne, between 2002 and 2010 were invited to participate in the study. The questionnaires Gastrointestinal Symptom Rating Scale (GSRS), Psychological General Well-being Index (PGWB), Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS), and Rome III were answered and blood samples collected. Autoantibodies (IgG, IgA, and IgM) against GnRH and GnRH-R (extracellular peptide of receptor) were determined by an enzyme-linked immunosorbent assay.

RESULTS

Altogether, 158 (66%) of 240 invited patients with MC were recruited to the study. Of these, 133 (55%) patients also accepted to provide blood samples. Patients with IBS-like symptoms (55%) experienced more symptoms and worse psychological well-being in all dimensions in GSRS and PGWB, and in all symptoms but constipation in VAS-IBS compared to patients without IBS symptoms. Only a minority of patients expressed antibodies against GnRH or GnRH-R, which did not differ between groups.

CONCLUSIONS

MC patients fulfilling criteria for IBS experience more gastrointestinal symptoms and worse psychological well-being than those who do not. Autoantibodies against GnRH or GnRH-R are not frequently observed in MC patients.

Rifaximin treatment for the irritable bowel syndrome with a positive lactulose hydrogen breath test improves symptoms for at least 3 months

BACKGROUND

While rifaximin was able to improve symptoms in patients with irritable bowel syndrome (IBS) in phase III trials, these results are yet to be repeated in phase IV studies.

AIM

To evaluate the treatment response to rifaximin in IBS patients in a phase IV trial.

METHODS

IBS patients underwent lactulose hydrogen breath testing (LHBT). LHBT-positive patients were treated with rifaximin for 14 days. Prior to treatment as well as at week 4 and 14 following the start of rifaximin treatment, patients completed a questionnaire assessing symptom severity on a Likert scale from 0 to 10.

RESULTS

One hundred and six of 150 IBS patients (71%) were LHBT-positive and treated with rifaximin. As assessed at week 4 following commencement of the therapy, rifaximin provided significant improvement of the following IBS-associated symptoms: bloating (5.5 ± 2.6 before the start of the treatment vs. 3.6 ± 2.7 at week 4, P<0.001), flatulence (5.0 ± 2.7 vs. 4.0 ± 2.7, P=0.015), diarrhoea (2.9 ± 2.4 vs. 2.0 ± 2.4, P=0.005) and abdominal pain (4.8 ± 2.7 vs. 3.3 ± 2.5, P<0.001). Overall well-being also significantly improved (3.9 ± 2.4 vs. 2.7 ± 2.3, P < 0.001). Similar improvements in IBS symptoms were obtained at week 14. Eighty-six per cent of patients undergoing repetitive LHBT (55/64) tested negative at week 4.

CONCLUSIONS

We found a high percentage of LHBT-positive IBS patients. IBS-associated symptoms (bloating, flatulence, diarrhoea, pain) were improved for a period of 3 months following 2 weeks of treatment with rifaximin. We conclude that rifaximin treatment alleviates symptoms in LHBT-positive IBS patients.

Food patch testing for irritable bowel syndrome

BACKGROUND

The traditional classification of irritable bowel syndrome (IBS) as a functional disorder has been challenged in recent years by evidence of ongoing low-grade gastrointestinal tract inflammation. Inflammation may alter gastrointestinal motility and thus be central to the pathogenesis of IBS. Many foods and food additives are known to cause allergic contact dermatitis. We hypothesize that allergenic foods and food additives may elicit a similar allergic reaction in the gastrointestinal tract, giving rise to symptoms suggestive of IBS.

OBJECTIVE

We sought to determine whether skin patch testing to a panel of foods and food additives may identify food allergens that may be responsible for symptoms of IBS.

METHODS

We performed skin patch testing to common allergenic foods and food additives on individuals with a history of or symptoms suggestive of IBS. We used patch test-guided avoidance diets to determine whether avoidance alleviates IBS symptoms.

RESULTS

Thirty of the 51 study participants showed at least 1 doubtful or positive patch test result. Fourteen of the participants reported symptomatic improvement, ranging from slight to great, upon avoidance of the foods/food additives to which they reacted.

LIMITATIONS

Double-blind study design, inclusion of only patients with active IBS, larger sample size, more balanced gender distribution, testing of more foods/food additives, and longer duration of and more precise quantification of response to dietary avoidance are suggested for future studies.

CONCLUSION

Allergic contact enteritis to ingested foods, food additives, or both may contribute to IBS symptoms. Patch testing may be useful in identifying the causative foods.

