The overlap between irritable bowel syndrome and organic gastrointestinal diseases

Tong-Xie-Yao-Fang strengthens intestinal feedback control of bile acid synthesis to ameliorate irritable bowel syndrome by enhancing bile salt hydrolase-expressing microbiota

ETHNOPHARMACOLOGICAL RELEVANCE

A herbal formula Tong-Xie-Yao-Fang (TXYF) is traditionally used to treat irritable bowel syndrome (IBS), modern pharmacological evidence supports that the formula efficacy is associated with altered gut microbiota. Yet, the mechanistic role of gut microbiota in the therapy of TXYF remains unclear. We previously clarified that gut microbiota-dysregulated bile acid (BA) metabolism contribute to the pathogenesis of IBS, deriving a hypothesis that microbiota-BA metabolic axis might be a potential target of TXYF.

AIM OF THE STUDY

We aim to investigate a new gut microbiota-mediated mechanism underlying anti-IBS efficacy of TXYF.

MATERIALS AND METHODS

We established an IBS rat model with a combination of stressors, compared the herbal efficacy in models undergone gut bacterial manipulations, also examined BA metabolism-related microbiota, metabolites, genes and proteins by 16S rRNA gene sequencing, targeted metabolomics, qPCR and multiplex immunofluorescence staining.

RESULTS

We observed that TXYF attenuated visceral hyperalgesia and diarrhea in IBS rats but not in those underwent gut bacteria depletion. Transferring gut microbiota from TXYF-treated donors also decreased visceral sensitivity and slightly relief diarrhea-like behaviors in IBS recipient rats. Fecal 16S rRNA gene sequencing revealed that TXYF modulated microbial β-diversity and taxonomic structure of IBS rats, with a significant increase in relative abundance of bile salt hydrolase (BSH)-expressing Bacteroidaceae. qPCR and culturing data validated that TXYF had a promotive effect on the growth and BSH activity of Bacteroides species. TXYF-reshaped microbiota upregulated the expression of intestinal Fgf15, a feedback signal to control BA synthesis in the liver. As a result, the BA synthetic and excretory levels in IBS rats were decreased by TXYF, so as that colonic BA membrane receptor Tgr5 sensing and its mediated Calcitonin gene-related peptide (Cgrp)-positive neuronal response were attenuated.

CONCLUSION

This study poses a new microbiota-driven therapeutic action for TXYF, highlighting the potential of developing new anti-IBS strategies from the herbal formula targeting BSH-expressing gut bacteria.

Lactiplantibacillus plantarum Regulates Intestinal Physiology and Enteric Neurons in IBS through Microbial Tryptophan Metabolites

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder characterized by visceral pain and gut dysmotility. However, the specific mechanisms by which Lactobacillus strains relieve IBS remain unclear. Here, we screened Lactobacillus strains from traditional Chinese fermented foods with potential IBS-alleviating properties through in vitro and in vivo experiments. We demonstrated that Lactiplantibacillus plantarum D266 (Lp D266) administration effectively modulates intestinal peristalsis, enteric neurons, visceral hypersensitivity, colonic inflammation, gut barrier function, and mast cell activation. Additionally, Lp D266 shapes gut microbiota and enhances tryptophan (Trp) metabolism, thus activating the aryl hydrocarbon receptor (AhR) and subsequently enhancing IL-22 production to maintain gut homeostasis. Mechanistically, Lp D266 potentially modulates colonic physiology and enteric neurons by microbial tryptophan metabolites. Further, our study indicates that combining Lp D266 with Trp synergistically ameliorates IBS symptoms. Together, our experiments identify the therapeutic efficacy of tryptophan-catabolizing Lp D266 in regulating gut physiology and enteric neurons, providing new insights into the development of probiotic-mediated nutritional intervention for IBS management.

Managing patients' reports of abdominal pain and irritable bowel syndrome-like symptoms during quiescent inflammatory bowel disease: a role for shared sensemaking

Background

Patients with inflammatory bowel disease (IBD) are often faced with distressing and confusing abdominal pain during remission. Some people respond adversely to healthcare professionals' (HCPs) suggestions that this pain and related symptoms are due to secondary irritable bowel syndrome (IBS). Exploring how HCPs view, manage, and explain pain during quiescent disease may provide insights into how communication can be improved to increase understanding and mitigate negative responses.

Methods

In-depth semi-structured interviews were conducted with 12 IBD-nurses (n = 4) and gastroenterologists (n = 8) working in the United Kingdom or the Netherlands. Reflexive thematic analysis was used to analyse interviews.

Results

Findings suggest that HCPs pay relatively little attention to pain when there is no underlying pathology and prefer to concentrate on objectifiable causes of symptoms and treating disease activity (Theme 1: Focus on disease activity, not pain and associated symptoms). Explanations of abdominal pain and IBS-like symptoms during remission were not standardised (Theme 2: Idiosyncratic and uncertain explanations for pain during remission). Processes of shared decision-making were outlined and shared sensemaking was reported as a strategy to enhance acceptance of IBS explanations (Theme 3: Shared decision making versus shared sensemaking).

Conclusion

Future work should focus on establishing how pain during remission may be best defined, when to diagnose IBS in the context of IBD, and how to explain both to patients. The formulation of standardised explanations is recommended as they might help HCPs to adopt practices of shared sensemaking and shared decision-making. Explanations should be adaptable to specific symptom presentations and different health literacy levels.

Association Between Celiac Disease and Irritable Bowel Syndrome: A Nationwide Cohort Study

BACKGROUND & AIMS

The aim of this study was to determine the risk of irritable bowel syndrome (IBS) diagnosis in patients with celiac disease (CD) compared with general population comparators.

METHODS

Using Swedish histopathology and register-based data, we identified 27,262 patients with CD diagnosed in 2002-2017 and 132,922 age- and sex-matched general population comparators. Diagnoses of IBS were obtained from nationwide inpatient and non-primary outpatient records. Cox regression estimated hazard ratios (aHRs) for IBS adjusted for education level and Charlson Comorbidity Index. To reduce potential surveillance bias our analyses considered incident IBS diagnosis ≥1 year after CD diagnosis. Using conditional logistic regression, secondary analyses were calculated to estimate odds ratios (ORs) for IBS diagnosis ≥1 year before CD diagnosis.

RESULTS

During an average of 11.1 years of follow-up, 732 celiac patients (2.7%) were diagnosed with IBS vs 1131 matched general population comparators (0.9%). Overall (≥1-year of follow-up), the aHR for IBS was 3.11 (95% confidence interval [CI], 2.83-3.42), with aHR of 2.00 (95% CI, 1.63-2.45) after ≥10 years of follow-up. Compared with siblings (n = 32,010), celiac patients (n = 19,211) had ≥2-fold risk of later IBS (aHR, 2.42; 95% CI, 2.08-2.82). Compared with celiac patients with mucosal healing, those with persistent villus atrophy on follow-up biopsy were less likely to be diagnosed with IBS (aHR, 0.66; 95% CI, 0.46-0.95). CD was also associated with having an earlier IBS diagnosis (OR, 3.62; 95% CI, 3.03-4.34).

CONCLUSIONS

In patients with CD, the risk of IBS is increased long before and after diagnosis. Clinicians should be aware of these long-term associations and their implications on patient management.

Fecal and Serum Granulocyte Protein Levels in Inflammatory Bowel Disease and Irritable Bowel Syndrome and Their Relation to Disease Activity

INTRODUCTION

Neutrophilic calprotectin (CP) and myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL), and eosinophil-derived neurotoxin (EDN) are suggested proxy markers for gut inflammation. However, there are insufficient supporting data for MPO, NGAL, and EDN.

METHODS

In a cross-sectional investigation including adult patients, we studied the ability of CP, MPO, NGAL, and EDN, measured in fecal and serum samples, to differentiate between inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), and to predict disease activity.

