New pathophysiological mechanisms in irritable bowel syndrome

Identification of Arginine-Vasopressin Receptor 1a (Avpr1a/Avpr1a) as a Novel Candidate Gene for Chronic Visceral Pain Sheds Light on the Potential Role of Enteric Neurons in the Development of Visceral Hypersensitivity

Chronic abdominal pain in the absence of ongoing disease is the hallmark of disorders of gut-brain interaction (DGBIs), including irritable bowel syndrome (IBS). While the etiology of DGBIs remains poorly understood, there is evidence that both genetic and environmental factors play a role. In this study, we report the identification and validation of arginine-vasopressin receptor 1A (Avpr1a) as a novel candidate gene for visceral hypersensitivity (VH), a primary peripheral mechanism underlying abdominal pain in DGBI/IBS. Comparing 2 C57BL/6 (BL/6) substrains (C57BL/6NTac and C57BL/6J) revealed differential susceptibility to the development of chronic VH following intrarectal zymosan instillation, a validated preclinical model for postinflammatory IBS. Using whole-genome sequencing, we identified a single-nucleotide polymorphism differentiating the 2 strains in the 5' intergenic region upstream of Avpr1a, encoding the protein Avpr1a. We used behavioral, histological, and molecular approaches to identify distal colon-specific gene expression and neuronal hyperresponsiveness covarying with Avpr1a genotype and VH susceptibility. While the 2 BL/6 substrains did not differ across other gastrointestinal phenotypes (eg, fecal water retention), VH-susceptible BL/6NTac mice had higher colonic Avpr1a mRNA and protein expression. These results parallel findings that patients' colonic Avpr1a mRNA expression corresponded to higher pain ratings. Moreover, neurons of the enteric nervous system were hyperresponsive to the Avpr1a agonist arginine-vasopressin, suggesting a role for enteric neurons in the pathology underlying VH. Taken together, these findings implicate differential regulation of Avpr1a as a novel mechanism of VH susceptibility as well as a potential therapeutic target specific to VH. PERSPECTIVE: This article presents evidence of Avpr1a as a novel candidate gene for VH in a mouse model of IBS. Avpr1a genotype and/or tissue-specific expression represents a potential biomarker for chronic abdominal pain susceptibility.

Not a general, symptom-unspecific, transdiagnostic marker for functional symptoms: sensorimotor processing of head control is intact in chronic pain

Introduction

Functional disorders are prevalent in all medical fields and pose a tremendous public health problem, with pain being one of the most common functional symptoms. Understanding the underlying, potentially unifying mechanism in functional (pain) disorders is instrumental in facilitating timely diagnosis, stigma reduction, and adequate treatment options. Neuroscientific models of perception suggest that functional symptoms arise due to dysregulated sensorimotor processing in the central nervous system, with brain-based predictions dominating the eventual percept. Experimental evidence for this transdiagnostic mechanism has been established in various functional symptoms. The goal of the current study was to investigate whether erroneous sensorimotor processing is an underlying transdiagnostic mechanism in chronic (functional) pain.

Method

A total of 13 patients with chronic (functional) pain [three patients with chronic (functional) pain disorder, F45.40, ICD-10; 10 patients with chronic pain disorder with somatic and psychological factors, F45.41, ICD-10]; and 15 healthy controls performed large combined eye-head gaze shifts toward visual targets, naturally and with increased head moment of inertia. We simultaneously measured participants' eye and head movements to assess head oscillations at the end of the gaze shift, which are an established indicator of (transdiagnostic) sensorimotor processing deficits of head control.

Results

Using a Bayesian analysis protocol, we found that patients with chronic (functional) pain and control participants stabilized their heads equally well (Bayes Factor 01 = 3.7, Bayes Factor exclusion = 5.23; corresponding to substantial evidence) during all sessions of the experiment.

Conclusion

Our results suggest that patients with chronic (functional) pain do not show measurable symptom-unspecific sensorimotor processing deficits. We discuss outcome parameter choice, organ system specificity, and selection of patient diagnoses as possible reasons for this result and recommend future avenues for research.

The efficacy and neural mechanism of acupuncture therapy in the treatment of visceral hypersensitivity in irritable bowel syndrome

Irritable Bowel Syndrome (IBS) is a complex functional gastrointestinal disorder primarily characterized by chronic abdominal pain, bloating, and altered bowel habits. Chronic abdominal pain caused by visceral Hypersensitivity (VH) is the main reason why patients with IBS seek medication. Significant research effort has been devoted to the efficacy of acupuncture as a non-drug alternative therapy for visceral-hyperalgesia-induced IBS. Herein, we examined the central and peripheral analgesic mechanisms of acupuncture in IBS treatment. Acupuncture can improve inflammation and relieve pain by reducing 5-hydroxytryptamine and 5-HT3A receptor expression and increasing 5-HT4 receptor expression in peripheral intestinal sensory endings. Moreover, acupuncture can also activate the transient receptor potential vanillin 1 channel, block the activity of intestinal glial cells, and reduce the secretion of local pain-related neurotransmitters, thereby weakening peripheral sensitization. Moreover, by inhibiting the activation of N-methyl-D-aspartate receptor ion channels in the dorsal horn of the spinal cord and anterior cingulate cortex or releasing opioids, acupuncture can block excessive stimulation of abnormal pain signals in the brain and spinal cord. It can also stimulate glial cells (through the P2X7 and prokinetic protein pathways) to block VH pain perception and cognition. Furthermore, acupuncture can regulate the emotional components of IBS by targeting hypothalamic-pituitary-adrenal axis-related hormones and neurotransmitters via relevant brain nuclei, hence improving the IBS-induced VH response. These findings provide a scientific basis for acupuncture as an effective clinical adjuvant therapy for IBS pain.

Serum Levels of Interferon Gamma INF-γ and Interleukin 10 Il-10: an Immunological Aspect among Irritable Bowel Syndrome Patients

BACKGROUND AND OBJECTIVE

The pathophysiological mechanisms of irritable bowel syndrome are controversial and the exact mechanism that play role in exaggeration of symptoms is mysterious. As an altered immunological functions in IBS patients may play role to study pro and anti-inflammatory cytokines among the study population. The aim of this study is to examine the serum cytokines of IL 10 and INFγ profile among a group of IBS patients and control.

MATERIALS AND METHODS

A cross sectional prospective study was conducted among 40 participants, who were referred to gastroenterology out patients clinics at Khartoum Teaching Hospital, Khartoum State, Sudan. Five milliliters blood were collected in EDTA tubes for measuring levels of cytokines in serum. Cytokines were measured by ELISA-MSD (Meso Scale Discovery). They were measured according to the manufacturer's instructions and expressed as pg mL-1. Optical density was measured at a wavelength of 450 nm and a reference wavelength of 590 nm.

RESULTS

Out of 16 (40%) male and 24 (60%) female, their age group range between 20-70 years old. The majority of them 21(52.5%) in age group (31-50) years old. Overall IBS patients showed significantly increased (p = 0.0001) of INF-γ (29.50±17.98 vs. 6.9±1.724 pg mL-1) between patients and control, respectively. The serum levels of IL-10 was significantly higher in patients with IBS compared with control group (p = 0.001).

CONCLUSION

There is an abnormal immune regulation, supporting the presence of immune activation in IBS.

Comparative effectiveness of 5-hydroxytryptamine 3 receptor antagonists in irritable bowel syndrome: a network meta-analysis of randomized controlled studies

BACKGROUND

There is evidence demonstrating the beneficial effects of 5-hydroxytryptamine 3 receptor antagonists (5-HT3) for the treatment of non-constipated irritable bowel syndrome (NC-IBS). We aimed to determine the comparative effectiveness of 5-HT3 antagonists in NC-IBS, as evidenced by the results of a network meta-analysis (NWM) of published relevant randomized controlled trials (RCTs).

METHODS

We searched the PubMed/Medline, EMBASE, and Cochrane Library databases for relevant RCTs through September 2020 and data from each selected RCT were extracted. A Bayesian NWM was then performed to investigate the efficacy of 5-HT3 antagonists and to explore the effectiveness rank order in treating NC-IBS patients.

RESULTS

Twenty-one eligible RCTs were identified and entered into this NWM. They included a total of 10,421 NC-IBS patients, randomized to alosetron, cilansetron, ondansetron, ramosetron, placebo, and mebeverine. The cumulative ranking probability for each intervention at the end of treatment period, was evaluated by means of surfaces under cumulative ranking (SUCRA) values. These results showed that alosetron had the best performance for global symptom improvement (SUCRA 0.82), cilansetron showed the best performance (SUCRA 0.90) for abdominal pain/discomfort improvement, while ondansetron (SUCRA 0.98) was by far the best choice concerning bowel habits/consistency improvement. The control regimens (mebeverine and placebo) represented the least efficacious interventions.

CONCLUSIONS

This NWM showed that 5-HT3 receptor antagonists performed better in comparison to control drugs. Consequently, this class of drugs may play an important role in improving the debilitating symptoms in NC-IBS patients, in particular those with diarrhea.