Prevalence of organic colonic lesions in patients meeting Rome III criteria for diagnosis of IBS: a prospective multi-center study utilizing colonoscopy

BACKGROUND

It remains unknown whether the Rome III criteria can exclude organic colonic lesions prior to the diagnosis of irritable bowel syndrome (IBS). We evaluated the colonoscopy results of patients meeting the Rome III criteria for the diagnosis of IBS to determine the presence of organic colonic lesions.

METHODS

This study was prospectively conducted at 17 centers in Japan. We enrolled 4528 patients who underwent diagnostic colonoscopy examinations. The diagnosis of IBS was evaluated by questionnaire results according to the Rome III criteria.

RESULTS

We evaluated 4178 patients (350 were excluded because of incomplete data or previous colonic surgery), of whom 203 met the Rome III criteria (mean age 57.9 years; range 14-87 years) prior to the diagnostic colonoscopy examination. We identified organic colonic diseases in 21 of these 203 patients (10.3 %) , and these disease were also identified in 338 (8.5 %) of 3975 patients who did not fulfill the Rome III criteria. There were no differences in regard to the prevalence of organic colonic diseases between patients who did and did not fulfill the Rome III criteria.

CONCLUSIONS

The prevalence of organic colonic diseases in patients who met the Rome III criteria was at an acceptably low level, indicating that the Rome III criteria are adequately specific for the diagnosis of IBS without performing a colonoscopy examination.

Clinical features of symptomatic uncomplicated diverticular disease: a multicenter Italian survey

PURPOSE

Clinical features of symptomatic uncomplicated diverticular disease are poorly investigated. Abdominal symptoms may be similar to those of irritable bowel syndrome. This survey aimed to assess clinical features associated with symptomatic uncomplicated diverticular disease.

METHODS

This multicenter survey included consecutive outpatients with symptomatic uncomplicated diverticular disease to whom a detailed clinical questionnaire regarding demographic, lifestyle, and clinical features was administered. Diagnosis was based on the presence of diverticula and abdominal pain/discomfort. Irritable bowel syndrome and functional dyspepsia were assessed according to Rome III criteria.

RESULTS

A total of 598 patients (50 % female, age 69 years), 71 % with newly diagnosed symptomatic uncomplicated diverticular disease and 29 % with history of colonic diverticula, were recruited. Diverticula were localized in the left colon in 78 % of the patients. Recurrent short-lived abdominal pain (<24 h) was present in 70 % (relieved by evacuation in 73 %), prolonged abdominal pain (>24 h) in 27 %, and recurrent abdominal bloating in 61 % of the patients. Normal, loose, or hard stools were reported by 58, 29, and 13 % of patients, respectively. Irritable bowel syndrome (IBS)-like and functional dyspepsia-like symptoms were recorded in 59 and 7 % of patients, respectively. IBS-like symptoms (odds ratio, 4.3) were associated in patients with prolonged abdominal pain.

CONCLUSIONS

Symptomatic uncomplicated diverticular disease is associated with a gender ratio of 1:1 and an unspecific clinical picture mainly characterized by normal stools, short-lived abdominal pain, abdominal bloating, IBS-like symptoms, while functional dyspepsia-like symptoms are not commonly present. These findings suggest that symptomatic uncomplicated diverticular disease often shows similar findings rather than overlaps IBS.

Probiotics and irritable bowel syndrome

Background

Irritable bowel syndrome (IBS) is a major cause of abdominal discomfort and gut dysfunction worldwide. It is a poorly understood functional gastrointestinal disorder for which no effective medication is available. It is a benign condition, but its social and economic burden is significant. The symptoms consist of abdominal pain, bloating, flatulence, and irregular bowel movements. Alterations in the intestinal microbiota and mucosal inflammation may contribute to the development of IBS and probiotics could thus relieve the symptoms. This review gives an overview on the existing data on the effects of probiotics on the gastrointestinal symptoms of IBS.

Methods

A PUBMED search was made to review the relevant literature, and additional studies were obtained from the references of the selected articles.

Results

Clinical trials suggest that certain probiotics or combinations of bacteria have beneficial effects on the IBS symptoms. However the heterogeneity of studies, e.g. suboptimal study design, inadequate number of subjects, different doses and vehicles, inadequate length, make it difficult to compare the differences between probiotics and the effect may be strain-specific.

Conclusions

Though evidence is very promising, no general recommendations on the use of probiotics in IBS can be given yet. Further clinical trials and data on the mechanisms of action are needed. Probiotics are considered safe and if future scientific data is able to substantiate their efficacy in IBS, they certainly could be a treatment option in relieving the symptoms in IBS.

