Screening for Celiac Disease in Irritable Bowel Syndrome: An Updated Systematic Review and Meta-analysis

Rifaximin and alternative agents in the management of irritable bowel syndrome: A comprehensive review

Rifaximin, a broad-spectrum antibiotic, boasts a unique chemical composition and pharmacokinetic profile, rendering it highly effective in treating irritable bowel syndrome (IBS). Its minimal systemic absorption confines its impact to the gastrointestinal (GI) tract, where it yields significant therapeutic benefits. This review examines rifaximin's physico-chemical attributes and its role in managing IBS symptoms. Its molecular structure facilitates intestinal lumen retention postoral administration, minimizing systemic exposure and adverse effects. This targeted action is crucial in addressing the gut microbiota's role in IBS pathophysiology. By modifying microbial populations and their metabolite production, rifaximin mitigates symptoms like bloating, irregular bowel habits, and abdominal pain associated with IBS. It achieves this by reducing pathogenic bacteria and altering bacterial metabolism, enhancing mucosal and immune function. Clinical trials affirm rifaximin's superiority over placebo and conventional therapies in alleviating overall IBS symptoms and addressing small intestine bacterial overgrowth (SIBO). Despite its promising efficacy and sustained symptom relief, further research is essential to optimize long-term effectiveness and dosing regimens. Rifaximin stands as a vital treatment option for IBS due to its distinctive properties and clinical utility; yet, ongoing investigation is imperative for maximizing its therapeutic benefits.

Diagnostic strategy of irritable bowel syndrome: a low- and middle-income country perspective

Irritable bowel syndrome (IBS) is a highly prevalent gastrointestinal disorder associated with substantial impairment which considerably burdens healthcare systems worldwide. Research on IBS has largely been conducted in high-income countries posing barriers to the application of diagnostic strategies in low- and middle-income countries (LMICs) due to differences in disease characteristics, healthcare resources, and socioeconomic factors. This review discusses the diagnostic issues associated with LMICs. We present a concise overview of the relevant approaches and propose a diagnostic strategy based on the latest evidence. A positive diagnostic strategy that relies on appropriate symptom-based criteria is crucial within the diagnostic framework. A combination of complete blood count, fecal occult blood test, and complete stool test may reliably identify individuals with suspected IBS who are more likely to have organic diseases, thus justifying the necessity for a colonoscopy. Eventually, we developed a diagnostic algorithm based on a limited setting perspective that summarizes the available evidence and may be applied in LMICs.

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.

Metabolic biomarkers in irritable bowel syndrome diagnosis

Irritable bowel syndrome (IBS) is a chronic gastrointestinal (GI) disorder characterized by altered bowel habits and abdominal discomfort during defecation. It significantly impacts life quality and work productivity for those affected. Global data suggests a slightly higher prevalence in females than in males. Today, unambiguous diagnosis of IBS remains challenging due to the absence of a specific biochemical, histopathological, or radiological test. Current diagnosis relies heavily on thorough symptom evaluation. Efforts by the Rome committees have established standardized diagnostic criteria (Rome I-IV), improving consistency and clinical applicability. Recent studies in this framework, seem to have successfully employed metabolomics techniques to identify distinct metabolite profiles in breath and stool samples of IBS patients, differentiating them from healthy controls and those with other functional GI disorders, such as inflammatory bowel disease (IBD). Building on this success, researchers are investigating the presence of similar metabolites in easily accessible biofluids such as urine, potentially offering a less invasive diagnostic approach. Accordingly, this review focuses on key metabolites specifically detected in IBS patients' biological specimens, with a focus on urinary metabolites, using various methods, particularly mass spectrometry (MS)-based techniques, including gas chromatography-MS (GC-MS), liquid chromatography-tandem MS (LC-MS/MS), and capillary electrophoresis-MS (CE-MS) metabolomics assays. These findings may make provision for a new set of non-invasive biomarkers for IBS diagnosis and management.

Novel Irritable Bowel Syndrome Subgroups are Reproducible in the Global Adult Population

BACKGROUND & AIMS

Current classification systems for irritable bowel syndrome (IBS) based on bowel habit do not consider psychological impact. We validated a classification model in a UK population with confirmed IBS, using latent class analysis, incorporating psychological factors. We applied this model in the Rome Foundation Global Epidemiological Survey (RFGES), assessing impact of IBS on the individual and the health care system, and examining reproducibility.

METHODS

We applied our model to 2195 individuals in the RFGES with Rome IV-defined IBS. As described previously, we identified 7 clusters, based on gastrointestinal symptom severity and psychological burden. We assessed demographics, health care-seeking, symptom severity, and quality of life in each. We also used the RFGES to derive a new model, examining whether the broader concepts of our original model were replicated, in terms of breakdown and characteristics of identified clusters.