Irritable Bowel Syndrome: News from an Old Disorder

Irritable bowel syndrome (IBS) is a functional gastrointestinal (GI) disorder, which can affect all members of a society, regardless of age, sex, race or socioeconomic status. Because of its high prevalence and chronic nature, it represents a significant economic burden. In fact, these patients have a relevant impairment of their quality of life, which limits their work productivity and daily social activities, especially when it is associated with other disorders, such as anxiety and depression. The diagnosis of IBS relies on symptom-based diagnostic criteria with normal results on a limited number of complementary tests that rule out other possible diagnoses. The aetiology of this condition is incompletely established. However, evidence suggests that it is a multifactorial disorder with several different mechanisms that have been implicated as responsible for the symptoms. Since the treatment strategy is usually based on predominant symptoms and their severity, it is important to recognise the underlying mechanisms in order to successfully relief the visceral pain and altered bowel habits. The aim of this non-systematic review of the literature was to explore the pathophysiology and treatment options of IBS, highlighting the most recent evidence, from the new Rome IV criteria to the new drug armamentarium.

Phenotypic features of patients with post-infectious irritable bowel syndrome

Background

Although there are many published data in the literature about irritable bowel syndrome (IBS), there are only few data on the long term evolution of patients with post infectious irritable bowel syndrome (PI-IBS) and associated conditions.

Aims

The purpose of our research was to study the evolution of PI-IBS patients in a single tertiary center over a period of four years.

Study Design

Our research was a longitudinal retrospective study.

Methods

We carried out this study based on the survey of the patients records. We recruited two groups of patients: patients with classical IBS and patients with PI-IBS. The IBS diagnosis was established using ROME III criteria, which were used at that time. We compared the two groups of patients by analyzing the demographic data, comorbidities, treatment that was prescribed, and evolution after treatment for a period of 48 month on average.

Results

From a total of 592 patients that were diagnosed with IBS between 2013-2016, we identified a subgroup of 64 patients with PI-IBS. These patients were also divided into two subgroups, depending on the main symptoms, 51 with PI-IBS - diarrhea and 13 of them with PI-IBS-constipation. IBS is the most commonly diagnosed among women, 45 patients were women and 15 were men. Regarding the frequency of occurrence of a certain subtype by gender, no significant differences were observed in both IBS and PI-IBS. We noticed a higher incidence of patients residents of an urban community in both groups.The main symptoms were: abdominal pain and bowel disorders (constipation, diarrhea).There was a significant difference between the two groups regarding the onset of the symptoms. From the total of 64 patients with PI-IBS, 88.3% presented a sudden onset of symptoms (mainly abdominal pain) unlike the other group where 81% of them presented a progressive onset, with an insidious progress and sporadic exacerbation. Most patients (65.63%) presented an improvement after the treatment, 25.56% oscillating periods but with a significant decrease of intensity of symptoms, and 7.8% did not show improvement after treatment.The most common associated diseases were depression and anxiety (34.37%).

Conclusion

IBS is generally present in approximately 11% of the population, with PI-IBS patients accounting for approximately 10% of them. Female gender is more common in both IBS and PI-IBS. Patients with PI-IBS are a burden in the health system in terms of the important economic resources used for diagnosis and treatment.

Effectiveness of mesalazine to treat irritable bowel syndrome: A meta-analysis

AIM

Accumulating evidence has explored the effect of mesalazine on irritable bowel syndrome (IBS). However, these studies remain inconsistent. Thus, a meta-analysis was conducted to estimate the role of mesalazine on IBS.

METHODS

PubMed, Medline, Embase, Web of Science, and the Cochrane Library Database were searched for all relevant randomized, controlled, blinded trials on mesalazine in patients with IBS between January 1980 and October 2018. All statistical analyses were performed using Revman 5.3 software. A fixed-effects model was adopted, 95% confidence intervals for SMD was calculated. Heterogeneity was evaluated by χ test and I statistic.

RESULTS

Five studies involving 387 participants were finally included in this meta-analysis. The results showed that the SMD for clinical efficacy on abdominal pain in IBS patients treated with mesalazine in comparison to placebo was 0.19 (95% CI = -0.01 to 0.39, P = .06), which was statistically non-significant but clinically important. For beneficial effect of abdominal bloating, the SMD was 0.05 (95% CI = -0.20 to 0.30, P = .70), which was statistically non-significant. In regard to clinical efficacy on defecation frequency per day, the results revealed that the SMD was 0.29 (95% CI = -0.14 to 0.73, P = .18), which was statistically non-significant but clinically important. As for beneficial effect of general well-being, we found that the SMD was 0.41 (95% CI = -0.75 to 1.58, P = .49), which was statistically non-significant. With respect to stool consistency, the SMD was 0.01 (95% CI = -0.31 to 0.33, P = .96), which was statistically non-significant. For the effect of defecation urgency severity in IBS patients treated with mesalazine in comparison to placebo, we detected a surprising result with an SMD of 0.54 (95% CI = 0.05-1.04, P = .03), which was statistically significant. There was no significant difference between mesalazine group and placebo group on total mucosal immune cell counts of the patients with IBS with an SMD of -1.64 (95% CI = -6.17 to 2.89, P = .48) and there was also no significant difference in adverse reactions between two groups with an SMD of 1.05 (95% CI = 0.76-1.46 P = .77).

CONCLUSION

Mesalazine is not superior to placebo in relieving clinical symptoms of abdominal pain, abdominal bloating, and general well-being of IBS and has no advantage of reducing defecation frequency per day and immune cell infiltration and improving stool consistency though without adverse reactions of mesalazine compared with placebo. For defecation urgency severity, placebo is even superior to mesalazine for IBS patients. Thus, mesalazine might be a cost burden to patients without providing good effectiveness. In view of the small sample size of the current study and the differences in every experimental designs, this study has high heterogeneity and requires subsequent verification.

Painful neurotrophins and their role in visceral pain

Beyond their well-known role in embryonic development of the central and peripheral nervous system, neurotrophins, particularly nerve growth factor and brain-derived neurotrophic factor, exert an essential role in pain production and sensitization. This has mainly been studied within the framework of somatic pain, and even antibodies (tanezumab and fasinumab) have recently been developed for their use in chronic somatic painful conditions, such as osteoarthritis or low back pain. However, data suggest that neurotrophins also exert an important role in the occurrence of visceral pain and visceral sensitization. Visceral pain is a distressing symptom that prompts many consultations and is typically encountered in both 'organic' (generally inflammatory) and 'functional' (displaying no obvious structural changes in routine clinical evaluations) disorders of the gut, such as inflammatory bowel disease and irritable bowel syndrome, respectively. The present review provides a summary of neurotrophins as a molecular family and their role in pain in general and addresses recent investigations of the involvement of nerve growth factor and brain-derived neurotrophic factor in visceral pain, particularly that associated with inflammatory bowel disease and irritable bowel syndrome.

Relationship between irritable bowel syndrome and plasma and tissue ghrelin levels

BACKGROUND/AIMS

This study aimed to evaluate the relationship between irritable bowel syndrome (IBS) and plasma and tissue ghrelin levels.

MATERIALS AND METHODS

Patients who had undergone gastroscopy procedure for any reason previously were enrolled in the study. Among these, patients with IBS symptoms were evaluated according to the Roma III criteria. The healthy control group comprised patients with no IBS symptom and had undergone gastroscopy procedure for another reason. The plasma ghrelin level and tissue ghrelin level obtained by immunohistochemical examination of biopsy specimens taken from the gastric antrum and corpus were evaluated in all participants.

RESULTS

The mean age of 90 participants was 43.64}12.64 years. The median value of the plasma ghrelin level was 3.29 (1.2-12.7) in the diarrhea group (IBS-D), 1.49 (0.82-7.08) in the constipation group (IBS-C), and 1.5 (0.2-3.7) in the control group. The plasma ghrelin levels between the groups were found to be significantly higher in IBS-D than in IBS-C and the control groups (p=0.001 and p=0.001, respectively). On comparing antral mucosal gland biopsy outcomes among the groups, staining intensity score was found to be significantly high in IBS-C as compared with the control group, whereas no significant difference was observed between IBS-D and the control groups (p=0.020 and p=0.429, respectively).

CONCLUSION

The plasma ghrelin level in IBS-D and the staining intensity in the antral mucosal gland in IBS-C were found to be significantly higher. In addition, there was no difference between the groups in terms of ghrelin staining intensity in the gastric corpus.

Constipation is associated with tension type headache in women

ABSTRACT Tension-type headaches (TTH) and irritable bowel syndrome (IBS) are comorbid diseases affecting, especially, women. One of the underlying mechanisms for both is autonomic dysfunction in the brain-gut axis. We aimed to evaluate the factors accompanying TTH and their relation to functional gastrointestinal disorders. Methods: Women diagnosed with TTH were questioned about headache pattern and severity, and accompanying factors, as well as being screened for IBS according to the Rome III criteria. The participants were divided into two groups: constipation-dominant IBS (IBS-C) group and “others”, with a total of 115 individuals included in the study. Results: Of the 115 patients; 48 (41.8%) of the women had IBS-C criteria while 67 (58.2%) described mixed-type IBS or diarrhea-dominant IBS. There were no significant differences in terms of mean age (p = 0.290), body mass index (p = 0.212), visual analog scale (p = 0.965), duration of attacks (p = 0.692), and episodic/chronic type (p = 0.553). Osmophobia was seen in 43.5%; phonophobia in 68.7%, and photophobia in 47.0% of the patients, and only osmophobia was significantly associated in women in the IBS-C group (p = 0.001). Conclusion: In female patients with TTH, a higher level of constipation was detected. The relationship of these two diseases suggests that they may share common mechanisms. This is the first study showing the relationship of osmophobia with constipation.