RESULTS

Fifty-nine patients had ulcerative colitis (UC), 38 had Crohn's disease, and 100 patients had IBS. The protein concentrations were higher in patients with IBD in the fecal samples ( P < 0.001) and the serum samples ( P < 0.01), and they correlated weakly (r s ≤0.38) between the sample sources. Fecal EDN was higher in patients with Crohn's disease compared with UC (1.79 vs 0.50 mg/kg, P = 0.016). The neutrophilic proteins were superior to EDN in the fecal samples for differentiating between patients with IBD and IBS. Fecal MPO (cutoff: 0.86 mg/kg) had the highest sensitivity (74.7%) and specificity (84.6%). Combining fecal CP and MPO increased the sensitivity to 82.3% (specificity: 73.6%). NGAL (cutoff: 196.9 μg/L) showed the best discriminating performance in serum (sensitivity: 62.9%; specificity: 68.0%). Serum NGAL (cutoff: 272.4 μg/L) predicted active disease in UC (Partial Mayo Score ≥2) with a sensitivity and specificity of 57.1% and 83.3%, respectively.

DISCUSSION

Fecal MPO and serum NGAL are promising novel biomarkers, in addition to fecal CP, for differentiating between IBD and IBS. Serum NGAL may also predict disease activity in patients with UC.

Engagement in GI Behavioral Health Is Associated with Reduced Portal Messages, Phone Calls, and ED Visits

BACKGROUND AND AIMS

Chronic digestive disorders are associated with increased costs for healthcare systems and often require provision of both urgent care and non-face-to-face (non-F2F) care, such as responding to patient messages. Numerous benefits of integrated gastroenterology (GI) behavioral health have been identified; however, it is unclear if integrated care impacts healthcare utilization, including urgent care and non-F2F contact. We sought to investigate the association between patient engagement with GI behavioral health and healthcare utilization.

METHODS

We performed a retrospective chart review study of adult patients who were referred for and completed at least one behavioral health appointment between January 1, 2019 and December 21, 2021 in the Gastroenterology and Hepatology department of a large academic medical center. Data on electronic medical record (EMR) messages, phone calls, and Emergency Department utilization were collected 6 months before and 9 months after patient engagement with GI behavioral health.

RESULTS

466 adult patients completed at least one behavioral health visit from 2019 to 2021. Overall, messages, phone calls, and ED visits all decreased significantly from the 6 months before behavioral health treatment to 6 months after (all P values < 0.001).

CONCLUSION

Engagement with integrated GI behavioral health is associated with reduced non-F2F care and emergency department utilization in patients with chronic digestive disorders. Increasing access to GI behavioral health may result in reduced provider workload and healthcare system costs.

Electroacupuncture Improving Intestinal Barrier Function in Rats with Irritable Bowel Syndrome Through Regulating Aquaporins

BACKGROUND

Intestinal mucosal barrier dysfunction plays a crucial role in the pathogenesis of irritable bowel syndrome with diarrhea (IBS-D). In order to explore the mechanism of electroacupuncture (EA) treatment on intestinal mucosal barrier, this study observed the effect of EA on aquaporins (AQPs), tight junctions (TJs), NF-κB pathway and the gut microbiota in IBS-D rats.

METHODS

The IBS-D model was established by acetic acid enema combined with chronic restraint method. The effects of EA on the treatment of IBS-D were examined by the abdominal withdrawal reflex score, Bristol's fecal character score, fecal water content, small intestine propulsion rate and HE staining. AQPs, TJs and inflammation-related molecular mechanisms were explored. The fecal samples were applied for 16S rRNA sequencing to assess the effect of EA intervention to the intestinal bacterial abundance.

RESULTS

EA reduced intestinal sensitization, restored intestinal motility and improved inflammatory cell infiltration. Furthermore, EA improved intestinal inflammation and flora environment significantly, inhibited NF-κB signaling and inflammatory factors (IL-1β and TNF-α). It can also increase the gene and protein expression of AQPs (AQP1, AQP3, and AQP8) and the gene levels of TJs (ZO-1 and Occludin).

CONCLUSION

EA has an inhibitory effect on the NF-κB signaling pathway, and regulates the proteins of AQP1, AQP3, AQP8, and TJs to restore the balance of water metabolism and intestinal permeability in IBS-D, which also restored the function of the intestinal mucosa by regulating the intestinal flora.

Protease-Induced Excitation of Dorsal Root Ganglion Neurons in Response to Acute Perturbation of the Gut Microbiota Is Associated With Visceral and Somatic Hypersensitivity

BACKGROUND & AIMS

Abdominal pain is a major symptom of diseases that are associated with microbial dysbiosis, including irritable bowel syndrome and inflammatory bowel disease. Germ-free mice are more prone to abdominal pain than conventionally housed mice, and reconstitution of the microbiota in germ-free mice reduces abdominal pain sensitivity. However, the mechanisms underlying microbial modulation of pain remain elusive. We hypothesized that disruption of the intestinal microbiota modulates the excitability of peripheral nociceptive neurons.

METHODS

In vivo and in vitro assays of visceral sensation were performed on mice treated with the nonabsorbable antibiotic vancomycin (50 μg/mL in drinking water) for 7 days and water-treated control mice. Bacterial dysbiosis was verified by 16s rRNA analysis of stool microbial composition.

RESULTS

Treatment of mice with vancomycin led to an increased sensitivity to colonic distension in vivo and in vitro and hyperexcitability of dorsal root ganglion (DRG) neurons in vitro, compared with controls. Interestingly, hyperexcitability of DRG neurons was not restricted to those that innervated the gut, suggesting a widespread effect of gut dysbiosis on peripheral pain circuits. Consistent with this, mice treated with vancomycin were more sensitive than control mice to thermal stimuli applied to hind paws. Incubation of DRG neurons from naive mice in serum from vancomycin-treated mice increased DRG neuron excitability, suggesting that microbial dysbiosis alters circulating mediators that influence nociception. The cysteine protease inhibitor E64 (30 nmol/L) and the protease-activated receptor 2 (PAR-2) antagonist GB-83 (10 μmol/L) each blocked the increase in DRG neuron excitability in response to serum from vancomycin-treated mice, as did the knockout of PAR-2 in NaV1.8-expressing neurons. Stool supernatant, but not colonic supernatant, from mice treated with vancomycin increased DRG neuron excitability via cysteine protease activation of PAR-2.

CONCLUSIONS

Together, these data suggest that gut microbial dysbiosis alters pain sensitivity and identify cysteine proteases as a potential mediator of this effect.

Sieving out non-celiac gluten sensitivity amongst patients with irritable bowel syndrome

OBJECTIVES

It is challenging to make diagnosis of non-celiac gluten sensitivity/non-celiac wheat sensitivity (NCGS/NCWS) in clinical practice, since there is no biomarker and diagnosis is based on response to gluten-free-diet (GFD). We used anti-gliadin antibody (AGA) for screening patients with IBS for gluten-sensitivity.

METHODS

492 Adult-patients with IBS underwent screening for celiac disease and gluten-sensitivity using IgA anti-tissue transglutaminase antibody and IgA-AGA and IgG-AGA, respectively. Patients with positive AGA (IgA and/or IgG) were invited to follow GFD, those willing were put on GFD for 6-weeks. Responsive patients were given gluten re-challenge. Diagnosis of NCGS was confirmed if they had recurrence of symptoms.

RESULTS

Of 492 patients with IBS, AGA was positive in 61(12.4 %), hence suspected to have gluten-sensitivity. Of 31 who agreed to participate and followed GFD for 6-weeks, 17 (54.8 %) had complete (>30 % improvement) and 10(32.2 %) had partial (>20 % improvement) response. All 17 complete-responders were given gluten re-challenge for 6-weeks, symptoms recurred in all and hence were confirmed to have NCGS/NCWS. Significant decrease in AGA levels occurred almost in all GFD-responders.

CONCLUSIONS

12.4 % IBS patients have biological evidence of gluten/wheat-sensitivity. Almost 87 % patients with IBS having AGA responded to GFD. The value of AGA may further be explored as a biomarker for screening for the presence of NCGS, before recommending this test for the clinical practice.

Comparative characteristics of fatigue in irritable bowel syndrome and inflammatory bowel disease: A systematic review and meta-analysis

OBJECTIVE

Fatigue is a common symptom in both irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC). This study aimed to distinguish fatigue characteristics in IBS and IBD, two functional and organic disorders.

METHODS

We systematically searched the PubMed and Cochrane Library databases from inception to June 30, 2023, and conducted a meta-analysis to generate precise estimates and 95% confidence intervals. The analyses were stratified by fatigue type, severity, sex, disease phase, and comorbidities, and study quality was assessed using Newcastle-Ottawa Scale (NOS).