RESULTS

All 7 clusters were identified. Those in clusters with highest psychological burden, and particularly cluster 6 with high overall gastrointestinal symptom severity, were more often female, exhibited higher levels of health care-seeking, were more likely to have undergone previous abdominal surgeries, and had higher symptom severity and lower quality of life (P < .001 for trend for all). When deriving a new model, the best solution consisted of 10 clusters, although at least 2 seemed to be duplicates, and almost all mapped on to the previous clusters.

CONCLUSIONS

Even in the community, our original clusters derived from patients with physician-confirmed IBS identified groups of individuals with significantly higher rates of health care-seeking and abdominal surgery, more severe symptoms, and impairments in quality of life.

Celiac Disease-Related Conditions: Who to Test?

Celiac disease (CeD) is a chronic immune-mediated condition triggered by gluten consumption in genetically predisposed individuals. Approximately 1% of the general population is affected by the disorder. Disease presentation is heterogeneous and, despite growing awareness among physicians and the public, it continues to be underestimated. The most effective strategy for identifying undiagnosed CeD is proactive case finding through serologic testing in high-risk groups. We reviewed the most recent evidence on the association between CeD and more than 20 conditions. In light of this review, CeD screening is recommended in individuals with (1) autoimmune disease and accompanying symptoms suggestive of CeD; (2) diseases that may mimic CeD (eg, irritable bowel syndrome [IBS], inflammatory bowel disease [IBD], and microscopic colitis); and (3) among patients with conditions with a high CeD prevalence: first-degree relatives, idiopathic pancreatitis, unexplained liver enzyme abnormalities, autoimmune hepatitis, primary biliary cholangitis, hyposplenism or functional asplenia with severe bacterial infection, type 1 diabetes mellitus, Hashimoto's thyroiditis and Graves' disease, Sjögren's syndrome, dermatitis herpetiformis, recurrent aphthous syndrome and enamel defects, unexplained ataxia, peripheral neuropathy, delayed menarche or premature menopause, Down syndrome, Turner syndrome, Williams syndrome, chronic fatigue syndrome, IgA nephropathy, and IgA deficiency. CeD serology should be the initial step in the screening process. However, for patients with any of the aforementioned disorders who are undergoing upper endoscopy, biopsies should be performed to rule out CeD.

Clinical Presentation and Spectrum of Gluten Symptomatology in Celiac Disease

Views on the clinical presentation and symptomatology of celiac disease have evolved alongside advances in disease detection and understanding of disease pathogenesis. Although historically regarded as a pediatric illness characterized by malabsorption, it is now better viewed as an immune illness of gluten-specific T cells with systemic manifestations affecting all ages. Its broad presentation, including frequent extraintestinal manifestations and asymptomatic disease, contributes to suboptimal disease detection. Adverse symptoms greatly impact patient quality of life and can result from chronic gluten exposure in untreated disease or those poorly responsive to the gluten-free diet. They can also present as acute symptoms after episodic gluten exposure. Functional gastrointestinal disease is a common comorbidity. Biomarkers like interleukin-2 that are highly sensitive and specific for celiac disease highlight a role for gluten-specific T cells in acute gluten symptomatology. A mechanistic understanding of symptoms will inform approaches to better measure and treat them effectively.

Celiac Disease: The Importance of Studying the Duodenal Mucosa-Associated Microbiota

There is increasing evidence indicating that changes in both the composition and functionality of the intestinal microbiome are closely associated with the development of several chronic inflammatory diseases, with celiac disease (CeD) being particularly noteworthy. Thanks to the advent of culture-independent methodologies, the ability to identify and quantify the diverse microbial communities residing within the human body has been significantly improved. However, in the context of CeD, a notable challenge lies in characterizing the specific microbiota present on the mucosal surfaces of the intestine, rather than relying solely on fecal samples, which may not fully represent the relevant microbial populations. Currently, our comprehension of the composition and functional importance of mucosa-associated microbiota (MAM) in CeD remains an ongoing field of research because the limited number of available studies have reported few and sometimes contradictory results. MAM plays a crucial role in the development and progression of CeD, potentially acting as both a trigger and modulator of the immune response within the intestinal mucosa, given its proximity to the epithelial cells and direct interaction. According to this background, this review aims to consolidate the existing literature specifically focused on MAM in CeD. By elucidating the complex interplay between the host immune system and the gut microbiota, we aim to pave the way for new interventions based on novel therapeutic targets and diagnostic biomarkers for MAM in CeD.

Utility of irritable bowel syndrome subtypes and most troublesome symptom in predicting disease impact and burden

BACKGROUND

Little is known about the characteristics of individuals with irritable bowel syndrome (IBS) according to stool subtype or the most troublesome symptom reported by the individual, or whether these are useful in predicting the impact of IBS.