Enhanced sensitivity to cholera toxin in female ADP-ribosylarginine hydrolase (ARH1)-deficient mice

Cholera toxin, an 84-kDa multimeric protein and a major virulence factor of Vibrio cholerae, uses the ADP-ribosyltransferase activity of its A subunit to intoxicate host cells. ADP-ribosylation is a posttranslational modification of proteins, in which the ADP-ribose moiety of NAD⁺ is transferred to an acceptor. In mammalian cells, ADP-ribosylation of acceptors appears to be reversible. ADP-ribosyltransferases (ARTs) catalyze the modification of acceptor proteins, and ADP-ribose-acceptor hydrolases (ARHs) cleave the ADP-ribose-acceptor bond. ARH1 specifically cleaves the ADP-ribose-arginine bond. We previously demonstrated a role for endogenous ARH1 in regulating the extent of cholera toxin-mediated fluid and electrolyte abnormalities in a mouse model of intoxication. Murine ARH1-knockout (KO) cells and ARH1-KO mice exhibited increased sensitivity to cholera toxin compared to their wild-type (WT) counterparts. In the current report, we examined the sensitivity to cholera toxin of male and female ARH1-KO and WT mice. Intestinal loops derived from female ARH1-KO mice when injected with cholera toxin showed increased fluid accumulation compared to male ARH1-KO mice. WT mice did not show gender differences in fluid accumulation, ADP-ribosylarginine content, and ADP-ribosyl Gαs levels. Injection of 8-Bromo-cAMP into the intestinal loops also increased fluid accumulation, however, there was no significant difference between female and male mice or in WT and KO mice. Female ARH1-KO mice showed greater amounts of ADP-ribosylated Gαs protein and increased ADP-ribosylarginine content both in whole intestine and in epithelial cells than did male ARH1-KO mice. These results demonstrate that female ARH1-KO mice are more sensitive to cholera toxin than male mice. Loss of ARH1 confers gender sensitivity to the effects of cholera toxin but not of cyclic AMP. These observations may in part explain the finding noted in some clinical reports of enhanced symptoms of cholera and/or diarrhea in women than men.

Alleviation of Irritable Bowel Syndrome-Like Symptoms and Control of Gut and Brain Responses with Oral Administration of Dolichos lablab L. in a Mouse Model

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder manifesting as unexplained abdominal pain and bowel habit changes. The pathogenesis of post-infectious IBS is associated with gut–brain axis dysfunction, including low-grade colonic inflammation and anxiety-related long-term brain changes. This study analyzed the efficacy of a standardized extract of Dolichos lablab L. extract (DL), a bean species, in an IBS mouse model resembling post-infectious, diarrhea-dominant IBS. Using a zymosan-induced animal IBS model, we found that oral administration of DL significantly attenuated zymosan-induced increases in colonic macroscopic scores and minimized weight loss without affecting food intake. In the DL-treated mice, the mast cell count and tumor necrosis factor-α level in the colon markedly decreased, similar to results in sulfasalazine-treated mice and in mice with lipopolysaccharide-stimulated bone marrow-derived mast cells. The number of visceral pain-related behaviors was much lower in the DL-treated mice. Anxiety-like behaviors significantly improved, comparable to that after treatment with amitriptyline. The c-Fos expression level in the prefrontal cortex was significantly reduced. Our data suggest that DL could be beneficial for treating IBS by acting on the gut and brain.

Functional Dyspepsia and Irritable Bowel Syndrome: Beyond Rome IV

BACKGROUND

The correct diagnosis of functional gastrointestinal disorders (FGIDs) is quite a challenge. The overlaps between syndromes can complicate the interpretation of clinical data.

SUMMARY

The incidence of functional digestive disorders and irritable bowel syndrome are still underestimated with the currently applied diagnostic tools, and the management of the seemingly elusive disease is not satisfactory. For this reason, the "Rome" criteria were created to provide a better understanding and classification of FGIDs. Key Messages: Rome diagnostic criteria and recommendations should be used in the design and performance of clinical studies in the field of functional dyspepsia and irritable bowel syndrome.

A double blind, placebo-controlled, randomized clinical trial that breast milk derived-Lactobacillus gasseri BNR17 mitigated diarrhea-dominant irritable bowel syndrome

The exact pathogenesis of diarrhea-dominant irritable bowel syndrome (IBS) is not known, but the abnormal microbiota of the gastrointestinal tract is considered to be one of the important contributing factors as in other gastrointestinal diseases such as inflammatory bowel disease, antibiotic-associated diarrhea, and colorectal cancer as well as systemic diseases. Though diverse trials of probiotics had been continued in the treatment of diarrhea-IBS, only a few proved by randomized clinical trial. To prove the efficacy of Lactobacillus gasseri BNR17 isolated from breast milk in patients with diarrhea-IBS, prospective, randomized, placebo controlled clinical trial was done including health related-quality of life analysis, colon transit time, and the changes of fecal microbiota. BNR17 significantly improved the symptoms of diarrhea compared to control group. Health related-QOL analysis showed significant improvement of abdominal pain, distension, disturbed daily life, and mean defecation frequency with BNR17. On comparative CTT before and after BNR17, 6 out of 24 subjects showed significant correction of rapid colon transit pattern, while only 2 out of 24 in placebo (p<0.01). Upon fecal microbiota analysis, BNR17 significantly increased B. fecalis, E. rectale, C. aerofaciens, F. prausnitzil and B. steroris. Conclusively, Lactobacillus gasseri BNR17 can be a potential probiotics to ameliorate diarrhea-IBS.

Inflammatory cell distribution in colon mucosa as a new tool for diagnosis of irritable bowel syndrome: A promising pilot study

BACKGROUND

Currently, there are no histological criteria to diagnose irritable bowel syndrome (IBS). Our aims were (i) to examine the distribution of inflammatory cells in the colon of healthy and IBS subjects and (ii) to find histological diagnosis criteria for IBS.

METHODS

Colonic biopsies were taken from four distinct regions of the colon from 20 controls (HC) and 11 patients with IBS (4 with constipation (IBS-C) and 7 with diarrhea (IBS-D) and embedded in paraffin. Macrophages, mast cells, eosinophils, and T lymphocytes were immunostained and positive cells counted.

KEY RESULTS

In both HC and IBS patients, global cellularity decreased from the cecum to the rectum (P < .01) which is attributed to reduced number of macrophages (P < .05) and eosinophils (P < .001) but not T cells. Mast cells were reduced in IBS (P < .05) but not in HC, particularly in IBS-D (P < .05). Results showed higher number of macrophages in the left colon of IBS subjects than HC (P < .05).

CONCLUSION & INFERENCES

Here we report a decreasing gradient of immune cells from the cecum to the rectum of the human colon. Although global cellularity cannot be used to distinguish between IBS and HC, closer analysis of macrophages and mast cells may be useful markers to confirm IBS histologically and to differentiate between IBS-C and IBS-D when clinical presentation alternates between constipation and diarrhoea. This pilot study remains to be confirmed with greater number of patients.

Transplantation of fecal microbiota from patients with irritable bowel syndrome alters gut function and behavior in recipient mice

Irritable bowel syndrome (IBS) is a common disorder characterized by altered gut function and often is accompanied by comorbid anxiety. Although changes in the gut microbiota have been documented, their relevance to the clinical expression of IBS is unknown. To evaluate a functional role for commensal gut bacteria in IBS, we colonized germ-free mice with the fecal microbiota from healthy control individuals or IBS patients with diarrhea (IBS-D), with or without anxiety, and monitored gut function and behavior in the transplanted mice. Microbiota profiles in recipient mice clustered according to the microbiota profiles of the human donors. Mice receiving the IBS-D fecal microbiota showed a taxonomically similar microbial composition to that of mice receiving the healthy control fecal microbiota. However, IBS-D mice showed different serum metabolomic profiles. Mice receiving the IBS-D fecal microbiota, but not the healthy control fecal microbiota, exhibited faster gastrointestinal transit, intestinal barrier dysfunction, innate immune activation, and anxiety-like behavior. These results indicate the potential of the gut microbiota to contribute to both intestinal and behavioral manifestations of IBS-D and suggest the potential value of microbiota-directed therapies in IBS patients.

Tryptase potentiates enteric nerve activation by histamine and serotonin: Relevance for the effects of mucosal biopsy supernatants from irritable bowel syndrome patients

BACKGROUND

We previously showed that mucosal biopsy supernatants from irritable bowel syndrome patients activated neurons despite low concentrations of tryptase, histamine, and serotonin which individually would not cause spike discharge. We studied the potentiating responses between these mediators on excitability of enteric neurons.

METHODS

Calcium-imaging was performed using the calcium-sensitive dye Fluo-4 AM in human submucous plexus preparations from 45 individuals. Histamine, serotonin, and tryptase were applied alone and in combinations to evaluate nerve activation which was assessed by analyzing increase in intracellular Ca²⁺ ([Ca²⁺ ]_i ), the proportion of responding neurons and the product of both defined as Ca-neuroindex (NI). Protease activated receptor (PAR) 2 activating peptide, PAR2 antagonist and the serine protease-inhibitor FUT-175 were used to particularly investigate the role of proteases.

KEY RESULTS

Histamine or serotonin (1 μmol/L each) evoked only few small responses (median NI [25%/75%]: 0 [0/148]; 85 [0/705] respectively). Their combined application evoked statistically similar responses (216 [21/651]). Addition of the PAR2 activator tryptase induced a significantly higher Ca-NI (1401 [867/4075]) compared to individual application of tryptase or to coapplied histamine and serotonin. This synergistic potentiation was neither mimicked by PAR2 activating peptide nor reversed by the PAR2 antagonist GB83, but abolished by FUT-175.