RESULTS

Our analysis included 74 data (13 IBS, 31 CD, 30 UC) encompassing 16,689 participants (6484 males, 7402 females, and 2803 unknown). Overall, fatigue prevalence trended higher in IBS (54.5% [95%CI, 44.5-64.6]), followed by CD (49.8% [95%CI, 44.0-55.5]) and UC (43.6% [95%CI, 38.5-48.7]). This pattern persisted across sub-analyses, including general fatigue (63.4% vs. 51.3% vs. 45.3%) and moderate to severe fatigue (73.8% vs. 59.5% vs. 52.7%) for IBS, CD, and UC, respectively. Female predominance was observed in all three diseases (odds ratio: 1.5 in IBS and CD, 1.8 in UC). Fatigue prevalence significantly varied between disease phases (active vs. remission) in CD (61.3% vs. 36.3%) and UC (53.8% vs. 32.6%). Anemia, anxiety/depression, and/or IBS-like symptoms also contributed to fatigue in CD and UC.

CONCLUSIONS

This study is the first extensive comparison of fatigue prevalence and features in IBS, CD, and UC. The findings offer valuable insights for treatment and management, aiding our understanding of functional and organic diseases.

Gut Dysbiosis in Irritable Bowel Syndrome: A Narrative Review on Correlation with Disease Subtypes and Novel Therapeutic Implications

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder characterized by chronic abdominal pain and altered bowel habits. It can be subclassified in different subtypes according to the main clinical manifestation: constipation, diarrhea, mixed, and unclassified. Over the past decade, the role of gut microbiota in IBS has garnered significant attention in the scientific community. Emerging research spotlights the intricate involvement of microbiota dysbiosis in IBS pathogenesis. Studies have demonstrated reduced microbial diversity and stability and specific microbial alterations for each disease subgroup. Microbiota-targeted treatments, such as antibiotics, probiotics, prebiotics, synbiotics, fecal microbiota transplantation, and even diet, offer exciting prospects for managing IBS. However, definitive conclusions are hindered by the heterogeneity of these studies. Further research should focus on elucidating the mechanisms, developing microbiome-based diagnostics, and enabling personalized therapies tailored to an individual's microbiome profile. This review takes a deep dive into the microscopic world inhabiting our guts, and its implications for IBS. Our aim is to elucidate the complex interplay between gut microbiota and each IBS subtype, exploring novel microbiota-targeted treatments and providing a comprehensive overview of the current state of knowledge.

Difficult-to-treat inflammatory bowel disease: results from an international consensus meeting

Many patients with inflammatory bowel disease (IBD) have persistent symptoms and disease activity despite the best available medical or surgical treatments. These patients are commonly referred to as having difficult-to-treat IBD and need additional therapeutic strategies. However, the absence of standard definitions has impeded clinical research efforts and comparisons of data. Under the guidance of the endpoints cluster of the International Organization for the Study of Inflammatory Bowel Disease, we held a consensus meeting to propose a common operative definition for difficult-to-treat IBD. 16 participants from 12 countries voted on 20 statements covering various elements of difficult-to-treat IBD, such as failure of medical and surgical treatments, disease phenotypes, and specific complaints from patients. "Agreement" was defined as at least 75% consensus. The group agreed that difficult-to-treat IBD is defined by the failure of biologics and advanced small molecules with at least two different mechanisms of action, or postoperative recurrence of Crohn's disease after two surgical resections in adults, or one in children. In addition, chronic antibiotic-refractory pouchitis, complex perianal disease, and comorbid psychosocial complications that impair disease management also qualified as difficult-to-treat IBD. Adoption of these criteria could serve to standardise reporting, guide enrolment in clinical trials, and help identify candidates for enhanced treatment strategies.

Irritable bowel syndrome - controversies in diagnosis and management

INTRODUCTION

The irritable bowel syndrome (IBS) is the best-recognized disorder of gut brain interactions (DGBI). However, it is controversial if the Rome IV criteria iteration for IBS diagnosis is fit for purpose.

AREAS COVERED

This review critically evaluates Rome IV criteria for diagnosis of IBS and addresses clinical considerations in IBS treatment and management, including dietary factors, biomarkers, disease mimics, symptom severity, and subtypes. The role of diet in IBS is critically reviewed along with the influence of the microbiota, including small intestinal bacterial overgrowth.

EXPERT OPINION

Emerging data suggest the Rome IV criteria are more suitable for identifying severe IBS and least useful for sub-diagnostic patients who are still likely to benefit from IBS treatment. Despite convincing evidence that IBS symptoms are diet-driven and often postprandial, a relationship to eating is not a Rome IV diagnostic criterion. Few IBS biomarkers have been identified, suggesting the syndrome is too heterogeneous to be measured by a single marker, and combined biomarker, clinical, dietary, and microbial profiling may be needed for objective characterization. With many organic diseases mimicking and overlapping with IBS, it's important clinicians are knowledgable about this to mitigate the risk of missing comorbid organic intestinal disease and to optimally treat IBS symptoms.

Coronavirus disease 2019 and gastrointestinal disorders in children

During the past 3 years, the coronavirus disease 2019 (COVID-19) pandemic has had a great impact on people all over the world. However, it has become evident that disease manifestations and severity differ across age groups. Most children have a milder disease course than adults but possibly more pronounced gastrointestinal (GI) symptoms. Given the child's developing immune system, the impact of COVID-19 on disease development may differ compared to adults. This study reviews the potential bi-directional relationship between COVID-19 and GI diseases in children, focusing on common pediatric conditions such as functional GI disorders (FGID), celiac disease (CeD), and inflammatory bowel disease (IBD). Children with GI diseases, in general, and CeD and IBD, in particular, do not seem to have an increased risk of severe COVID-19, including risks of hospitalization, critical care need, and death. While infections are considered candidate environmental factors in both CeD and IBD pathogenesis, and specific infectious agents are known triggers for FGID, there is still not sufficient evidence to implicate COVID-19 in the development of either of these diseases. However, given the scarcity of data and the possible latency period between environmental triggers and disease development, future investigations in this field are warranted.

Gut microbiota and irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that poses a significant health concern. Although its etiology remains unknown, there is growing evidence that gut dysbiosis is involved in the development and exacerbation of IBS. Previous studies have reported altered microbial diversity, abundance, and composition in IBS patients when compared to controls. However, whether dysbiosis or aberrant changes in the intestinal microbiota can be used as a hallmark of IBS remains inconclusive. We reviewed the literatures on changes in and roles of intestinal microbiota in relation to IBS and discussed various gut microbiota manipulation strategies. Gut microbiota may affect IBS development by regulating the mucosal immune system, brain-gut-microbiome interaction, and intestinal barrier function. The advent of high-throughput multi-omics provides important insights into the pathogenesis of IBS and promotes the development of individualized treatment for IBS. Despite advances in currently available microbiota-directed therapies, large-scale, well-organized, and long-term randomized controlled trials are highly warranted to assess their clinical effects. Overall, gut microbiota alterations play a critical role in the pathophysiology of IBS, and modulation of microbiota has a significant therapeutic potential that requires to be further verified.

Differential Diagnosis of Chronic Diarrhea: An Algorithm to Distinguish Irritable Bowel Syndrome With Diarrhea From Other Organic Gastrointestinal Diseases, With Special Focus on Exocrine Pancreatic Insufficiency

Chronic diarrhea, defined as diarrhea persisting for more than 4 weeks, affects up to 5% of the population regardless of patient age, sex, race, or socioeconomic status. The impact on patient health and quality of life is substantial, and diagnosis and management of these patients have significant economic consequences for health care services. The differential diagnosis of chronic diarrhea is broad, with etiologies including infections, endocrinopathies, maldigestive/malabsorptive conditions, and disorders of gut-brain interaction. The considerable overlap of symptoms across this spectrum makes accurate diagnosis problematic and may lead to delays in diagnosis or misdiagnosis. In this narrative review, we consider the differential diagnosis of chronic diarrhea, focusing on irritable bowel syndrome with diarrhea and exocrine pancreatic insufficiency, two conditions that may present similarly but have very different underlying causes and require significantly different management strategies. We outline a 4-step diagnostic strategy and propose a straightforward algorithm to assist in efficiently differentiating irritable bowel syndrome from exocrine pancreatic insufficiency and other causes of chronic diarrhea. We anticipate that these aids will improve diagnostic accuracy, which ultimately should lead to improvements in patients' health-related quality of life and reduce the societal burden on health care services.