METHODS

We collected demographic, gastrointestinal, and psychological symptoms, healthcare usage and direct healthcare costs, impact on work and activities of daily living, and quality of life data from individuals with Rome IV-defined IBS.

KEY RESULTS

We recruited 752 people with Rome IV IBS. Individuals with IBS-D reported a poorer disease-specific quality of life than those with IBS-C or IBS-M (mean (SD) IBS-QOL 45.3 (23.0) for IBS-D, vs. 52.3 (19.9) for IBS-C, vs. 49.4 (22.0) for IBS-M, p = 0.005). Mean (SD) IBS-QOL scores were also lower amongst those who reported diarrhea (44.8 (22.3)) or urgency (44.6 (22.3)) as their most troublesome symptom, compared with those reporting abdominal pain (52.2 (22.9)), constipation (49.5 (21.8)), or abdominal bloating or distension (50.4 (21.3)). However, there were no differences in mean EQ-5D scores, IBS severity, levels of anxiety, depression, somatoform symptom-reporting, or gastrointestinal symptom-specific anxiety. Direct healthcare costs of IBS were similar across all subtypes and all most troublesome symptom groups, although some differences in work productivity and social leisure activities were detected.

CONCLUSIONS AND INFERENCES

There appears to be limited variation in the characteristics of individuals with Rome IV IBS based on both stool subtypes and most troublesome symptom reported, suggesting that gastrointestinal symptoms alone have limited ability to predict disease impact and burden.

Accuracy of the No-Biopsy Approach for the Diagnosis of Celiac Disease in Adults: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Current international guidelines recommend duodenal biopsies to confirm the diagnosis of celiac disease in adult patients. However, growing evidence suggests that immunoglobulin A (IgA) anti-tissue transglutaminase (tTg) antibody levels ≥10 times the upper limit of normal (ULN) can accurately predict celiac disease, eliminating the need for biopsy. We performed a systematic review and meta-analysis to evaluate the accuracy of the no-biopsy approach to confirm the diagnosis of celiac disease in adults.

METHODS

We systematically searched MEDLINE, EMBASE, Cochrane Library, and Web of Science from January 1998 to October 2023 for studies reporting the sensitivity and specificity of IgA-tTG ≥10×ULN against duodenal biopsies (Marsh grade ≥2) in adults with suspected celiac disease. We used a bivariate random effects model to calculate the summary estimates of sensitivity, specificity, and positive and negative likelihood ratios. The positive and negative likelihood ratios were used to calculate the positive predictive value of the no-biopsy approach across different pretest probabilities of celiac disease. The methodological quality of the included studies was evaluated using the QUADAS-2 tool. This study was registered with PROSPERO, number CRD42023398812.

RESULTS

A total of 18 studies comprising 12,103 participants from 15 countries were included. The pooled prevalence of biopsy-proven celiac disease in the included studies was 62% (95% confidence interval [CI], 40%-83%). The proportion of patients with IgA-tTG ≥10×ULN was 32% (95% CI, 24%-40%). The summary sensitivity of IgA-tTG ≥10×ULN was 51% (95% CI, 42%-60%), and the summary specificity was 100% (95% CI, 98%-100%). The area under the summary receiver operating characteristic curve was 0.83 (95% CI, 0.77 - 0.89). The positive predictive value of the no-biopsy approach to identify patients with celiac disease was 65%, 88%, 95%, and 99% if celiac disease prevalence was 1%, 4%, 10%, and 40%, respectively. Between-study heterogeneity was moderate (I2 =30.3%), and additional sensitivity analyses did not significantly alter our findings. Only 1 study had a low risk of bias across all domains.

CONCLUSION

The results of this meta-analysis suggest that selected adult patients with IgA-tTG ≥10×ULN and a moderate to high pretest probability of celiac disease could be diagnosed without undergoing invasive endoscopy and duodenal biopsy.

Celiac disease seroprevalence in subjects with dyspeptic symptoms. A study on a Mexican population

INTRODUCTION AND AIMS

Celiac disease (CD) is an autoimmune enteropathy that develops in genetically susceptible individuals. The typical gastrointestinal manifestation is diarrhea but symptoms of dyspepsia, such as epigastric pain, nausea, or satiety, can sometimes appear. Previous studies have reported that the prevalence of CD in patients with dyspepsia can be as high as 7%. The aim of the present study was to evaluate CD seroprevalence in subjects with dyspeptic symptoms and a control group in a Mexican population.

MATERIAL AND METHODS

A case-control study was conducted on blood donors that answered the PAGI-SYM questionnaire for dyspepsia and in whom IgA antibodies to tissue transglutaminase 2 (IgA anti-tTG2) and IgG antibodies to deamidated gliadin peptide (IgG anti-DGP) were determined. CD seroprevalence in subjects with dyspeptic symptoms and in asymptomatic subjects was compared.