Irritable bowel syndrome and psychiatric disorders in pakistan: a case control study

Background. The psychiatric disorders like anxiety and depression could have a profound influence on onset, expression, and course of Irritable bowel syndrome (IBS). Aim. To estimate the frequency and strength of association of common mental disorders (CMDs) in patients with IBS and patients with other chronic diseases, that is, migraine and hypertension. Method. This was a case control study. Individuals aged 18-70 years diagnosed as IBS were enrolled as cases. The control groups consisted of patients without IBS but diagnosed to have a chronic disease, that is, migraine or HTN. Self-Reporting Questonnaire-20(SRQ-20) was used as a screening tool for the detection of CMD. Results. 82 patients were enrolled in each group. Mean SRQ score was significantly higher in IBS group than controls (9.9 ± 4.5 versus 4.9 ± 3.6, P < 0.001). CMDs were more frequent (67.1% versus 22%) and the odds of CMD were 7.24 times higher among IBS patients than controls (95% CI 3.6-14.5, P < 0.001). No difference was found in frequency of CMDs among various subtypes of IBS. Conclusion. We found that CMDs are more common and strongly associated with IBS as compared to other chronic diseases. Early screening for CMDs might be useful for an effective management of IBS.

Review article: probiotics for the treatment of irritable bowel syndrome--focus on lactic acid bacteria

BACKGROUND

Irritable bowel syndrome (IBS) is a poorly understood, yet highly prevalent functional gastrointestinal disorder (FGID). The withdrawal, due to adverse events, of a number of pharmacological agents that were approved for the treatment of IBS has left a therapeutic vacuum for patients suffering from the disorder.

AIM

To review, summarise and critically evaluate current knowledge of lactic acid bacteria (LAB) used to treat IBS.

METHODS

We assessed a comprehensive range of relevant literature from Pubmed, Medline and online sources based on our definition of LAB which included both typical and atypical species, covering Lactobacilli, Bifidobacteria, Enterococci, Streptococci and Bacilli.

RESULTS

Of the 42 trials evaluated examining the efficacy of LAB in IBS, 34 reported beneficial effects in at least one of the endpoints or symptoms examined, albeit with tremendous variation in both the magnitude of effect and the choice of outcome under consideration. However, numerous concerns have been expressed over deficits of trial design and execution relating to strain selection, optimum dosage, mode of action, safety and long-term tolerability in a disorder that can persist throughout the lifetime of affected individuals.

CONCLUSIONS

Progress in the field will require an improved understanding of how the microbiota impacts on health and disease, adequately powered long-term multicentre trials and the embracing of bench to bedside approaches. Recent incremental advances suggest these areas are being addressed and that the future holds much promise for the use of lactic acid bacteria in the treatment of irritable bowel syndrome.

Gut memories: towards a cognitive neurobiology of irritable bowel syndrome

The brain and the gut are engaged in continual crosstalk along a number of pathways collectively termed the 'brain-gut axis'. Over recent years it has become increasingly clear that dysregulation of the axis at a number of levels can result in disorders such as irritable bowel syndrome (IBS). With recent advances in neuroimaging technologies, insights into the neurobiology of IBS are beginning to emerge. However the cognitive neurobiology of IBS has remained relatively unexplored to date. In this review we summarise the available data on cognitive function in IBS. Moreover, we specifically address three key pathophysiological factors, namely; stress, immune activation and chronic pain, together with other factors involved in the manifestation of IBS, and explore how each of these components may impact centrally, what neurobiological mechanisms might be involved, and consider the implications for cognitive functioning in IBS. We conclude that each factor addressed could significantly impinge on central nervous system function, supporting the view that future research efforts must be directed towards a detailed assessment of cognitive function in IBS.

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.

METHODS

The study subjects, based in Olmsted County, MN, reported symptoms of functional dyspepsia or IBS (n = 69), or were asymptomatic controls (n = 64). Their coded sera were screened for antibodies targeting neuronal, glial, and muscle autoantigens.

RESULTS

The prevalence of neural autoantibodies with functional GI disorders did not differ significantly from controls (17% vs. 13%; P = 0.43). In no case was a neuronal or glial nuclear autoantibody or enteric neuronal autoantibody identified. Neuronal cation channel antibodies were identified in 9% of cases (voltage-gated potassium channel [VGKC] in one dyspepsia case and one IBS case, ganglionic acetylcholine receptor [AChR] in four IBS cases) and in 6% of controls (ganglionic AChR in one, voltage-gated calcium channel [VGCC], N-type, in two and VGKC in one; P = 0.36). The frequency of glutamic acid decarboxylase-65 (GAD65) autoantibodies was similar in cases (10%) and controls (5%; P = 0.23).