Assessment of Public's Awareness Regarding Irritable Bowel Syndrome in Aseer Region, Saudi Arabia

Irritable bowel syndrome (IBS) is a gastrointestinal disorder characterized by altered bowel habits, abdominal pain, or discomfort. It is a highly prevalent disorder that affects patients' quality of life. A workup is usually required to diagnose IBS, as its differential diagnosis includes some serious conditions such as carcinoma of the colon. The present study aimed to assess the awareness and beliefs of the general population regarding IBS. This study was conducted in the Aseer Region, in the southwestern part of Saudi Arabia. It followed a cross-sectional research design that was conducted during the period from January to March 2021 using a structured self-administered questionnaire to assess the demographic variables in addition to questions to assess participants' awareness and beliefs related to IBS. Following a convenience sample, the study included 779 participants, with 43.3% being male, mostly in the age group 21-30 years (36.7%), and 68.7% being university graduates. Most participants (70.5%) were aware of IBS, and had the correct knowledge about its etiology, symptoms, risk factors, prognosis, and management. It is recommended to conduct various awareness-raising programs regarding IBS to improve the public's knowledge and to decrease functional disabilities and their impact on life.

A review of neuroendocrine immune system abnormalities in IBS based on the brain–gut axis and research progress of acupuncture intervention

Irritable bowel syndrome (IBS) is a common digestive disorder observed in clinics. Current studies suggest that the pathogenesis of the disease is closely related to abnormal brain–gut interactions, hypokinesia, visceral sensory hypersensitivity in the gastrointestinal tract, and alterations in the intestinal microenvironment. However, it is difficult for a single factor to explain the heterogeneity of symptoms. The Rome IV criteria emphasized the holistic biologic-psycho-social model of IBS, suggesting that symptoms of the disease are closely related to neurogastroenterology and various abnormalities in brain–gut interaction. This study comprehensively reviewed the relationship between the brain–gut axis and IBS, the structure of the brain–gut axis, and the relationship between the brain–gut axis and intestinal microenvironment, and discussed the relationship between the abnormal regulation of the nervous system, endocrine system, and immune system and the incidence of IBS on the basis of brain–gut axis. In terms of treatment, acupuncture therapy can regulate the neuroendocrine-immune system of the body and improve the intestinal microenvironment, and it has the advantages of safety, economy, and effectiveness. We study the pathogenesis of IBS from local to global and micro to macro, and review the use of acupuncture to treat the disease as a whole so as to provide new ideas for the treatment of the disease.

Diagnostic yield of colonoscopy for organic disease in irritable bowel syndrome and its risk factors: A meta-analysis

BACKGROUND

Colonoscopy is commonly performed in patients with irritable bowel syndrome (IBS) to rule out organic disease. We performed a meta-analysis to assess the prevalence of organic disease detected at colonoscopy in IBS and its potential risk factors.

METHODS

Medline, Embase, and Web of Science were searched through January 2022. Observational studies that reported diagnostic yield of colonoscopy for organic disease including colorectal cancer (CRC), inflammatory bowel disease (IBD), or microscopic colitis (MC) in adult IBS patients were eligible. Pooled prevalence and risk difference (RD) with 95% confidence intervals (CIs) were calculated.

RESULTS

Of 2490 citations identified, 12 studies were eligible containing 28,630 patients with IBS undergoing colonoscopy. Pooled prevalence of CRC, IBD, and MC in IBS was 0.78%, 4.48%, and 2.35%, respectively. No difference in the yield for CRC, IBD, and MC was seen between IBS and non-IBS patients. CRC was rare in IBS patients without alarm symptoms or younger than 40 years (<0.1%). Pooled Prevalence of CRC (2.47% vs. 0.11%; RD 2.57%, 95% CI 0.37%-4.78%) and IBD (8.86% vs. 4.25%; RD 10.75%, 95% CI 4.81%-16.68%) was significantly higher in IBS patients with alarm symptoms compared with those without. IBD and MC were more likely to be detected at colonoscopy in IBS-D compared with IBS-C. The prevalence of CRC and MC was higher in IBS patients with older age than younger age.

CONCLUSION

We provide the first pooled estimate of yield of colonoscopy in IBS and its risk factors, which may be used to inform clinical decision and support guidelines.

The Causal Association of Irritable Bowel Syndrome with Multiple Disease Outcomes: A Phenome-Wide Mendelian Randomization Study

BACKGROUND

This study aimed to identify novel associations between irritable bowel syndrome (IBS) and a broad range of outcomes.

METHODS

In total, 346,352 white participants in the U.K. Biobank were randomly divided into two halves, in which a genome-wide association study (GWAS) of IBS and a polygenic risk score (PRS) analysis of IBS using GWAS summary statistics were conducted, respectively. A phenome-wide association study (PheWAS) based on the PRS of IBS was performed to identify disease outcomes associated with IBS. Then, the causalities of these associations were tested by both one-sample (individual-level data in U.K. Biobank) and two-sample (publicly available summary statistics) Mendelian randomization (MR). Sex-stratified PheWAS-MR analyses were performed in male and female, separately.

RESULTS

Our PheWAS identified five diseases associated with genetically predicted IBS. Conventional MR confirmed these causal associations between IBS and depression (OR: 1.07, 95%CI: 1.01-1.14, p = 0.02), diverticular diseases of the intestine (OR: 1.13, 95%CI: 1.08-1.19, p = 3.00 × 10^-6), gastro-esophageal reflux disease (OR: 1.09, 95%CI: 1.05-1.13, p = 3.72 × 10^-5), dyspepsia (OR: 1.21, 95%CI: 1.13-1.30, p = 9.28 × 10^-8), and diaphragmatic hernia (OR: 1.10, 95%CI: 1.05-1.15, p = 2.75 × 10^-5). The causality of these associations was observed in female only, but not men.

CONCLUSIONS

Increased risks of IBS is found to cause a series of disease outcomes. Our findings support further investigation on the clinical relevance of increased IBS risks with mental and digestive disorders.

Inflammatory bowel disease is causally related to irritable bowel syndrome: a bidirectional two-sample Mendelian randomization study

Introduction

Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are lifelong digestive diseases that severely impact patients' quality of life. The existence of a causal association between IBS and IBD remains unclear. This study aimed to determine the direction of causality between IBD and IBS by quantifying their genome-wide genetic associations and performing bidirectional two-sample Mendelian randomization (MR) analyses.

Methods

Genome-wide association studies (GWAS) among a predominantly European patient cohort identified independent genetic variants associated with IBS and IBD. Two separate databases (a large GWAS meta-analysis and the FinnGen cohort) for both IBS and IBD were consulted to retrieve statistics on instrument-outcome associations. MR analyses included inverse-variance-weighted, weighted-median, MR-Egger regression, MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO) methods, and sensitivity analyses were performed. The MR analyses were carried out for each outcome data, followed by a fixed-effect meta-analysis.

Results

Genetically predicted IBD was associated with an increased risk of IBS. Odds ratios (95% confidence intervals) for samples of 211,551 (17,302 individuals with IBD), 192,789 (7,476 Crohn's disease cases), and 201,143 (10,293 ulcerative colitis cases) individuals were 1.20 (1.00, 1.04), 1.02 (1.01, 1.03), and 1.01 (0.99, 1.03), respectively. After outlier correction using MR-PRESSO, the odds ratio for ulcerative colitis was 1.03 (1.02, 1.05) (p = 0.001). However, an association between genetically influenced IBS and IBD was not identified.

Discussion

This study confirms that IBD is causally related to IBS, which may interfere with the diagnosis and treatment of both diseases.

Effect of prebiotics, probiotics, and synbiotics on gastrointestinal outcomes in healthy adults and active adults at rest and in response to exercise-A systematic literature review

Introduction

A systematic literature search was undertaken to assess the impact of pre-, pro-, and syn-biotic supplementation on measures of gastrointestinal status at rest and in response to acute exercise.