CONCLUSIONS & INFERENCES

We observed synergistic potentiation between histamine, serotonin, and tryptase in enteric neurons, which is mediated by proteolytic activity rather than PAR2 activation. This explained neuronal activation by a cocktail of these mediators despite their low concentrations and despite a relatively small PAR2-mediated response in human submucous neurons.

A double-blind, placebo-controlled study to assess the effect of a probiotic mixture on symptoms and inflammatory markers in women with diarrhea-predominant IBS

BACKGROUND

Micro-inflammation is considered an element in the pathogenesis of irritable bowel syndrome (IBS). High-sensitivity C reactive protein (hs-CRP) was previously shown to be higher in IBS compared to healthy controls, albeit within the normal range. Since probiotics may suppress micro-inflammation in the gut, we tested if they reduce symptoms and inflammatory markers (hs-CRP and fecal calprotectin (FC) in diarrhea-predominant IBS (IBS-D). The aim of this study was to assess the clinical and laboratory effects of BIO-25, a multispecies probiotic, in women with IBS-D.

METHODS

A double-blind, placebo-controlled study. Following a 2-week run-in, eligible women were assigned at random to a probiotic capsule or an indistinguishable placebo, twice daily for 8 weeks. IBS symptoms and stool consistency were rated daily by Visual Analogue Scales (VAS) and the Bristol Stool Scale (BSS). High-sensitivity C reactive protein was tested at baseline, 4 and 8 weeks. FC was tested at baseline and 8 weeks.

KEY RESULTS

One hundred and seventy-two IBS-D patients were recruited and 107 eligible patients were allocated to the intervention (n=54) or placebo (n=53) group. All symptoms improved in both groups with no significant difference between them in symptom improvement, hs-CRP or FC levels.

CONCLUSIONS & INFERENCES

An 8-week treatment with BIO-25 improved symptoms in women with IBS-D, but was not superior to placebo. This rigorously designed and executed study supports the findings of other studies that did not demonstrate superiority of probiotics over placebo in IBS. High quality clinical studies are necessary to examine the efficacy of other specific probiotics in IBS-D patients since data are still conflicting.

倍半萜内酯类治疗肠易激综合征的应用前景

肠易激综合征(irritable bowel syndrome, IBS)是常见的功能性肠道疾病, 以腹痛或腹部不适、排便习惯异常为特征, 其发病机制尚不明确. 依照罗马Ⅲ标准可将其分为腹泻型、便秘型、混合型和未定型4种亚型. 目前临床治疗原则主要是对症治疗, 迄今尚无特效药物能够有效治疗所有类型IBS. 倍半萜内酯类成分是众多药用植物的生物活性成分, 具有广泛生物学活性, 包括抗肿瘤、抗炎镇痛、抗菌等. 本文就倍半萜内酯类成分可改善IBS症状的相关生物学活性, 及其在IBS治疗中的应用前景进行简要综述.

Mesalazine Has No Effect on Mucosal Immune Biomarkers in Patients with Diarrhea-Dominant Irritable Bowel Syndrome Referred to Shariati Hospital: A Randomized Double-Blind, Placebo-Controlled Trial

BACKGROUND

Intestinal mast cells may cause gastrointestinal symptoms in patients with diarrhea-dominant irritable bowel syndrome (IBS). The objective of this study was to determine the effect of mesalazine on the number of lamina propria mast cells and clinical manifestations of patients with diarrhea-dominant IBS referred to Shariati Hospital affiliated to Tehran University of Medical Sciences.

METHODS

This was a randomized placebo-controlled double-blind trial conducted on 49 patients with diarrhea-dominant IBS. The patients were randomly assigned to one of the experiment or control groups. The patients in experiment group took 2400 mg mesalazine daily in three divided doses for 8 weeks and the patient in control group took placebo on the same basis. Our first targeted outcome was an assigned downturn of mast cells number to the safe colonic baseline and the next one was a marked palliation of disease symptoms. Data were analyzed conforming intention-to-treat method. We used MANCOVA test to compare our both assigned outcomes in the two groups. We also compared the data with baseline values in both groups.All statistical tests were performed at the significance level of 0.05.

RESULTS

There was no significant difference between Mesalazine and placebo groups regarding the number of mast cells (p value=0.396), abdominal pain (p value=0.054), bloating (p value=0.365), defecation urgency (p value=0.212), and defecation frequency (p value=0.702).

CONCLUSION

Mesalazine had no significant effect either on the number of mast cells or on the severity of disease symptoms. This finding seems to be inconsistent with the hypothesis indicating immune mechanisms as potential therapeutic targets in IBS. The possible difference in this effect of Mesalazine should be evaluated in further studies among populations varying in race, ethnic, and geographical characteristics.

Increased expression of nerve growth factor correlates with visceral hypersensitivity and impaired gut barrier function in diarrhoea-predominant irritable bowel syndrome: a preliminary explorative study

BACKGROUND

Neural-immune-endocrine network mechanism has attracted increased attention in diarrhoea-predominant irritable bowel syndrome (IBS-D). Pre-clinical evidence indicates that nerve growth factor (NGF) mediates visceral hypersensitivity and gut barrier dysfunction, via interactions with mast cells and sensory nerve fibres.

AIM

To explore the role of nerve growth factor, as well as mast cell-nerve growth factor-nerve interaction in IBS-D pathophysiology.

METHODS

In this cross-sectional study, IBS-D patients and healthy controls first underwent clinical and psychological assessments. Visceral sensitivity to rectal distension was tested. As gut barrier function markers, serum diamine oxidase and d-lactate were detected. Rectosigmoid biopsies were taken for the analyses of nerve growth factor expression, mast cell count and activation, and sensory nerve fibres expressing transient receptor potential vanilloid 1 and calcitonin gene-related peptide. Correlations between these parameters were examined in patients.

RESULTS

Thirty-eight IBS-D patients (28 males, 10 females; average age 30.2 years) and 20 healthy controls (12 males, 8 females; average age 26.8 years) participated in the study. The patients presented increased psychological symptoms, visceral hypersensitivity and impaired gut barrier function. NGF gene expression, mast cell count and sensory nerve fibres were significantly increased in the patients (P < 0.05). In correlation analysis, NGF expression was positively correlated with the disease severity, anxiety and serum diamine oxidase; visceral sensitivity thresholds were negatively associated with NGF expression (Bonferroni corrected P < 0.0029).

CONCLUSIONS

Elevated mucosal NGF may interact with mast cells and sensory nerve fibres, contributing to visceral hypersensitivity and impaired gut barrier function in IBS-D.

Differences of microbiota in small bowel and faeces between irritable bowel syndrome patients and healthy subjects

OBJECTIVE

Several studies suggested that colonic microbiota have impacts on irritable bowel syndrome (IBS) patients. However, the knowledge about the association of small intestine (SI) microbiota with IBS is limited. We aimed to investigate the gut microbiota composition of SI and stool in IBS patients.

MATERIALS AND METHODS

Biopsies of jejunum mucosa by balloon-assisted enteroscopy and faecal samples from 28 IBS patients and 19 healthy controls were analysed by next-generation sequencing method.

RESULTS

The three major phyla in SI microbiota of case/control groups were Proteobacteria (32.8/47.7%), Bacteroidetes (25.2/15.3%), and Firmicutes (19.8/11.2%), and those of stool were Bacteroidetes (41.3/45.8%), Firmicutes (40.7/38.2%), and Proteobacteria (15.4/7.1%). Analysis based on the family level, IBS patients had a higher proportion of Veillonellaceae (mean proportion 6.49% versus 2.68%, p = 0.046) in stool than controls. Prevotellaceae was more abundant in IBS patients than in control group (14.27% versus 6.13%, p = 0.023), while Mycobacteriaceae (0.06% versus 0.17%, p = 0.024) and Neisseriaceae (6.40% versus 8.94%, p = 0.038) was less abundant in IBS patients' jejunal mucosa than those in controls. This less abundant jejunal Neisseriaceae was associated with more severe IBS (p = 0.03). The ratio of Firmicutes to Bacteroidetes in the stool of IBS-diarrhoea type patients was approximately three-fold higher, and the ratio of Firmicutes to Actinobacter in SI of IBS-mixed type patients was about nine-fold higher than healthy subjects.

CONCLUSION

Higher abundance of colonic Veillonellaceae and SI Prevotellaceae, and lower amount of oral cavity normal flora in proximal SI were found in IBS patients. We may manipulate these bacteria in IBS patients in future studies (ClinicalTrial.gov Number NCT01679730).

The Role of Visceral Hypersensitivity in Irritable Bowel Syndrome: Pharmacological Targets and Novel Treatments

Irritable bowel syndrome (IBS) is the most common disorder referred to gastroenterologists and is characterized by altered bowel habits, abdominal pain, and bloating. Visceral hypersensitivity (VH) is a multifactorial process that may occur within the peripheral or central nervous systems and plays a principal role in the etiology of IBS symptoms. The pharmacological studies on selective drugs based on targeting specific ligands can provide novel therapies for modulation of persistent visceral hyperalgesia. The current paper reviews the cellular and molecular mechanisms underlying therapeutic targeting for providing future drugs to protect or treat visceroperception and pain sensitization in IBS patients. There are a wide range of mediators and receptors participating in visceral pain perception amongst which substances targeting afferent receptors are attractive sources of novel drugs. Novel therapeutic targets for the management of VH include compounds which alter gut-brain pathways and local neuroimmune pathways. Molecular mediators and receptors participating in pain perception and visceroperception include histamine-1 receptors, serotonin (5-hydrodytryptamine) receptors, transient receptor potential vanilloid type I, tachykinins ligands, opioid receptors, voltage-gated channels, tyrosine receptor kinase receptors, protease-activated receptors, adrenergic system ligands, cannabinoid receptors, sex hormones, and glutamate receptors which are discussed in the current review. Moreover, several plant-derived natural compounds with potential to alleviate VH in IBS have been highlighted. VH has an important role in the pathology and severity of complications in IBS. Therefore, managing VH can remarkably modulate the symptoms of IBS. More preclinical and clinical investigations are needed to provide efficacious and targeted medicines for the management of VH.