CONCLUSIONS

Our data do not support neural autoimmunity as the basis for most IBS or functional dyspepsia cases.

Functional gastrointestinal disorders in inflammatory bowel disease: impact on quality of life and psychological status

BACKGROUND AND AIM

In inflammatory bowel disease (IBD), ongoing gastrointestinal (GI) symptoms consistent with coexistent functional GI disorders (FGID) might occur. It is uncertain what effect these symptoms have on health-related quality of life (HRQoL) and psychological comorbidity. The aim of the present study was to identify interrelationships among IBD, symptoms consistent with FGID, HRQoL, and psychological comorbidity.

METHODS

A total of 256 consecutive IBD patients had diagnoses and disease activity verified at case-note review. Patients completed a contemporaneous survey assessing HRQoL, anxiety/depression, and GI symptoms (classified by Rome III criteria).

RESULTS

Of 162 respondents (response rate: 63%), 95 (58.6%) had Crohn's disease and 63 (38.8%) had ulcerative colitis. By Rome III criteria, 66% met criteria for at least one FGID. Those with significant (Hospital Anxiety and Depression Scale ≥ 8) anxiety and/or depression were more likely to meet criteria for coexistent FGID (78% vs 22% and 89% vs 11%, respectively; each P < 0.001). A "load effect" was noted, such that the number of symptoms consistent with FGID in each patient correlated positively with anxiety and depression and negatively with HRQoL. Symptoms of any coexistent FGID were highly prevalent, even in those with currently-inactive IBD (57%).

CONCLUSIONS

Symptoms consistent with FGID are highly prevalent in IBD and correlate with greater psychological comorbidity and poorer HRQoL in a "load-dependent" fashion. Therapy directed either at symptom load or psychological comorbidity might independently improve HRQoL in IBD.

High-dose rifaximin treatment alleviates global symptoms of irritable bowel syndrome

Background:

To evaluate the efficacy of rifaximin for reduction of gastrointestinal symptoms in patients with irritable bowel syndrome (IBS).

Methods:

Medical records were identified for consecutive patients diagnosed with IBS according to Rome III criteria, who had abnormal lactulose breath test results and had received rifaximin 1200 mg/day for 10 days. The efficacy of rifaximin for reducing gastrointestinal symptoms and for eradicating small intestinal bacterial overgrowth was ascertained in these patients. In addition, these endpoints were examined in patients who were initially unresponsive to rifaximin 1200 mg/day and received subsequent rifaximin 2400 mg/day.

Results:

Patients who received rifaximin 1200 mg/day (n = 162) experienced a mean improvement of 52% in global IBS symptoms at the end of rifaximin treatment. Similarly, initially unresponsive patients who received additional rifaximin 2400 mg/day (n = 81) experienced a 53% mean improvement in global IBS symptoms. Forty-nine percent of patients who received initial rifaximin and 47% of patients who received high-dose rifaximin achieved ≥50% global symptom improvement during at least one follow-up visit. Normalization of lactulose breath test results was only apparent in some patients who received high-dose rifaximin. Rifaximin was well tolerated.

Conclusion:

Rifaximin 1200 mg/day for 10 days reduced gastrointestinal symptoms in patients with IBS. Patients with incomplete symptom resolution may respond to increased doses of rifaximin.

Irritable bowel syndrome

Questions from patients about analgesic pharmacotherapy and responses from the authors are presented to help educate patient sand make them more effective self-advocates. The topics addressed in this issue are the signs, symptoms, and treatment of irritable bowel syndrome (IBS). A discussion of pain management and complementary therapies is included.

Effects of antidepressants in patients with irritable bowel syndrome and comorbid depression

BACKGROUND

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that affects up to 15% of community dwelling individuals. Psychiatric comorbidities, particularly symptoms of major depressive disorder (MDD), occur in up to 90% of patients with IBS.

OBJECTIVE

This article reviews the available literature on the use of antidepressants for both IBS and psychiatric depressive symptoms in patients with IBS.

METHODS

MEDLINE and International Pharmaceutical Abstracts (both, 1980-May 2010) were searched for English-language publications that involved antidepressant treatment of MDD in patients with IBS. The search terms were depression, irritable, bowel, treatment, and functional. The reference lists of key articles were searched for additional pertinent articles. Randomized controlled trials published in the past 10 years were given priority.