Methods

Six databases (Ovid MEDLINE, EMBASE, Cinahl, SportsDISCUS, Web of Science, and Scopus) were used. Included were human research studies in healthy sedentary adults, and healthy active adults, involving supplementation and control or placebo groups. Sedentary individuals with non-communicable disease risk or established gastrointestinal inflammatory or functional diseases/disorders were excluded.

Results

A total of n = 1,204 participants were included from n = 37 papers reported resting outcomes, and n = 13 reported exercise-induced gastrointestinal syndrome (EIGS) outcomes. No supplement improved gastrointestinal permeability or gastrointestinal symptoms (GIS), and systemic endotoxemia at rest. Only modest positive changes in inflammatory cytokine profiles were observed in n = 3/15 studies at rest. Prebiotic studies (n = 4/5) reported significantly increased resting fecal Bifidobacteria, but no consistent differences in other microbes. Probiotic studies (n = 4/9) increased the supplemented bacterial species-strain. Only arabinoxylan oligosaccharide supplementation increased total fecal short chain fatty acid (SCFA) and butyrate concentrations. In response to exercise, probiotics did not substantially influence epithelial injury and permeability, systemic endotoxin profile, or GIS. Two studies reported reduced systemic inflammatory cytokine responses to exercise. Probiotic supplementation did not substantially influence GIS during exercise.

Discussion

Synbiotic outcomes resembled probiotics, likely due to the minimal dose of prebiotic included. Methodological issues and high risk of bias were identified in several studies, using the Cochrane Risk of Bias Assessment Tool. A major limitation in the majority of included studies was the lack of a comprehensive approach of well-validated biomarkers specific to gastrointestinal outcomes and many included studies featured small sample sizes. Prebiotic supplementation can influence gut microbial composition and SCFA concentration; whereas probiotics increase the supplemented species-strain, with minimal effect on SCFA, and no effect on any other gastrointestinal status marker at rest. Probiotic and synbiotic supplementation does not substantially reduce epithelial injury and permeability, systemic endotoxin and inflammatory cytokine profiles, or GIS in response to acute exercise.

Coptisine attenuates post‑infectious IBS via Nrf2‑dependent inhibition of the NLPR3 inflammasome

Inhibition of the activation of the NLR family pyrin domain‑containing 3 (NLRP3) inflammasome has previously been reported to confer protection against post‑infectious irritable bowel syndrome (PI‑IBS). Coptisine, the second most abundant isoquinoline alkaloid in Coptis chinensis, can inhibit NLRP3 inflammasome activation; however, whether coptisine exhibits protective effects against PI‑IBS remains unclear. In the present study, coptisine significantly reduced gastrointestinal motility and abdominal withdrawal reflex scores in a PI‑IBS rat model that was induced using intragastric administration of Trichinella spiralis larvae. Coptisine treatment significantly decreased the protein levels of oxidative stress markers, 4‑hydroxynonenal, protein carbonyl and 8‑hydroxy‑2'deoxyguanosine, and proinflammatory cytokines, TNF‑α, IL‑1β and IL‑18 in the colon of PI‑IBS rats. Moreover, coptisine treatment significantly increased nuclear factor erythroid 2‑related factor 2 (Nrf2) nuclear translocation and heme oxygenase‑1 protein expression levels, while significantly downregulating the protein expression levels of NLRP3, apoptosis‑associated speck‑like protein containing a CARD and caspase‑1 in the colons of PI‑IBS rats. It is important to note that the anti‑inflammatory effects of coptisine were blocked by the Nrf2 inhibitor ML385. In summary, the present study indicated that coptisine potentially attenuated PI‑IBS in rats via Nrf2‑dependent inhibition of the NLPR3 inflammasome.

Stress, Resilience, and the Brain-Gut Axis: Why is Psychogastroenterology Important for all Digestive Disorders?

In this review article, we show that stress and resilience play an integral role in the brain-gut axis and are critical to symptom expression across all digestive disorders. The relationship between stress, coping, and resilience provides a mechanistic basis for brain-gut behavior therapies. Psychogastroenterology is the field best equipped to translate and mitigate these constructs as part of patient care across all digestive disorders.

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.

A Biomarker-Responsive Nanosystem with Colon-Targeted Delivery for Ulcerative Colitis's Detection and Treatment with Optoacoustic/NIR-II Fluorescence Imaging

Ulcerative colitis (UC) is a prevalent idiopathic inflammatory disease which causes such complications as intestinal perforation, obstruction, and bleeding, and thus deleteriously impacting people's normal work and quality of life. Hence, accurate diagnosis of UC is crucial in terms of planning optimal treatment plan. Herein, a pH/reactive oxygen species (ROS) dual-responsive nanosystem (BM@EP) is developed for UC's detection and therapy. BM@EP is composed of a chromophore-drug dyad and the enteric coating. The chromophore-drug dyad (BOD-XT-DHM) is synthesized by linking the chromophore (BOD-XT-BOH) and a flavonoid drug (dihydromyricetin DHM) through boronate ester bond. The enteric coating includes Eudragit S100 and poly(lactic-co-glycolic acid) (PLGA), the former is commonly employed as a pH-dependent polymer coating excipient so as to attain colon-targeted delivery, and the latter has been widely used as an excipient for the controlled-extended release. After oral administration, BM@EP delivers the dyad (BOD-XT-DHM) into the colon and releases the dyad molecules by being triggered by the alkaline pH in t colon, thereafter upon being stimulated by overexpressed H₂ O₂ in the inflamed colon, the boronate bond in the dyad is broken down and correspondingly the drug DHM is released for UC therapy, simultaneously the chromophore is released for near-infrared second window (NIR-II) fluorescence and optoacoustic imaging for UC diagnosis and recovery evaluation.

Functional Abdominal Cramping Pain: Expert Practical Guidance

Functional abdominal cramping pain (FACP) is a common complaint, which may present either on its own or in association with a functional gastrointestinal disorder. It is likely caused by a variety of, probably partly unknown, etiologies. Effective management of FACP can be challenging owing to the lack of usable diagnostic tools and the availability of a diverse range of treatment approaches. Practical guidance for their selection and use is limited. The objective of this article is to present a working definition of FACP based on expert consensus, and to propose practical strategies for the diagnosis and management of this condition for physicians, pharmacists, and patients. A panel of experts on functional gastrointestinal disorders was convened to participate in workshop activities aimed at defining FACP and agreeing upon a recommended sequence of diagnostic criteria and management recommendations. The key principles forming the foundation of the definition of FACP and suggested management algorithms include the primacy of cramping pain as the distinguishing symptom; the importance of recognizing and acting upon alarm signals of potential structural disease; the recognition of known causes that might be addressed through lifestyle adjustment; and the central role of antispasmodics in the treatment of FACP. The proposed algorithm is intended to assist physicians in reaching a meaningful diagnostic endpoint based on patient-reported symptoms of FACP. We also discuss how this algorithm may be adapted for use by pharmacists and patients.

Celiac Disease and Gallbladder: Pathophysiological Aspects and Clinical Issues

Background: Celiac Disease (CD) is an immune-mediated disorder which primarily affects the small intestine; however, extra-intestinal organs are often affected by the pathological process, too. As regards the digestive system, liver alterations in CD patients have been widely described, which can also extend to the biliary tract. Notably, gallbladder function can be altered in CD patients. In this review, we specifically analyze and summarize the main pathophysiological aspects and clinical evidence of gallbladder dysfunction in CD patients, in order to discuss the potential medical complications and clinical research gaps. In addition to some perturbations of bile composition, CD patients can develop gallbladder dysmotility, which mainly expresses with an impaired emptying during the digestive phase. The main pathophysiological determinant is a perturbation of cholecystokinin secretion by the specific duodenal enteroendocrine cells in response to the appropriate nutrient stimulation in CD patients. This situation appears to be reversible with a gluten-free diet in most cases. Despite this gallbladder impairment, CD patients do not seem to be more predisposed to gallbladder complications, such as calculous and acalculous cholecystitis. However, very few clinical studies have actively investigated these clinical aspects, which may not be completely evidenced so far; alternatively, the substantial improvements in the last two decades regarding CD diagnosis, which have reduced the diagnostic delay (and related dietary treatment), may have lessened the potential clinical consequences of CD-related gallbladder dysfunction. Specific clinical studies focused on these aspects are needed for a better understanding of the clinical implications of gallbladder alterations in CD patients.