Repeated Water Avoidance Stress Alters Mucosal Mast Cell Counts, Interleukin-1β Levels with Sex Differences in the Distal Colon of Wistar Rats

Background/Aims

This study was aimed at evaluating differences in the effects of repeated water avoidance stress (rWAS) on colonic movement, mucosal mast cell counts, cytokine levels, and visceromotor response (VMR) to colorectal distension (CRD) in rats of both sexes.

Methods

Wistar rats were divided into stress and no-stress groups. Rats in the stress group were exposed to rWAS (1 hr/day) for 10 days. Mucosal mast cells were immunohistochemically stained with anti-mast cell tryptase antibody and counted. The colonic mucosal cytokine levels were measured with enzyme-linked immunosorbent assay. The VMR to CRD (visceral analgesia) was assessed by using a barostat and noninvasive manometry.

Results

The mean number of fecal pellets in the rWAS group increased significantly as compared with that in the no-stress group in both sexes. After adjustment for body weight, the female rats had a significantly higher pellet output than the male rats. The mucosal mast cell count of the female rWAS group was higher than that of the male rWAS group (13.0 ± 0.9 vs 8.8 ± 0.6; P < 0.001). The colonic mucosal interleukin-1β level was also higher only in the female rats of the rWAS group than in those of the no-stress group. On days 10 and 11, a decrease in VMR to CRD was observed at 40 and 60 mmHg in both sexes of the rWAS group, without a sex-based difference.

Conclusions

The colonic response to stress appeared to be more sensitive in the female rats than in the male rats. However, stress-induced visceral analgesia had no sex-related difference and the underlying mechanism needs to be further evaluated.

Nesfatin-1/NUCB2 in the amygdala influences visceral sensitivity via glucocorticoid and mineralocorticoid receptors in male maternal separation rats

BACKGROUND

Nesfatin-1, a recently identified satiety molecule derived from nucleobindin 2 (NUCB2), is associated with visceral hypersensitivity in rats and is expressed in the amygdala. We tested the hypothesis that nesfatin-1 expression in the amygdala is involved in the pathogenesis of irritable bowel syndrome (IBS) visceral hypersensitivity.

METHODS

An animal model of IBS-like visceral hypersensitivity was established using maternal separation (MS) during postnatal days 2-16. The role of nesfatin-1 in the amygdala on visceral sensitivity was evaluated.

KEY RESULTS

Rats subjected to MS showed a significantly increased mean abdominal withdrawal reflex (AWR) score and electromyographic (EMG) activity at 40, 60, and 80 mmHg colorectal distension. Plasma concentrations of nesfatin-1 and corticosterone were significantly higher than in non-handled (NH) rats. mRNA and protein expression of nesfatin-1/NUCB2 in the amygdala were increased in MS rats, but not in NH rats. In MS rats, AWR scores and EMG activity were significantly decreased after anti-nesfatin-1/NUCB2 injection. In normal rats, mean AWR score, EMG activity, and corticosterone expression were significantly increased after nesfatin-1 injection into the amygdala. Nesfatin-1-induced visceral hypersensitivity was abolished following application of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) antagonists.

CONCLUSIONS & INFERENCES

Elevated expression of nesfatin-1/NUCB2 in the amygdala in MS rats suggests a potential role in the pathogenesis of visceral hypersensitivity, which could potentially take place via activation of GR and MR signaling pathways.

Abdominal bloating and irritable bowel syndrome like symptoms following microinstillation inhalation exposure to chemical warfare nerve agent VX in guinea pigs

While assessing the methylphosphonothioic acid S-(2-(bis(1-methylethyl)amino)ethyl)O-ethyl ester (VX) induced respiratory toxicity and evaluating therapeutics against lung injury, we observed that the animals were experiencing abnormal swelling in the abdominal area. Nerve agent has been known to increase salivary, nasal and gastrointestinal secretion and cause diarrhea. This study was initiated to investigate the effect of VX on the gastrointestinal tract (GI) since abdominal pathology may affect breathing and contribute to the on going respiratory toxicity. The mid-abdominal diameter and the size of the lower left abdomen was measured before and after 27.3 mg/m3 VX exposure by microinstillation and at 30min intervals up to 2h post-VX exposure. Both VX and saline exposed animals exhibited a decrease in circumference of the upper abdomen, although the decrease was slightly higher in VX-exposed animals up to 1 h. The waist diameter increased slightly in VX-exposed animals from 60 to 90min post-VX exposure but was similar to saline controls. The lower left abdomen near to the cecum, 6 cm below and 2 cm to the right of the end of the sternum, showed an increase in size at 30—60 min that was significantly increased at 90—120 min post-VX exposure. In addition, VX-exposed animals showed loose fecal matter compared to controls. Necropsy at 24 h showed an increased small intestine twisting motility in VX-exposed animals. Body tissue AChE assay showed high inhibition in the esophagus and intestine in VX-exposed animals indicating that a significant amount of the agent is localized to the GI following microinstillation exposure. These results suggest that microinstillation inhalation VX exposure induces gastrointestinal disturbances similar to that of irritable bowel syndrome and bloating.

High-sensitive C-Reactive Protein as a Marker for Inflammation in Irritable Bowel Syndrome

BACKGROUND

Recent studies demonstrated low-grade inflammation in patients with irritable bowel syndrome (IBS). However, these studies have been relatively small and do not enable examination of this factor in different subtypes of IBS and the possibility of confounding effects of comorbidities that may be associated with inflammatory responses.

GOALS

To investigate the association between high-sensitive C-reactive protein (hs-CRP) and the diagnosis of IBS, IBS subtypes, symptoms' severity, and IBS-associated comorbidities.

STUDY

This cross-sectional study uses data from a large matched case-control study of IBS subjects and healthy controls (HC). hs-CRP levels were measured in all subjects. IBS diagnosis was determined by Rome III criteria, negative screening blood tests, and normal colonoscopy. Subjects were evaluated for IBS severity and associated pain and psychological comorbidities.

RESULTS

A total of 242 IBS patients and 244 HC were studied. Median hs-CRP levels in the IBS group were significantly higher than in HC (1.80; interquartile range, 0.7 to 4.04 mg/L vs. 1.20, interquartile range, 0.5 to 2.97 mg/L respectively, P<0.006). Levels were highest in IBS-D patients with greater disease severity. Hs-CRP levels mildly correlated with symptoms severity (r=0.169, P=0.009); this correlation was stronger for the IBS-D patients (r=0.27, P=0.006). IBS was a significant independent predictor (P=0.025) for higher hs-CRP levels, whereas other pain and psychological comorbidities were not.

CONCLUSIONS

Given these observations of cross-sectional differences in hs-CRP between IBS subtypes and severity, independent of pain and comorbidities, more research is needed to explore a possible role of low-grade inflammation in the pathogenesis and/or clinical presentation of IBS.

Randomized clinical study: Partially hydrolyzed guar gum (PHGG) versus placebo in the treatment of patients with irritable bowel syndrome

Background

The treatment of Irritable bowel syndrome (IBS) is still challenging. Partially hydrolyzed guar gum (PHGG) is a known prebiotic fiber. To assess the effects of PHGG on clinical symptoms of IBS patients in a prospective randomized double blind placebo-controlled study.

Methods

Suitable IBS patients were recruited into an 18-week-long study (2 weeks of run-in, 12 weeks of treatment and 4 weeks of follow-up). They were blindly randomized to receive 6 gr of PHGG or placebo. Treatment efficacy was evaluated by the Francis Severity IBS score, the IBS quality-of-life scores and scored parameters of weekly journal of symptoms. Deltas of changes between the final and baseline scores were compared between two groups.

Results

Of 121 patients who underwent randomization, 108 patients (49 in the PHGG group and 59 in the placebo group) had all the data needed for intention-to-treat analysis. A 12-week administration of PHGG led to a significant improvement of journal bloating score in the PHGG group versus placebo (−4.1±13.4 versus −1.2±11.9, P=0.03), as well as in bloating+gasses score (−4.3±10.4 versus −1.12±10.5, P = 0.035). The effect lasted for at least 4 weeks after the last PHGG administration. PHGG had no effect on other journal reported IBS symptoms or on Severity and Quality of life scores. There were no significant side effects associated with PHGG ingestion. The rate of dropouts was significantly higher among patients in the placebo group compared with the PHGG group (49.15% versus 22.45%, respectively, P = 0.01).

Conclusions

The results of this study support the administration of 6 g/day PHGG for IBS patients with bloating.

Trial registration

NCT01779765

Efficacy of Lactobacillus casei Shirota for patients with irritable bowel syndrome

BACKGROUND AND AIMS

Meta-analyses point to a modest but significant effect of probiotics on symptoms in irritable bowel syndrome (IBS). We aimed to assess the effect of the probiotic Lactobacillus casei Shirota (LcS) on symptoms and quality of life in IBS patients in a randomized, double-blind, placebo-controlled intervention study.