RESULTS

Of 46 articles identified by the literature search, 11 were included in the review: 4 studies of selective serotonin reuptake inhibitors (SSRIs), 4 of tricyclic antidepressants (TCAs), 1 comparing an SSRI and a TCA, 1 of the serotonin-norepinephrine reuptake inhibitor duloxetine, and a case report involving the tetracyclic antidepressant mirtazapine. Most of the identified studies excluded patients with a diagnosis of depression and/or anxiety. No controlled studies were identified in which the primary outcome was objective assessment of MDD symptoms in patients with IBS. Two of the SSRI studies, one of citalopram and the other of paroxetine, reported approximately 50% improvement in IBS symptoms (both studies, P = 0.01); the study of paroxetine reported a 30% improvement in scores on the Beck Depression Inventory (P = 0.01). The 2 studies of fluoxetine found no statistically significant benefit on IBS symptoms. TCAs were reported to have benefits on IBS symptoms, predominantly diarrhea. Only one of the TCA studies examined and found a significant improvement in depressive symptoms with desipramine 150 mg/d (P = 0.025). Both the open-label study of duloxetine and the case report involving mirtazapine found improvements in IBS and psychiatric symptoms.

CONCLUSIONS

The evidence for the benefit of antidepressant treatment in patients with IBS and comorbid depression was limited and contradictory. Some anti-depressants may help symptoms of IBS, although whether the same drugs and doses are associated with improvements in concomitant depressive symptoms remains to be elucidated.

Comparison of methods for detection of Blastocystis infection in routinely submitted stool samples, and also in IBS/IBD Patients in Ankara, Turkey

Background

This study compared diagnostic methods for identifying Blastocystis in stool samples, and evaluated the frequency of detection of Blastocystis in patients with irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).

Results and Discussion

From a set of 105 stool specimens submitted for routine parasitological analysis, 30 were identified as positive for Blastocystis by the culture method. From that group of 30 positives, Lugol's stain, trichrome staining, and an immunofluorescence assay identified 11, 15, and 26 samples as positive respectively. Using culture as a standard, the sensitivity of Lugol's stain was 36.7%, trichrome staining was 50%, and the IFA stain was 86.7%. The specificity of Lugol's stain was 91%, trichrome staining was 100%, and the IFA stain was 97.3%. In the group of 27 IBS and IBD patients, using all methods combined, we detected Blastocystis in 67% (18/27) of the patients. Blastocystis was detected in 33% (2/6) of IBD patients and 76% (16/21) of IBS patients. For comparison, trichrome staining alone, the method most frequently used in many countries, would have only identified Blastocystis infection in 29% (6/21) of the IBS patients. No parasitic co-infections were identified in the IBS/IBD patients. Most Blastocystis-positive IBS/IBD patients were over 36 with an average length of illness of 4.9 years.

Conclusions

Most IBS patients in this study were infected with Blastocystis. IFA staining may be a useful alternative to stool culture, especially if stool specimens have been chemically preserved.

Is there an overlap between irritable bowel syndrome and appendicopathy syndrome? A new theory

BACKGROUND AND AIMS

The costs of irritable bowel syndrome are huge - personally, socially and financially. Yet despite numerous articles on the subject, an effective treatment seems far away. The hypothesis to be offered in this paper is: that a (laparoscopic) appendicectomy could also be useful in treating at least some of the patients with IBS. Using data I have collected from my own surgery practice over a number of years, I will demonstrate the link between the effective treatment of appendicitis by laparoscopic appendectomy and propose that this could also be a useful treatment for some cases of IBS. The study of symptoms of IBS showed that it shared several of the symptoms found in appendicopathy. The aim of this study is: (1) to confirm the cure rate of the laparoscopic appendectomy in cases of appendicopathy, (2) to determine the overlap of symptoms and (3) examine a new theory - that some cases of IBS originate in the appendix.

SUPPORTING DATA

Two succeeding series of patients sent to me for possible appendicopathy were treated with laparoscopic appendectomy if their list of symptoms suggested this was appropriate. The first series comprised 114 patients. The results prompted a second series of 126 patients. This second group was primarily set up to confirm the results obtained from the first group. In our material we found statistical evidence that both groups were comparable indeed. Both groups suffered from not only pain, but also other side effects: indigestion, problems with exercise, feelings of stress, defecation disorders, disuria and loss of energy. The favourable results of the second series were roughly the same as those of the first one. Not only were about 80% of the patients pain free after 6 months or less, but the co-morbidity was gone in about 80% of the patients as well. In the literature, there are several reports describing a favourable outcome of appendicectomy for appendicopathy. Especially positive was one of only a few randomised, double-blinded, placebo controlled, parallel group trials in the history of surgery (Roumen, cs), which proved that "persistent or recurrent lower abdominal pain can be treated by elective appendicectomy with significant pain reduction in properly selected cases". An important part of the symptoms of both syndromes do overlap: (1) pain in the abdomen, varying in strength and more pain after a large meal, (2) changing bowel habits between constipation and diarrhoea, (3) indigestion and (4) stress.