A Low FODMAP Diet Reduces Symptoms in Treated Celiac Patients With Ongoing Symptoms-A Randomized Controlled Trial

BACKGROUND & AIMS

A gluten-free diet usually leads to mucosal remission in celiac disease, but persistent symptoms are common. A low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet is an established treatment for irritable bowel syndrome (IBS). We have assessed the efficacy of a moderately low FODMAP diet on persistent symptoms in treated celiac patients.

METHODS

A randomized controlled trial was performed from 2018 to 2019 in 70 adults with biopsy-proven celiac disease. Inclusion criteria were as follows: persistent gastrointestinal symptoms defined by a Gastrointestinal Symptom Rating Scale (GSRS)-IBS version score of 30 or higher, gluten-free diet adherence for 12 months or longer, and serologic and mucosal remission. Participants were randomized to a low FODMAP-gluten-free diet (intervention) or usual gluten-free diet (control). The GSRS-IBS score was recorded at baseline and at weeks 1 to 4, and the Celiac Symptom Index at baseline and at week 4. Statistics included marginal models for repeated data and analyses of covariance.

RESULTS

We included 34 participants in the intervention group and 36 in the control group. Time development of GSRS-IBS total scores differed significantly between the groups (P_interaction < .001), evident after 1 week (mean difference in intervention vs control, -8.2; 95% CI, -11.5 to -5.0) and persisting through week 4 (mean difference in intervention vs control, -10.8; 95% CI, -14.8 to -6.8). Moreover, significantly lower scores were found for the dimensions of pain, bloating, diarrhea, and satiety (P_interaction ≤ .04), but not constipation (P_interaction = .43). FODMAP intake during the intervention was moderately low (mean, 8.1 g/d; 95% CI, 6.7-9.3 g/d). The Celiac Symptom Index was significantly lower in the intervention group at week 4 (mean difference, -5.8; 95% CI, -9.6 to -2.0).

CONCLUSIONS

A short-term moderately low FODMAP diet significantly reduced gastrointestinal symptoms and increased celiac disease-specific health, and should be considered for the management of persistent symptoms in celiac disease.

CLINICALTRIALS

gov: NCT03678935.

Factors related to irritable bowel syndrome and differences among subtypes: A cross-sectional study in the UK Biobank

Background: Irritable bowel syndrome (IBS) reduces patients' quality of life and causes great burdens due to its unclear pathogenesis and criteria for diagnosis. This study aimed to explore the differences in prevalence and the influencing factors for IBS and its subtypes. Methods: The UK Biobank surveyed 174,771 adult participants who completed the Digestive Health Questionnaire (DHQ) through emails and websites. DHQ included the Rome III criteria, IBS symptom severity score, and Patient Health Questionnaire 12 Somatic Symptom score. The UK Biobank also asked regarding previous IBS diagnosis, diagnosis for post-infectious IBS (PI-IBS), and environmental exposures and associated conditions (including anxiety or depression, based on treatment sought or offered). Pearson's Chi-squared test or Wilcoxon's rank-sum test was used for potential associations. Binary logic regression based on sex stratification was used to examine associations between selected factors and IBS and its subtypes. Results: This study included 31,918 participants who met the Rome III criteria for IBS. The pooled prevalence of IBS in the UK Biobank was 18.3%, with mixed IBS as the predominant subtype (59.0%), followed by diarrhea-predominant IBS (25.1%), constipation-predominant IBS (14.7%), and untyped IBS (1.1%). IBS was significantly associated with somatization (male: OR = 5.326, 95% CI = 4.863-5.832; female: OR = 4.738, 95% CI = 4.498-4.992) and coeliac disease (male: OR = 4.107, 95% CI = 3.132-5.385; female: OR = 3.783, 95% CI = 3.310-4.323). Differences in antibiotics and mental status were presented among subtypes and sex. Furthermore, 1,787 individuals were diagnosed with PI-IBS in the group of patients with IBS. The prevalence of PI-IBS in IBS was 16.6% in the UK Biobank, and it was characterized by diarrhea, fever, bloody diarrhea, and vomiting. Conclusion: Somatization and coeliac disease are primary risk factors for IBS. Distinguishing differential risk factors is critical for the precise diagnosis and treatment of IBS subtypes, particularly sex-specific differences in mental health status. General practitioners should focus on the treatment according to IBS subtypes.

The Effect of Serine Protease Inhibitors on Visceral Pain in Different Rodent Models With an Intestinal Insult

Background: Serine proteases are believed to play a key role in the origin of abdominal pain in IBD and IBS. We previously demonstrated a reduction of visceral pain in a post-inflammatory IBS rat model after a single intraperitoneal or intracolonic administration of a serine protease inhibitor. The aim of this study was to investigate the efficacy of serine protease inhibition on visceral pain in two different animal models involving a colonic insult based either on acute inflammation or on neonatal irritation. Moreover, protease profiling was explored in the acute colitis model. Methods: An acute 2,4,6-trinitrobenzenesulphonic acid (TNBS) colitis rat model and a chronic neonatal acetic acid mouse model were used in this study. Visceral sensitivity was quantified by visceromotor responses (VMRs) to colorectal distension, 30 min after intraperitoneal administration of the serine protease inhibitors nafamostat, UAMC-00050 or their vehicles. Colonic samples from acute colitis rats were used to quantify the mRNA expression of a panel of serine proteases and mast cell tryptase by immunohistochemistry. Finally, proteolytic activities in colonic and fecal samples were characterized using fluorogenic substrates. Key Results: We showed a significant and pressure-dependent increase in visceral hypersensitivity in acute colitis and neonatal acetic acid models. UAMC-00050 and nafamostat significantly reduced VMRs in both animal models. In acute colitis rats, the administration of a serine protease inhibitor did not affect the inflammatory parameters. Protease profiling of these acute colitis animals revealed an increased tryptase immunoreactivity and a downregulation of matriptase at the mRNA level after inflammation. The administration of UAMC-00050 resulted in a decreased elastase-like activity in the colon associated with a significantly increased elastase-like activity in fecal samples of acute colitis animals. Conclusion: In conclusion, our results suggest that serine proteases play an important role in visceral hypersensitivity in an acute TNBS colitis model in rats and a neonatal acetic acid model in mice. Moreover, we hypothesize a potential mechanism of action of UAMC-00050 via the alteration of elastase-like proteolytic activity in acute inflammation. Taken together, we provided fundamental evidence for serine protease inhibitors as a promising new therapeutic strategy for abdominal pain in gastrointestinal diseases.

Functional Gastrointestinal Disorders and Associated Health Impairment in Individuals with Celiac Disease

BACKGROUND & AIMS

Individuals with celiac disease (CD) can experience persisting gastrointestinal symptoms despite adhering to a gluten-free diet (GFD). This may be due to functional gastrointestinal disorders (FGIDs), although there is little data on its prevalence and associated factors.

METHODS

An online health questionnaire was completed by adult members of Celiac UK in October 2018. The survey included validated questions on Rome IV FGIDs, nongastrointestinal somatic symptoms, anxiety, depression, quality of life, health care use, GFD duration, and its adherence using the celiac dietary adherence test score (with a value ≤ 13 indicating optimal adherence). The prevalence of FGIDs and associated health impairment in the celiac cohort was compared against an age- and sex-matched population-based control group.

RESULTS

Of the 863 individuals with CD (73% female; mean age, 61 years), all were taking a GFD for at least 1 year, with 96% declaring that they have been on the diet for 2 or more years (2-4 years, 20%; ≥5 years, 76%). The adherence to a GFD was deemed optimal in 61% (n = 523), with the remaining 39% (n = 340) nonadherent. Those adhering to a GFD fulfilled criteria for a FGID in approximately one-half of cases, although this was significantly lower than nonadherent subjects (51% vs 75%; odds ratio [OR], 2.0; P < .001). However, the prevalence of FGIDs in GFD-adherent subjects was significantly higher than in matched population-based controls (35%; OR, 2.0; P < .001). This was accounted for by functional bowel (46% vs 31%; OR, 1.9; P < .0001) and anorectal disorders (14.5% vs 9.3%; OR, 1.7; P = .02) but not functional esophageal (7.6% vs 6.1%; P = .36) or gastroduodenal disorders (8.7% vs 7.4%; P = .47). Finally, GFD-adherent subjects with FGIDs were significantly more likely than their counterparts without FGIDs to have abnormal levels of anxiety (5% vs 2%; OR, 2.8; P = .04), depression (7% vs 2%; OR, 3.6; P = .01), somatization (31% vs 8%; OR, 5.1; P < .0001), and reduced quality of life (P < .0001).