MATERIALS AND METHODS

IBS patients (Rome II) between 18 and 65 years of age were included. The study consisted of an 8-week intervention period in which the participants received probiotic (LcS) or placebo twice daily, followed by an 8-week follow-up period. Symptom diaries and quality of life were scored at weeks 0, 8 and 16. The primary outcome parameter was a decrease of at least 30% in a composite mean symptom score (MSS) at week 8 on the basis of an intention-to-treat analysis.

RESULTS

Thirty-nine individuals (67% women) were included in the probiotic group and 41 individuals (71% women) were included in the placebo group. After the intervention period, the mean relative improvement did not reach 30% for MSS or any individual symptom score. After follow-up (week 16), a mean improvement of at least 30% was achieved for MSS in the probiotic group, but no significant difference was found between both treatment groups (mean±SD: 34±7%; 13±8%, P=0.06).

CONCLUSION

After probiotic treatment with LcS, no improvement of 30% in MSS was observed after 8 weeks.

Rifaximin for Irritable Bowel Syndrome: A Meta-Analysis of Randomized Placebo-Controlled Trials

The current treatments for irritable bowel syndrome (IBS) are suboptimal. The findings of previous studies of rifaximin treatment for IBS may have differed due to variations in study design. Our study aimed to determine the therapeutic and adverse effects of rifaximin treatment for IBS based on a meta-analysis of published randomized controlled trials (RCTs). We searched the MEDLINE, EMBASE, EBSCO, Springer, Ovid, and Cochrane Library databases for RCTs investigating the effects of rifaximin on IBS. Data from each selected RCT was evaluated individually based on an intention-to-treat analysis, and a meta-analysis was performed in which the odds ratios (ORs) and 95% confidence intervals (CIs) of clinical outcomes and adverse events were calculated using fixed-effects models. Four eligible studies were identified. Overall relief of IBS symptoms in the rifaximin groups was greater than that in the placebo groups at the ends of both the treatment and follow-up periods (OR = 1.19; 95% CI: 1.08-1.32 and OR = 1.36; 95% CI: 1.18-1.58, respectively, P < 0.05 for both). Significant relief of abdominal distention was observed at the follow-up endpoint (OR = 1.69; 95% Cl: 1.27-2.23; P < 0.05), but not at the treatment endpoint (OR = 1.19; 95% CI: 0.96-1.49; P > 0.05). Abdominal pain (OR = 1.01; 95% CI: 0.98-1.03; P > 0.05), nausea (OR = 1.00; 95% CI: 0.98-1.02; P > 0.05), vomiting (OR: 0.99; 95% CI: 0.98-1.01; P > 0.05), and headache (OR = 1.01; 95% CI: 0.98-1.03; P > 0.05) did not differ significantly between the rifaximin and placebo groups. In the RCTs selected, our meta-analysis showed that the efficacy of rifaximin for the resolution of overall IBS symptoms was greater than that of the placebos, and that rifaximin was well-tolerated. The course of relief from abdominal distention in IBS patients treated with rifaximin may be delayed in some patients, compared with that of overall IBS symptom relief.

Food allergy in irritable bowel syndrome: The case of non-celiac wheat sensitivity

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders, having a prevalence of 12%-30% in the general population. Most patients with IBS attribute their symptoms to adverse food reactions. We review the role of diet in the pathogenesis of IBS and the importance of dietary factors in the management of these patients. The MEDLINE electronic database (1966 to Jan 2015) was searched using the following keywords: "food", "diet", "food allergy", "food hypersensitivity", "food intolerance", "IBS", "epidemiology", "pathogenesis", "pathophysiology", "diagnosis", "treatment". We found 153 eligible papers; 80 were excluded because: not written in English, exclusive biochemical and experimental research, case reports, reviews, and research otherwise not relevant to our specific interest. We selected 73 papers: 43 original papers, 26 reviews and 4 letters to the editor. These papers focused on IBS pathogenesis, the association between IBS and atopy, and between IBS and food allergy, the relationship between IBS and non-celiac wheat sensitivity, the role of diet in IBS. Pending further scientific evidence, a cautious approach is advisable but the concept of food allergy should be included as a possible cause of IBS, and a dietary approach may have a place in the routine clinical management of IBS.

Changes in Epithelial Barrier Function in Response to Parasitic Infection: Implications for IBD Pathogenesis

BACKGROUND AND AIMS

Mast cells [MCs] are implicated in epithelial barrier alterations that characterize inflammatory and functional bowel disorders. In this study, we describe mast cell proteinases [chymases and tryptases] and tight junction [TJ] proteins kinetics in a rat model of postinfectious gut dysfunction.

METHODS

Jejunal tissues of control and -infected rats were used. Inflammation-related changes in MCs and the expression of TJ-related proteins were evaluated by immunostaining and reverse transcription-quantitative polymerase chain reaction. Epithelial barrier function was assessed in vitro (Ussing chambers) and in vivo.

RESULTS

After infection, intestinal inflammation was associated with a generalized overexpression of MC chymases, peaking between Days 6 and 14. Thereafter, a mucosal MC hyperplasia and a late increase in connective tissue MC counts were observed. From Day 2 post-infection, TJ proteins occludin and claudin-3 expression was down-regulated whereas the pore-forming protein claudin-2 was overexpressed. The expression of proglucagon, precursor of the barrier-enhancing factor glucagon-like peptide-2, was reduced. These changes were associated with an increase in epithelial permeability, both in vitro and in vivo.

CONCLUSIONS

Proteinases expression and location of mucosal and connective tissue MCs indicate a time-related pattern in the maturation of intestinal MCs following infection. Altered expression of TJ-related proteins is consistent with a loss of epithelial tightness, and provides a molecular mechanism for the enhanced epithelial permeability observed in inflammatory conditions of the gut.

Visceral pain and gastrointestinal microbiome

A complex set of interactions between the microbiome, gut and brain modulate responses to visceral pain. These interactions occur at the level of the gastrointestinal mucosa, and via local neural, endocrine or immune activity; as well as by the production of factors transported through the circulatory system, like bacterial metabolites or hormones. Various psychological, infectious and other stressors can disrupt this harmonious relationship and alter both the microbiome and visceral pain responses. There are critical sensitive periods that can impact visceral pain responses in adulthood. In this review we provide a brief background of the intestinal microbiome and emerging concepts of the bidirectional interactions between the microbiome, gut and brain. We also discuss recent work in animal models, and human clinical trials using prebiotics and probiotics that alter the microbiome with resultant alterations in visceral pain responses.

Optimal management of constipation associated with irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common chronic functional disorder of the gastrointestinal tract, meanly characterized by recurrent abdominal pain or discomfort and altered bowel habit. It is a complex disorder involving biological, environmental, and psychosocial factors. The diagnosis is achieved according to the Rome III criteria provided that organic causes have been excluded. Although IBS does not constitute a life-threatening condition, it has a remarkable prevalence and profoundly reduces the quality of life with burdening socioeconomic costs. One of the principal concerns about IBS is the lack of effective therapeutic options. Up to 40% of patients are not satisfied with any available medications, especially those suffering from chronic constipation. A correct management of IBS with constipation should evolve through a global approach focused on the patient, starting with careful history taking in order to assess the presence of organic diseases that might trigger the disorder. Therefore, the second step is to examine lifestyle, dietary habits, and psychological status. On these bases, a step-up management of disease is recommended: from fiber and bulking agents, to osmotic laxative drugs, to new molecules like lubiprostone and linaclotide. Although new promising tools for relief of bowel-movement-related symptoms are being discovered, a dedicated doctor-patient relationship still seems to be the key for success.

Treatment of diarrhea-predominant irritable bowel syndrome with mesalazine and/or Saccharomyces boulardii

CONTEXT

Irritable bowel syndrome (IBS) is a functional bowel disease characterized by abdominal pain and altered intestinal habits. The pathophysiology of IBS remains unclear. Recent studies have demonstrated that some IBS patients, especially in diarrhea-predominant IBS (IBS-D), display persistent signs of minor mucosal inflammation and a modified intestinal microflora. The mesalazine has known intestinal anti-inflammatory properties. Saccharomyces boulardii is a probiotic used for a long time in treatment of diarrhea, including infectious diarrhea.

OBJECTIVE

Evaluate the effects of mesalazine alone, combined therapy of mesalazine with liophylised Saccharomyces boulardii or alone on symptoms of IBS-D patients.

METHODS

Based on Rome III criteria, 53 IBS-D patients (18 year or more) were included. To exclude organic diseases all patients underwent colonoscopy, stool culture, serum anti-endomisium antibody, lactose tolerance test and ova and parasite exam. Patients were divided in three groups: mesalazine group (MG) - 20 patients received mesalazine 800 mg t.i.d. for 30 days; mesalazine and Saccharomyces boulardii group (MSbG) - 21 patients received mesalazine 800 mg t.i.d. and Saccharomyces boulardii 200 mg t.i.d. for 30 days and; Saccharomyces boulardii group (SbG) - 12 patients received Sb 200 mg t.i.d. for 30 days. Drugs that might have any effect on intestinal motility or secretion were not allowed. Symptom evaluations at baseline and after treatment were performed by means of a 4-point likert scale including: stool frequency, stool form and consistency (Bristol scale), abdominal pain and distension. Paired t test and Kruskal-Wallis test were used for statistical analyses.