CONCLUSION

Taking into account the overlap in several symptoms between IBS and Appendicopathy there is a possibility that both syndromes originate (partly) in the appendix and therefore laparoscopy and appendicectomy may play a part in the treatment of IBS as well. Pilot studies in this direction seem to be indicated.

Clinical trial: the efficacy of alverine citrate/simeticone combination on abdominal pain/discomfort in irritable bowel syndrome--a randomized, double-blind, placebo-controlled study

BACKGROUND

Alverine citrate and simeticone combination has been used for almost 20 years in irritable bowel syndrome (IBS), but supportive scientific evidence of efficacy was limited.

AIM

To evaluate the efficacy of alverine citrate and simeticone combination in patients with IBS-related abdominal pain/discomfort.

METHODS

A total of 412 IBS patients meeting ROME III criteria were included in this double-blind randomized placebo-controlled study if their abdominal pain/discomfort intensity was at least 60 mm on a 0-100 mm visual analogue scale (VAS) during a 2-week run-in treatment-free period. Patients were randomly assigned through the use of Interactive Voice Response System to receive either alverine citrate 60 mg with simeticone 300 mg three times daily or matching placebo for 4 weeks.

RESULTS

The full analysis set included 409 patients (71.4% female: mean age: 46.2 +/- 13.9 years). At week 4, alverine citrate and simeticone group had lower VAS scores of abdominal pain/discomfort (median: 40 mm vs. 50 mm, P = 0.047) and higher responder rate (46.8% vs. 34.3%, OR = 1.3; P = 0.01) as compared with placebo group. Patient receiving alverine citrate and simeticone reported greater global symptom improvement compared with those receiving placebo (P = 0.0001). Reported adverse events were similar in both groups.

CONCLUSION

Alverine citrate/simeticone combination was significantly more effective than placebo in relieving abdominal pain/discomfort in patients with IBS.

Diarrhea-predominant irritable bowel syndrome is associated with diverticular disease: a population-based study

OBJECTIVES

A subset of patients with colonic diverticular disease have chronic gastrointestinal symptoms, and some have a clinical diagnosis of irritable bowel syndrome (IBS), but whether IBS and diverticular disease are linked is uncertain. We aimed to evaluate this association in the community.

METHODS

A population-based, cross-sectional survey was conducted by mailing a valid symptom questionnaire to the eligible residents of Olmsted County, MN, aged 30-95 years. Colonic diverticular disease (diverticulosis and diverticulitis) was ascertained through a review of the complete medical history of all responders. Subjects with at least one relevant test (colonoscopy, computed tomography (CT) scan, CT colonography, or barium enema) were included. IBS was defined using Rome II criteria.

RESULTS

Among 2,267 eligible respondents, there were 1,712 subjects who had undergone colon testing (76%): 919 women (54%); mean (+/-s.d.) age 65 (+/-11 years). Colonic diverticular disease was identified in 44.4% (95% confidence interval (CI) 42.1-46.8) of the subject. IBS was reported by 8.8% (95% CI 6.9-11.0) of men and 17.0% (95% CI 14.6-19.6) of women. After adjusting for age and gender, the presence of IBS was associated with an increased odds for diverticulosis (odds ratio (OR) =1.8, 95% CI 1.3-2.4) but not diverticulitis (OR=1.7, 95% CI 0.9-3.2). In those 65 years of age or older, the presence of IBS was associated with a ninefold higher odds for diverticulosis (OR=9.4, 95% CI 5.8-15.1). Relative to the non-IBS subgroup, diarrhea-predominant IBS and mixed IBS were significantly associated with an increased odds for diverticular disease (OR=1.9, 95% CI 1.1-3.2; OR=2.6, 95% CI 1.0-6.4, respectively).

CONCLUSIONS

There is a significantly increased odds for colonic diverticulosis in subjects with IBS (relative to those without IBS). These results suggest that IBS and colonic diverticular disease may be connected.

Effect of electro-acupuncture on substance P, its receptor and corticotropin-releasing hormone in rats with irritable bowel syndrome

AIM: To investigate the effect and mechanism of electro-acupuncture (EA) at ST25 and ST37 on irritable bowel syndrome (IBS) of rats.