CONCLUSION

One in 2 people with CD, despite having been on a GFD for a number of years and demonstrating optimal adherence, have ongoing symptoms compatible with a Rome IV FGID. This is 2-fold the odds of FGIDs seen in age- and sex-matched controls. The presence of FGIDs is associated with significant health impairment, including psychological comorbidity. Addressing disorders of gut-brain interaction might improve outcomes in this specific group of patients.

Genetically engineered pH-responsive silk sericin nanospheres with efficient therapeutic effect on ulcerative colitis

Ulcerative colitis (UC) is one type of inflammatory bowel disease (IBD) and lactoferrin (LF) is a promising protein drug to treat UC. However, targeted LF delivery to optimize bioavailability, targeting and effectiveness remains a challenge. Here, we report an effective strategy to fabricate silk sericin nanospheres systems for the delivery of recombinant human lactoferrin (SS-NS-rhLF). The system is based on the use of optimized transgenic silkworms to generate genetically engineered silk fibers (rhLF-silks). The rhLF silks were used for fabricating SS-NS-rhLF by ethanol precipitation. The SS-NS-rhLF were stable with a spherical morphology with an average diameter of 123 nm. The negatively charged sericins in a pH ≥ 5.5 environment achieved specific targeting of the SS-NS-rhLF to positively charged colonic sites. The SS-NS-rhLF achieved efficient uptake by cells in the inflamed colon of mice when compared to free lactoferrin in solution (SOL-rhLF). Furthermore, oral administration of the SS-NS-rhLF with low dose of rhLF significantly relived symptoms of UC in mice and achieved comparable therapeutic effect to the high dose of SOL-rhLF by supporting the reformation of cell structure and length of colon tissue, reducing the release of inflammatory factors, inhibiting the activation of the NF-κB inflammatory pathway, and maintaining a stable intestinal microbial population in mice. These results showed that the SS-NS-rhLF is a promising system for colitis treatment. STATEMENT OF SIGNIFICANCE: Targeting and effective delivery of multiple biological functional protein human lactoferrin (rhLF) is a promising strategy to treat ulcerative colitis in the clinic. Here, rhLF-transgenic silk cocoons were used to fabricate a rhLF-sericin nanosphere delivery system (SS-NS-rhLF). The fabricated SS-NS-rhLF showed identical spherical morphology, stable structure, sustainable rhLF release, efficient cell uptake and negative charge in an environment of pH above 5.5, thus realized the specific targeting to the positively charged colonic sites to treat UC mice through oral administration. The therapeutic effect of SS-NS-rhLF with a low rhLF dose in the UC mice was comparable to the high dose of free rhLF treatment in solution form, suggesting that the SS-NS-rhLF is a promising system for colitis treatment.

Risk of Colorectal Cancer in Patients With Irritable Bowel Syndrome: A Meta-Analysis of Population-Based Observational Studies

Background and Aims

Evidence on the association between irritable bowel syndrome (IBS) and colorectal cancer (CRC) risk is inconsistent. Therefore, we aimed to examine whether IBS leads to an increased risk for CRC using a systematic review and meta-analysis approach.

Methods

PubMed, Embase, and Web of Science were systematically searched to identify all relevant literature published through July 30, 2021. The pooled risk ratios (RRs) and corresponding 95% confidence intervals (CIs) for CRC after diagnosis of IBS were computed using random-and fixed-effects models and stratified by age, follow-up time, gender, and study design. The quality of included studies was assessed by the Newcastle-Ottawa scale.

Results

We included six studies consisting of 1,085,024 participants. Overall, the risk of detecting CRC after the initial IBS diagnosis was significantly higher than non-IBS controls (RR = 1.52, 95% CI: 1.04-2.22, P = 0.032). The peak of elevated risk occurred within the first year of IBS diagnosis (RR = 6.84, 95% CI: 3.70-12.65, P < 0.001), and after 1 year, the risk of CRC was similar to that of the general population (RR = 1.02, 95% CI: 0.88-1.18, P = 0.813). Notably, we found that the RR of CRC was more significant in IBS patients younger than 50 years compared to those older than 50 years (RR = 2.03, 95% CI: 1.17-3.53, P = 0.012 vs. 1.28, 95%CI: 0.94-1.75, P = 0.118, respectively). Gender and study design did not affect the results.

Conclusion

The risk of CRC within one year of the initial IBS diagnosis was increased approximately six-fold, whereas the long-term risk was not increased. However, current evidence does not support that IBS leads to an increased incidence of CRC, and the early excess risk is more likely attributable to misclassification resulting from overlapping symptoms rather than causation. Clinicians must remain vigilant for the CRC risk in patients younger than 50 years with IBS-like symptoms to avoid delaying necessary screening.

Systematic review and meta-analysis: the advantage of endoscopic Mayo score 0 over 1 in patients with ulcerative colitis

Background

Mucosal healing (MH) evaluated by endoscopy is a novel target of therapy in UC as it is associated with improved long-term outcomes. It is defined based on the Mayo endoscopic score (MES), but it is still to define whether a value of MES 0 or 1 should be the target. The purpose of this paper is to present the results of a systematic review with meta-analysis which compares long-term outcomes of patients in steroid-free clinical remission with MES 0 with those with MES 1.

Methods

A systematic electronic search of the literature was performed using Medline, Scopus, and CENTRAL through December 2020 (PROSPERO n:CRD42020179333). The studies concerned UC patients, in steroid-free clinical remission, with MES of 0 or 1, and with at least 12-months of follow-up.

Results

Out of 4611 citations, 15 eligible studies were identified. Increases in clinical relapse among patients with MES 1 were observed in all the studies included in this review, suggesting that MES of 1 have a higher risk of relapse than a score of 0. MES 0 patients displayed a lower risk of clinical relapse (OR 0.33; 95% CI 0.26–0.43; I² 13%) irrespective of the follow-up time (12-months or longer). On the other hand, no differences were found comparing MES 0 versus MES 1 about the risk of hospitalization or colectomy.

Conclusions

MES 0 is associated with a lower rate of clinical relapse than is MES 1. For this reason, MES 0, rather than MES 0–1, should be considered the therapeutic target for patients with UC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02157-5.

Moxibustion for diarrhea in COVID-19: A protocol for systematic review and meta-analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease that is often accompanied by diarrhea, patients with symptoms such as diarrhea are more likely to develop severe pneumonia, while diarrhea is the most prominent among atypical symptoms. The incidence of diarrhea in COVID-19 patients is 2.0% to 49.5%. Moxibustion has been proven to have a therapeutic effect on diarrhea; however, there is no high-quality evidence on moxibustion for diarrhea in COVID-19 patients. This study was designed to evaluate the effectiveness and safety of moxibustion for the treatment of diarrhea in patients with COVID-19.

METHODS

Randomized controlled trials from December 2019 to December 2021 will be included without restrictions on language or publication date. PubMed, EMBASE, Cochrane Library, Web of Science, Chinese Biomedical Databases, China National Knowledge Infrastructure, Wanfang database, and VIP database will be searched. Two researchers will independently select studies, extract data and evaluate study quality. Cochrane risk of bias tool for randomized trials will be used to assess the risk of bias of included studies. Statistical analyses will be performed using the Review Manager V.5.3 and stata 14.0.

RESULTS

The results of this meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This study will provide evidence for whether moxibustion therapy is beneficial to the treatment of diarrhea in COVID-19.

ETHICS AND DISSEMINATION

Ethical approval is not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and shared on social media platforms. This review would be disseminated in a peer-reviewed journal or conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42022302933.

Overlap between irritable bowel syndrome and common gastrointestinal diagnoses: a retrospective cohort study of 29,553 outpatients in Germany

Background

Irritable bowel syndrome (IBS) represents the most common functional disorder of the gastrointestinal tract. Many patients with IBS display complex gastrointestinal (GI) symptoms leading to overlapping diagnosis of IBS and other GI diseases in many patients.