RESULTS

Compared to baseline, there were statistically significant reduction of symptom score after 30 th day therapy in all three groups: MG (P<0.0001); MSbG (P<0.0001) and in SbG (P = 0.003). There were statistically significant differences in the symptom score at 30 th day therapy of the MG, MSbG and SbG groups (P = 0.03). There were no statistical differences between MSbG and MG symptom score at 30th day therapy (P = 0.9).

CONCLUSIONS

The use of mesalazine alone, Saccharomyces boulardii alone or combined treatment with mesalasine and Saccaromyces boulardii improved IBS-D symptoms. The improvement of the symptom score was greater with mesalazine alone or combined with Sb as compared with Sb treatment alone. These preliminary results suggest that mezalazine may be useful in treatment of IBS-d patients, and warrant further larger studies.

Clinical expression of lymphocytic duodenosis in "mild enteropathy" celiac disease and in functional gastrointestinal syndromes

OBJECTIVE

Abnormally high number of duodenal intraepithelial lymphocytes is frequently found in many conditions including mild enteropathy celiac disease (CD) and functional gastrointestinal syndromes, but is unclear whether lymphocytosis affects the clinical phenotype particularly in functional syndromes.

MATERIALS AND METHODS

We compared clinical characteristics of celiac patients with lymphocytic duodenosis and normal villous structure with those of patients with functional gastrointestinal syndromes with and without lymphocytic duodenosis. We retrospectively identified 3 cohorts among patients referred for suspected CD: (1) "CoelD", 135 patients (age 36 ± 14 years) with mild enteropathy CD; (2) "LymD", 245 patients (38 ± 12 years) with functional gastrointestinal syndromes and lymphocytic duodenosis; and (3) "NorD", 147 patients (37 ± 15 years) with functional syndromes and normal duodenal histology.

RESULTS

Prevalence of gastrointestinal symptoms was similar in the three cohorts, but prevalence of extra-intestinal manifestations (42% vs. 27% vs. 18%, p < 0.003) and of associated diseases (35% vs. 15% vs. 14%, p < 0.0001) was higher in "CoelD" than in "LymD" and "NorD", respectively. Prevalence of Helicobacter pylori infection was similar in the three cohorts. The proportion of patients with final diagnosis of irritable bowel syndrome-diarrhea (38% vs. 37%), dyspepsia (31% vs. 27%), functional pain (14% vs. 19%), and functional diarrhoea (14% vs. 11%) was virtually the same in the cohorts with (LymD) and without (NorD) lymphocytic duodenosis.

CONCLUSIONS

Lymphocytic duodenosis has different clinical presentation in patients with mild enteropathy CD than those with functional gastrointestinal syndromes, and is not specific for any particular functional syndrome.

Mucosal layers and related nerve fibres in non-chagasic and chagasic human colon--a quantitative immunohistochemical study

Chagasic megacolon is accompanied by extensive myenteric and, simultaneously, moderate submucosal neuron loss. Here, we examined changes of the innervation pattern of the lamina propria (LP) and muscularis mucosae (MM). Two alternating sets of cryosections were taken from seven non-chagasic colonic and seven chagasic megacolonic specimens (the latter included both the dilated megacolonic and the non-dilated transitional oral and anal zones) and were immunohistochemically triple-stained for smooth-muscle actin (SMA), synaptophysin (SYN) and glial acid protein S100 and, alternatively, for SMA, vasoactive intestinal peptide (VIP) and somatostatin (SOM). Subsequent image analysis and statistical evaluation of nervous tissue profile areas revealed that, in LP, the most extreme differences (i.e. increase in thickness or decrease in nerve, glia and muscle tissue profile area, respectively) compared with control values occurred in the dilated megacolonic zone itself. In contrast, the most extreme differences in the MM were in the anal-to-megacolonic zone (except the profile area of muscle tissue, which was lowest in the megacolonic zone). This parallels our previous results in the external muscle coat. A partial and selective survival of VIP-immunoreactive in contrast to SOM-immunoreactive nerve fibres was observed in both mucosal layers investigated. Thus, VIPergic nerve elements might be crucial for the maintenance of the mucosal barrier. The differential changes of neural tissue parameters in LP and MM might reflect a multifactorial rather than a pure neurogenic development of megacolon in chronic Chagas' disease.

Intestinal allergic inflammation in birch pollen allergic patients in relation to pollen season, IgE sensitization profile and gastrointestinal symptoms

BACKGROUND

Birch pollen allergic patients frequently experience gastrointestinal upset accompanied by a local allergic inflammation in the small intestine especially during the pollen season. However, it is not known if the GI pathology is connected to the subjective symptoms of the patient. The objective of this study was to evaluate the immune pathology of the duodenal mucosa and the serum IgE antibody profiles in birch pollen allergic patients in relation to their gastrointestinal symptoms, during and outside the birch pollen season.

METHODS

Thirty-two patients with birch pollen allergy and sixteen healthy controls were enrolled in the study. Twenty allergic patients had gastrointestinal symptoms and twelve did not. All participants underwent an allergy investigation and gastroscopy with duodenal biopsy. The duodenal biopsies were retrieved during the pollen season (May-June) and off-season (November-March). The biopsies were immunostained for mast cells (IgE and tryptase), eosinophils, T cells (CD3), and dendritic cells (CD11c). Pollen-specific IgE antibodies were determined by ImmunoCAP and component microarray (ISAC).

RESULTS

Patients in both pollen allergic groups showed similar degree of intestinal allergic inflammation during the pollen season regardless of gastrointestinal symptoms. The eosinophils, mast cells and dendritic cells were increased in the mucosa. Patients with gastrointestinal symptoms had significantly elevated IgE antibodies to birch (rBet v 1), hazelnut (rCor a 1), and apple (rMal d1) during the pollen season.

CONCLUSIONS

Patients allergic to birch pollen have clear signs of an ongoing allergic inflammation in their intestinal mucosa, which is aggravated during the pollen season. The magnitude of the allergic intestinal inflammation is not associated with subjective gastrointestinal symptoms of the individual patient.

Antioxidant activity of inulin and its role in the prevention of human colonic muscle cell impairment induced by lipopolysaccharide mucosal exposure

BACKGROUND

Fructans, such as inulin, are dietary fibers which stimulate gastro-intestinal (GI) function acting as prebiotics. Lipopolysaccharide (LPS) impairs GI motility, through production of reactive oxygen species. The antioxidant activity of various fructans was tested and the protective effect of inulin on colonic smooth muscle cell (SMC) impairment, induced by exposure of human mucosa to LPS, was assessed in an ex vivo experimental model.

METHODS

The antioxidant capacity of fructans was measured in an in vitro system that simulates cooking and digestion processes. Human colonic mucosa and submucosa, obtained from disease-free margins of resected segments for cancer, were sealed between two chambers, with the mucosal side facing upwards with Krebs solution with or without purified LPS from a pathogenic strain of Escherichia coli (O111:B4) and inulin (Frutafit IQ), and the submucosal side facing downwards into Krebs solution. The solutions on the submucosal side were collected following mucosal exposure to Krebs in the absence (N-undernatant) or presence of LPS (LPS-undernatant) or LPS+inulin (LPS+INU-undernatant). Undernatants were tested for their antioxidant activity and the effects on SMCs contractility. Inulin protective effects on mucosa and submucosa layers were assessed measuring the protein oxidation level in the experimental conditions analyzed.

RESULTS

Antioxidant activity of inulin, which was significantly higher compared to simple sugars, remained unaltered despite cooking and digestion processes. Inulin protected the mucosal and submucosal layers against protein oxidation. Following exposure to LPS-undernatant, a significant decrease in maximal acetylcholine (Ach)-induced contraction was observed when compared to the contraction induced in cells incubated with the N-undernatant (4±1% vs 25±5% respectively, P<0.005) and this effect was completely prevented by pre-incubation of LPS with Inulin (35±5%).

CONCLUSIONS

Inulin protects the human colon mucosa from LPS-induced damage and this effect appears to be related to the protective effect of inulin against LPS-induced oxidative stress.

Development of determination of four analytes of Zhi-Shao-San decoction using LC-MS/MS and its application to comparative pharmacokinetics in normal and irritable bowel syndrome rat plasma

Zhi-Shao-San (ZSS), a traditional Chinese medicinal prescription, has been clinically used for the treatment of irritable bowel syndrome (IBS) for centuries. A comparative study was designed and conducted to compare the pharmacokinetic differences between paeoniflorin naringin, hesperidin and neohesperidin after oral administration of ZSS decoction to normal rats and IBS rats induced by acetic acid and restraint stress. Further, an efficient, sensitive and selective liquid chromatography/tandem mass spectrometry for the simultaneous determination of four analytes of ZSS decoction in rat plasma was developed and validated. The validated method was successfully applied to comparison of pharmacokinetic profiles of analytes in rat plasma. The results showed that the absorptions of naringin, hesperidin and neohesperidin in IBS group were all significantly higher than those in normal group and no obvious difference was seen for paeoniflorin between the two groups, which is helpful for improving clinical therapeutic efficacy and further pharmacological studies of ZSS.