METHODS: A total of 21 male Sprague-Dawley rats were randomly divided into normal group, model group and EA group. A rat model of IBS was established by constraining the limbs and distending the colorectum of rats. Rats in EA group received bilateral EA at ST25 and ST37 with a sparse and intense waveform at a frequency of 2/50 Hz for 15 min, once a day for 7 d as a course. Rats in normal and model groups were stimulated by distending colorectum (CR). An abdominal withdrawal reflex (AWR) scoring system was used to evaluate improvements in visceral hypersensitivity. Toluidine blue-improved method, immunohistochemistry and radioimmunoassay were used to observe mucosal mast cells (MC), changes of substance P (SP) and substance P receptor (SPR) in colon and change of corticotropin-releasing hormone (CRH) in hypothalamus.

RESULTS: The threshold of visceral sense was significantly lower in model group than in normal group, and significantly higher in EA group than in model group. The number of mucosal MC was greater in model group than in normal group and significantly smaller in EA group than in model group. The CRH level in hypothalamus of rats was significantly higher in model group than in normal group, which was remarkably decreased after electro-acupuncture treatment. The SP and SPR expression in colon of rats in model group was decreased after electro-acupuncture treatment.

CONCLUSION: EA at ST25 and ST37 can decrease the number of mucosal MC and down-regulate the expression of CRH in hypothalamus, and the expression of SP and SPR in colon of rats with IBS.

Irritable bowel syndrome: towards biomarker identification

Irritable bowel syndrome (IBS), the most common functional gastrointestinal disorder referred to gastroenterologists, affects 7-10% of the general population worldwide. The lack of suitable disease-defining biological markers coupled with a poorly understood underlying pathophysiology complicates patient diagnosis and seriously hampers drug discovery efforts. Over the past few years, a number of potential biomarkers have emerged, and in this review we critically evaluate such candidates. In particular, we highlight the increasing number of studies supporting a low-grade immune activation in IBS and consider how the latest preclinical developments can contribute to the development of more robust and reliable biological markers of this disorder. The successful identification of biomarkers is critical to progressing our understanding of IBS and addressing the unmet therapeutic needs of this debilitating condition.

The gastrointestinal microbiome: a malleable, third genome of mammals

The nonpathogenic, mutualistic bacteria of the mammalian gastrointestinal tract provide a number of benefits to the host. Recent reports have shown how the aggregate genomes of gastrointestinal bacteria provide novel benefits by functioning as the third major genome in mammals along with the nuclear and mitochondrial genomes. Consequently, efforts are underway to elucidate the complexity of the organisms comprising the unique ecosystem of the gastrointestinal tract, as well as those associated with other epidermal surfaces. The current knowledge of the gastrointestinal microbiome, its relationship to human health and disease with a particular focus on mammalian physiology, and efforts to alter its composition as a novel therapeutic approach are reviewed.

A novel herbal preparation desensitizes mesenteric afferents to bradykinin in the rat small intestine

Herbal preparations are evolving as promising agents for the treatment of functional gastrointestinal disorders which are considered to be secondary to visceral hypersensitivity. We aimed to determine whether a new combination of six herbal extracts reduces the sensitivity of intestinal afferents in rat. Male Wistar rats (250-350 g, n = 6 per group) were gavaged with either vehicle or 2.5, 5 or 10 mL kg(-1) of STW 5-II, a herbal preparation which contains six extracts. Two hours later, animals were anaesthetized and extracellular multi-unit mesenteric afferent nerve recordings were obtained in the proximal jejunum in vivo. Afferent discharge to 5-hydroxy-tryptamine (5-HT) (5, 10, 20 and 40 microg kg(-1), i.v.), luminal distension (0-60 mmHg) and bradykinin (BK) (15, 30 and 60 microg kg(-1), i.v.) was recorded. At baseline, spontaneous afferent discharge was not different following pretreatment with the various doses of STW 5-II compared with vehicle. The pressure-dependent increase in afferent discharge to intraluminal ramp distension and the dose-dependent increase in afferent firing following 5-HT were also uninfluenced by STW 5-II pretreatment. In contrast, the afferent nerve responses to 15, 30 and 60 microg kg(-1) of BK were reduced following 10 mL kg(-1) STW 5-II with peaks at 106 +/- 19, 153 +/- 22 and 156 +/- 25 imp s(-1) compared with 160 +/- 15, 228 +/- 14 and 220 +/- 16 imp s(-1) following vehicle pretreatment (mean +/- SEM, P < 0.05). Intestinal afferent sensitivity to BK which plays a prime role in nociception was reduced following STW 5-II. Thus, STW 5-II may be of therapeutic use for conditions that involve neuronal hypersensitivity and the release of BK in the intestine.