Methods

Using the Disease Analyzer database (IQVIA) featuring patients treated within 2010 and 2019 within 1240 general practices in Germany, we analyzed the prevalence of common GI diseases within 12 months prior to and after the first diagnosis of IBS.

Results

65,569 patients with an initial diagnosis of IBS were included into the analysis. Out of these, 29,553 patients had an observation time of at least 12 months prior to the first IBS diagnosis and at least 12 months after the first IBS diagnosis. Mean age was 48.8 (SD: 18.4) years, 65.0% were female. Notably, 16,164 (55%) of these patients had at least one preexisting diagnosis of another GI diseases within 12 months prior to the first IBS diagnosis. Most common overlapping diagnoses were intestinal infectious diseases (26%), gastritis/ duodenitis (21%), diseases of the esophagus (15%), non-infectious enteritis or colitis (7.4%), functional dyspepsia (6%) and ulcers (1.0%). Additionally, 12,048 (41%) received one of these diagnosis within 12 months after the first IBS diagnosis.

Conclusion

Our data provide evidence for a high overlap between IBS and other GI diagnoses. Moreover, we show that IBS is frequently diagnosed in patients with preexisting GI diseases, potentially putting into question the validity of IBS diagnosis at least in some cases.

Public Awareness of Bowel Cancer Risk Factors, Symptoms and Screening in Tasmania, Australia: A Cross-Sectional Study

Tasmania has one of the highest bowel cancer incidence and death rates in the world. Public awareness of risk factors, symptoms, and early detection of bowel cancer is important for minimising the burden of disease. This study measured awareness levels of bowel cancer risk factors, symptoms and screening in Tasmania. An online survey of 3703 participants aged 18 years and older found that alcohol consumption, low physical activity levels, and having diabetes were the least known risk factors for bowel cancer. Over half of all participants were unaware the risk of bowel cancer increased with age, and 53 percent were not confident they would notice a bowel cancer symptom. Over a third of survey respondents did not know that screening commenced at the age of 50. The results indicate that a targeted campaign to increase bowel cancer awareness in Tasmania may help reduce the high rates of morbidity and mortality from the disease.

OUP accepted manuscript

Microscopic colitis (MC) is a chronic inflammatory disease of the large intestine and as a relatively late recognized condition, its relationship with other disorders of the gastrointestinal tract is gradually being understood and investigated. As a multifactorial disease, MC interacts with inflammatory bowel disease, celiac disease, and irritable bowel syndrome through genetic overlap, immunological factors, and gut microflora. The risk of colorectal cancer was significantly lower in MC, gastrointestinal infections increased the risk of developing MC, and there was an inverse association between Helicobacter pylori infection and MC. A variety of associations are found between MC and other gastrointestinal disorders, where aspects such as genetic effects, resemblance of immunological profiles, and intestinal microecology are potential mechanisms behind the relationships. Clinicians should be aware of these connections to achieve a better understanding and management of MC.

Moxibustion for diarrhea-predominant irritable bowel syndrome: A protocol for systematic review and network meta-analysis

BACKGROUND

Irritable bowel syndrome (IBS) is commonly accompanied by intestinal dysfunction, and diarrhea-predominant irritable bowel syndrome accounts for approximately 23.4% of all cases of IBS. The purpose of this study was to evaluate the efficacy and safety of moxibustion in the treatment of diarrhea-predominant irritable bowel syndrome.

METHODS

According to the retrieval strategies, randomized controlled trials (RCTs) on moxibustion therapies for IBS-D will be obtained from the China National Knowledge Infrastructure, WanFang Data, Chinese Scientific Journals Database, PubMed, Embase, and Cochrane Library, regardless of publication date or language. Studies will be screened based on inclusion and exclusion criteria, and the Cochrane risk bias assessment tool will be used to evaluate the quality of the literature. The network meta-analysis will be performed with the Markov chain Monte Carlo method and carried out with Stata 14.2 and WinBUGS 1.4.3 software. Ultimately, the quality of the evidence obtained from the results will be evaluated.

RESULTS

This study will evaluate whether moxibustion therapy can effectively treat diarrhea-predominant irritable bowel syndrome.

CONCLUSION

This study will provide evidence for whether moxibustion therapy is beneficial to the treatment of human diarrhea-predominant irritable bowel syndrome.

INPLASY REGISTRATION NUMBER

INPLASY202180003.

Increased psychological distress and somatization in patients with irritable bowel syndrome compared with functional diarrhea or functional constipation, based on Rome IV criteria

BACKGROUND

The Rome IV criteria for disorders of gut-brain interaction define irritable bowel syndrome (IBS) as a functional bowel disorder associated with frequent abdominal pain of at least 1 day per week. In contrast, functional diarrhea (FD) and functional constipation (FC) are relatively painless. We compared differences in mood and somatization between Rome IV IBS and FC/FD.

METHODS

A total of 567 patients with Rome IV defined IBS or FD/FC completed a baseline questionnaire on demographics, abdominal pain frequency, mood (hospital anxiety and depression scale, HADS), and somatization (patient health questionnaire, PHQ-12). The primary analysis compared differences in mood and somatization between IBS and FC/FD, and the relative influence of abdominal pain frequency on these extra-intestinal symptoms. The secondary analysis evaluated differences across individual IBS subtypes, and also between FC and FD.

KEY RESULTS

Patients with IBS-in comparison to those with FC/FD-had significantly higher mean PHQ-12 somatization scores (9.1 vs. 5.4), more somatic symptoms (6.0 vs. 4.3), abnormally high somatization levels (16% vs. 3%), higher HADS score (15.0 vs. 11.7), and clinically abnormal levels of anxiety (38% vs. 20%) and depression (17% vs. 10%). Increasing abdominal pain frequency correlated positively with PHQ-12, number of somatic symptoms, and HADS; p < 0.001. No differences in mood and somatization scores were seen between individual IBS subtypes, and nor between FC and FD.

CONCLUSION & INFERENCES

Based on the Rome IV criteria, IBS is associated with increased levels of psychological distress and somatization compared with FD or FC. Patients reporting frequent abdominal pain should be comprehensively screened for psychosomatic disorders, with psychological therapies considered early in the disease course.

Allergy-related diseases in childhood and risk for abdominal pain-related functional gastrointestinal disorders at 16 years-a birth cohort study

BACKGROUND

Studies on allergy-related diseases in relation to abdominal pain-related functional gastrointestinal disorders (AP-FGIDs) in children are few and results are contradictory. We examined the associations between childhood allergy-related diseases and adolescent AP-FGIDs in general and irritable bowel syndrome (IBS) in particular.

METHOD

Prospective population-based birth cohort study of 4089 children born in Sweden 1994-1996. We analysed data from 2949 children with complete follow-up at 16 years (y) and no diagnosis of inflammatory bowel disease or coeliac disease at 12y or 16y. Asthma, rhinitis, eczema, and food hypersensitivity (FH) were assessed through questionnaires at 1-2y, 4y, 8y, 12y, and 16y. AP-FGIDs and IBS were assessed through questionnaires at 16y and defined according to the Rome III criteria. Associations between childhood allergy-related diseases and any AP-FGID and IBS and 16y respectively were examined using binomial generalized linear models with a log link function and described as relative risk with 95% confidence intervals.

RESULTS

The prevalence of any AP-FGID and IBS at 16y were 12.0% and 6.0% respectively. Eczema at 1-2y, 4y, and 8y, and FH at 12y and 16y were associated with an increased risk for any AP-FGID at 16y. Asthma and FH at 12y and 16y were associated with an increased risk for IBS at 16y. The relative risk for IBS at 16y increased with increasing number of concurrent allergy-related diseases at 16y, but linear trend for relative risk was only borderline statistically significant (P for trend = 0.05).

CONCLUSIONS

This prospective population-based study demonstrated positive associations between childhood allergy-related diseases and adolescent AP-FGIDs, including IBS, implicating shared pathophysiology among these disorders.

Utilizing Probiotics for the Prevention and Treatment of Gastrointestinal Diseases

Probiotics are heavily advertised to promote a healthy gastrointestinal tract and boost the immune system. This review article summarizes the history and diversity of probiotics, outlines conventional in vitro assays and in vivo models, assesses the pharmacologic effects of probiotic and pharmaceutical co-administration, and the broad impact of clinical probiotic utilization for gastrointestinal disease indications.