Chemotactic chemokines are important in the pathogenesis of irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most frequently diagnosed disorders, affecting about 20% of the general population in Western countries. This syndrome poses an enormous socio-economic burden, impairs the quality of life substantially, and increases healthcare costs. IBS can be classified as either idiopathic (ID-IBS) with unknown etiology or post-infectious (PI-IBS), which develops after a bout of acute diarrhea or gastroenteritis. Little is known about the immunopathogenesis of these two forms of IBS. We evaluated various biomarkers in clinical samples of ID-IBS and PI-IBS patients with the goal to test the hypothesis that the immunologic presentations of these forms of IBS are similar, despite their apparent different etiologic origins. Sera and stool samples from PI-IBS, ID-IBS, and healthy volunteers were analyzed for relative amounts of 36 different biomarkers using the Proteome Profiler Human Cytokine Array Panel A Kit and quantitative ELISA. Our results demonstrated significantly high levels of chemotactic chemokines monocytes chemotactic protein-1 (CCL2) [p-value  = 0.003], macrophage inflammatory protein-1β (CCL4) [p-value  = 0.010], and CXCL16 (p-value 0.001) in the sera and stools of both ID-IBS and PI-IBS patients. Furthermore, pro-inflammatory cytokines (IFN-γ, IL-1β, and TNF-α) were significantly higher in IBS patients. Anti-inflammatory cytokines (IL-10, IL-4, and IL-13) were variable except IL-10, which was significantly higher in the healthy volunteers than the IBS patients. Remarkably, the amounts and expression pattern of these biomarkers were not significantly different between ID-IBS and PI-IBS. Thus, ID-IBS and PI-IBS present similar immunologic and clinical phenotypes, in spite of their different etiologic origins.

Irritable bowel syndrome: Emerging paradigm in pathophysiology

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders, characterized by abdominal pain, bloating, and changes in bowel habits. These symptoms cannot be explained by structural abnormalities and there is no specific laboratory test or biomarker for IBS. Therefore, IBS is classified as a functional disorder with diagnosis dependent on the history taking about manifested symptoms and careful physical examination. Although a great deal of research has been carried out in this area, the pathophysiology of IBS is complex and not completely understood. Multiple factors are thought to contribute to the symptoms in IBS patients; altered gastrointestinal motility, visceral hypersensitivity, and the brain-gut interaction are important classical concepts in IBS pathophysiology. New areas of research in this arena include inflammation, postinfectious low-grade inflammation, genetic and immunologic factors, an altered microbiota, dietary factors, and enteroendocrine cells. These emerging studies have not shown consistent results, provoking controversy in the IBS field. However, certain lines of evidence suggest that these mechanisms are important at least a subset of IBS patients, confirming that IBS symptoms cannot be explained by a single etiological mechanism. Therefore, it is important to keep in mind that IBS requires a more holistic approach to determining effective treatment and understanding the underlying mechanisms.

Chronic functional bowel syndrome enhances gut-brain axis dysfunction, neuroinflammation, cognitive impairment, and vulnerability to dementia

The irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disorder world wide that lasts for decades. The human gut harbors a diverse population of microbial organisms which is symbiotic and important for well being. However, studies on conventional, germ-free, and obese animals have shown that alteration in normal commensal gut microbiota and an increase in pathogenic microbiota-termed "dysbiosis", impact gut function, homeostasis, and health. Diarrhea, constipation, visceral hypersensitivity, and abdominal pain arise in IBS from the gut-induced dysfunctional metabolic, immune, and neuro-immune communication. Dysbiosis in IBS is associated with gut inflammation. Gut-related inflammation is pivotal in promoting endotoxemia, systemic inflammation, and neuroinflammation. A significant proportion of IBS patients chronically consume alcohol, non-steroidal anti-inflammatories, and fatty diet; they may also suffer from co-morbid respiratory, neuromuscular, psychological, sleep, and neurological disorders. The above pathophysiological substrate is underpinned by dysbiosis, and dysfunctional bidirectional "Gut-Brain Axis" pathways. Pathogenic gut microbiota-related systemic inflammation (due to increased lipopolysaccharide and pro-inflammatory cytokines, and barrier dysfunction), may trigger neuroinflammation enhancing dysfunctional brain regions including hippocampus and cerebellum. These as well as dysfunctional vago-vagal gut-brain axis may promote cognitive impairment. Indeed, inflammation is characteristic of a broad spectrum of neurodegenerative diseases that manifest demntia. It is argued that an awareness of pathophysiological impact of IBS and implementation of appropriate therapeutic measures may prevent cognitive impairment and minimize vulnerability to dementia.

Efficacy and Safety of Tiropramide in the Treatment of Patients With Irritable Bowel Syndrome: A Multicenter, Randomized, Double-blind, Non-inferiority Trial, Compared With Octylonium

Background/Aims

Antispasmodics such as octylonium are widely used to manage irritable bowel syndrome (IBS) symptoms. However, the efficacy and safety of another antispasmodic, tiropramide, remain uncertain. We aimed to evaluate the efficacy and safety of tiropramide compared with octylonium in patients with IBS.

Methods

In this multicenter, randomized, non-inferiority trial, 287 patients with IBS (143 receiving tiropramide and 144 octylonium) were randomly allocated to either tiropramide 100 mg or octylonium 20 mg t.i.d (means 3 times a day) for 4 weeks. Primary endpoint was the mean change of abdominal pain from baseline assessed by visual analogue scales (VAS) score after 4 weeks of treatment. Secondary endpoints were the changes in abdominal pain from baseline at week 2 and in abdominal discomfort at weeks 2 and 4, using VAS scores, patient-reported symptom improvement including stool frequency and consistency, using symptom diaries, IBS-quality of life (IBS-QoL), and depression and anxiety, at week 4.

Results

The VAS scores of abdominal pain at week 4, were significantly decreased in both tiropramide and octylonium groups, but the change from baseline did not differ between the 2 groups (difference,-0.26 mm; 95% CI,-4.33-3.82; P = 0.901). Abdominal pain and discomfort assessed using VAS scores, diaries, and IBS-QoL were also improved by both treatments, and the changes from baseline did not differ. The incidence of adverse events was similar in the 2 groups, and no severe adverse events involving either drug were observed.

Conclusions

Tiropramide is as effective as octylonium in managing abdominal pain in IBS, with a similar safety profile.

Human colonic myogenic dysfunction induced by mucosal lipopolysaccharide translocation and oxidative stress

BACKGROUND

Impairment of gastrointestinal motility is frequently observed in patients with severe infection.

AIM

To assess whether exposure of human colonic mucosa to pathogenic lipopolysaccharide affects smooth muscle contractility.

METHODS

Human colonic mucosa and submucosa were sealed between two chambers, with the luminal side facing upwards and covered with Krebs solution, with or without lipopolysaccharide from a pathogenic strain of Escherichia coli (O111:B4; 1,000 ng/mL), and with the submucosal side facing downwards into Krebs. The solution on the submucosal side was collected following 30-min mucosal exposure to Krebs without (N-undernatant) or with lipopolysaccharide (lipopolysaccharide undernatant). Undernatants were tested for lipopolysaccharide and hydrogen peroxide levels and for their effects on smooth muscle cells in the presence of catalase, indomethacin or MG132.

RESULTS

Smooth muscle cells incubated with N-undernatant had a maximal contraction of 32 ± 5% that was reduced by 62.9 ± 12% when exposed to lipopolysaccharide undernatant. Inhibition of contraction was reversed by catalase, indomethacin and MG132. Lipopolysaccharide levels were higher in the lipopolysaccharide undernatant (2.7 ± 0.7 ng/mL) than in N-undernatant (0.45 ± 0.06 ng/mL) as well as hydrogen peroxide levels (133.75 ± 15.9 vs 82 ± 7.5 nM respectively).

CONCLUSIONS

Acute exposure of colonic mucosa to pathogenic lipopolysaccharide impairs muscle cell contractility owing to both lipopolysaccharide mucosal translocation and production of free radicals.

Irritable bowel syndrome-type symptoms in female patients with mild systemic lupus erythematosus: frequency, related factors and quality of life

BACKGROUND

Irritable bowel syndrome (IBS) impairs quality of life (HRQOL), as does systemic lupus erythematosus (SLE). Both are more common in women and are associated with fibromyalgia (FM). However, the relationship between IBS and SLE and its impact on HRQOL has not been explored. Therefore, we aimed to study the frequency and features likely to influence the presence of IBS-type symptoms in SLE and their impact on HRQOL.

METHODS

Female patients with SLE were studied. The presence of IBS-type symptoms and bowel habit subtype were established by Rome III criteria and HRQOL was assessed using the SF-36. Fibromyalgia and depression were assessed using the American College of Rheumatology criteria and CES-D scale, respectively.

KEY RESULTS

A total of 105 consecutive patients (43.62 ± 11.34 years old) were included; 48.6% had IBS-type symptoms (SLE+IBS) and were classified as IBS-C: 23.5%, IBS-D: 37.3%, and IBS-M: 39.2%. In addition, 23.8% had FM. SLE+IBS vs Non-IBS SLE patients had higher SLE activity scores (2.55 ± 1.65 vs 1.74 ± 2.19; p = 0.03), were more likely to have FM (33.0% vs 14.8%; p = 0.02) and depression (41.1% vs 25.9%, p = 0.04). Logistic multivariate analysis showed that IBS-type symptoms were associated with FM (OR = 2.85, 95% CI: 1.11-7.43) and depression (OR = 1.07, 95% CI: 1.02-1.13). Finally, SLE+IBS vs Non-IBS SLE patients had lower SF-36 scores (49.65 ± 18.57 vs 62.67 ± 18.14; p = 0.02).

CONCLUSIONS & INFERENCES

IBS-type symptoms are highly prevalent among women with SLE and are associated with FM and depression. SLE+IBS patients had worse HRQOL vs Non-IBS SLE, independently of FM status. We suggest that treating IBS symptoms may improve HRQOL in women with SLE.