Duodenal mastocytosis, eosinophilia and intraepithelial lymphocytosis as possible disease markers in the irritable bowel syndrome and functional dyspepsia

BACKGROUND

Irritable bowel syndrome (IBS) and functional dyspepsia (FD) are common functional disorders without defined pathology. Mast cells and eosinophils interact with T lymphocytes and may alter enteric nerve and smooth muscle function.

AIM

To examine mast cell, eosinophil and intraepithelial lymphocyte populations in duodenal biopsies of subjects with IBS and FD.

METHODS

A random sample of an adult Swedish population (n = 1001; mean age 54 years; 51% female) underwent upper endoscopy and biopsy; 51 cases with FD and 41 cases with IBS were compared with 48 randomly selected controls. Eosinophils were identified by light microscopy; mast cells by immunocytochemistry (CD117). Intraepithelial lymphocytes were counted per 100 enterocytes. Cell counts were quantified by counting the number per high power field (HPF) in 5HPFs in the bulb (D1) and second part of duodenum (D2), summed over 5HPFs at each site.

RESULTS

Cases and controls showed similar demographics. Compared to controls, IELs in IBS-constipation were significantly increased (P = 0.005). Mast cells were significantly increased in IBS in D2 (P < 0.001), while eosinophils were significantly increased in FD in D1 and D2 (P < 0.001).

CONCLUSION

Duodenal mast cell hyperplasia is linked to IBS and eosinophilia to FD, and duodenal biopsy may identify subsets of these disorders.

Adequate relief in a treatment trial with IBS patients: a prospective assessment

OBJECTIVES

Adequate relief (AR) of irritable bowel syndrome (IBS) symptoms (IBS-AR) has been used as a primary end point in many randomized controlled trials of IBS and is considered by the Rome III committee to be an acceptable primary end point. However, controversy exists on whether baseline severity confounds the effect of the treatment outcome. The aim (1) is to compare a subjective report of IBS-AR with global assessment of improvement (IBS-GAI), change in IBS symptom severity scale (IBS-SSS), and IBS quality of life (IBS-QOL); (2) to explore whether initial IBS symptom severity influences the ability of these outcome measures to detect differences post treatment; and (3) to determine whether psychological symptoms influence the sensitivity of these measures, in a randomized controlled treatment trial.

METHODS

A total of 289 adult IBS patients were recruited to a treatment trial. Baseline IBS-SSS scores were used to classify IBS severity as mild (<175), moderate (175-300), or severe (>300). Questionnaires were completed at baseline and after 3 weeks of treatment with sham acupuncture or wait-list control.

RESULTS

IBS baseline severity (IBS-SSS) significantly affected the proportion of patients who reported IBS-AR at 3 weeks (mild, 70%; moderate, 49.7%; severe, 38.8%) (P<0.05). However, once the patients who reported IBS-AR at baseline (28.0%) were excluded from the analysis, baseline severity no longer affected the proportion of patients reporting IBS-AR. Baseline severity did not have a significant effect on patients reporting moderate or significant improvement on the IBS-GAI (mild, 30%; moderate, 25.3%; severe, 18.8%) (P=NS). Psychological symptoms had no significant correlations with responders after adjusting for baseline severity.

CONCLUSIONS

These data suggest that IBS-AR as an end point is inversely related to baseline symptom severity. However, if patients who report AR at screening were excluded from study participation, baseline symptom severity was no longer confounded with a report of AR at the study end point.

Irritable bowel syndrome and inflammatory bowel disease: infectious gastroenteritis-related disorders?

Infectious gastroenteritis may be one of the important factors in the development of irritable bowel syndrome (IBS), with affected individuals often categorized as having post-infectious IBS (PI-IBS), and is linked to the onset of symptoms in approximately 10-20% of patients diagnosed with IBS. Intestinal mucosal infiltration of T cells and mast cells, and enterochromaffin cell hyperplasia are significant immunological and pathological findings that reveal the pathogenesis of PI-IBS, and results of laboratory studies using animal models of PI-IBS clearly support clinical evidence. Recently, infectious gastroenteritis has also been suggested to be associated with the development of inflammatory bowel disease (IBD), and various studies have suggested that individuals with IBS or IBS-like symptoms may be susceptible to initiation of IBD. However, it is still unclear whether infectious gastroenteritis is directly or indirectly (through PI-IBS) linked to the initiation of IBD. Additional studies are necessary to understand the clinical overlap among infectious gastroenteritis, IBS, and IBD.