RESULTS

A total of 427 subjects (76.3% men), with a mean patient age of 34 years (range of 18-65 years) were included. Of those participants, 87 (20.3%) had symptoms of dyspepsia (group A) and 340 (79.6%) were asymptomatic (group B). Antibodies were positive in one (1.15%) of the group A subjects (1/87, 95% CI 0.2-6 %), whereas they were positive in 4 (1.18%) of the group B subjects (4/340, 95% CI 0.4-2.9%, p = 0.59).

CONCLUSIONS

CD seroprevalence in the study population with dyspeptic symptoms (1%) was not different from that of the control population. Thus, CD screening in Mexican patients with dyspepsia is not justified.

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.

Journal of Clinical Gastroenterology Lectureship Dubai 2022 : Management of Irritable Bowel Syndrome With Diarrhea

Irritable bowel syndrome (IBS) with diarrhea (IBS-D) affects ~1% of the general population and is characterized by abdominal pain associated with diarrhea. IBS-D symptoms significantly impact the quality of life of patients. Major uncertainties remain regarding the optimal management of these patients. Several therapies have been investigated over the years for the treatment of IBS-D. In the initial management, commonly prescribed approaches with an effect on global IBS symptoms include a low Fermentable Oligo-, Di-, Mono-Saccharides and Polyols diet and probiotics, while antispasmodics are used for targeting abdominal pain and loperamide for diarrhea only. Additional therapeutic options for the relief of global IBS symptoms include rifaximin, 5-HT 3 antagonists, gut-directed psychological therapies, and eluxadoline, while tricyclic antidepressants can target abdominal pain and bile acid sequestrants diarrhea. Promising evidence exists for the use of mesalazine and fecal microbiota transplantation in IBS-D, although further evidence is needed for definitive conclusions regarding their efficacy.

Novel Symptom Subgroups in Individuals With Irritable Bowel Syndrome Predict Disease Impact and Burden

BACKGROUND & AIMS

Current classification systems based on bowel habit fail to capture the multidimensional nature of irritable bowel syndrome (IBS). We previously derived and validated a classification system, using latent class analysis, incorporating factors beyond bowel habit. We applied this in another cohort of people with IBS to assess its ability to capture the impact of IBS on the individual, the health care system, and society.

METHODS

We collected demographic, symptom, and psychological health data from adults in the community self-identifying as having IBS, and meeting Rome IV criteria. We applied our latent class analysis model to identify the 7 subgroups (clusters) described previously, based on overall gastrointestinal symptom severity and psychological burden. We assessed quality of life, health care costs (£1 = $1.20), employment status, annual income, work productivity, and ability to perform work duties in each cluster.

RESULTS

Of 1278 responders, 752 (58.8%) met Rome IV criteria. The 7-cluster model fit the data well. The patients in the 4 clusters with the highest psychological burden, and particularly those in cluster 6 with high overall gastrointestinal symptom severity and high psychological burden, showed lower educational levels, higher gastrointestinal symptom-specific anxiety, were more likely to have consulted a gastroenterologist, and used more drugs for IBS. IBS-related and generic quality of life were impaired significantly in these 4 clusters and significantly fewer individuals reported earning ≥£30,000 per year. Productivity and the ability to work, manage at home, engage in social and private leisure activities, and maintain close relationships all were impacted significantly, and IBS-related health care costs over the previous 12 months were highest in these 4 clusters. In those in cluster 6, costs were more than £1000 per person per year.

CONCLUSIONS

Our clusters identify groups of individuals with significant impairments in quality of life, earning potential, and ability to work and function socially, who are high utilizers of health care.

A Diagnosis of Irritable Bowel Syndrome Using Rome IV Criteria and Limited Investigations is Durable in Secondary Care

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is a positive diagnosis, made using symptom-based criteria and limited, judicious, investigation. However, this may lead to uncertainty on the part of clinicians regarding potential for a missed diagnosis of organic gastrointestinal disease. Few studies have examined durability of a diagnosis of IBS, and none have used the current gold standard to diagnose IBS, the Rome IV criteria.

METHODS

We collected complete symptom data from 373 well-characterized adults meeting Rome IV criteria for IBS referred to a single UK clinic between September 2016 and March 2020. All patients underwent relatively standardized work-up to exclude relevant organic disease before diagnosis. We followed these individuals up to December 2022, assessing rates of rereferral, reinvestigation, and missed organic gastrointestinal disease.

RESULTS

During a mean follow-up of 4.2 years per patient (total follow-up in all patients, 1565 years), 62 (16.6%) patients were rereferred. Of these, 35 (56.5%) were rereferred for IBS and 27 (43.5%) for other gastrointestinal symptoms. Among the 35 rereferred with IBS this was caused by a change in symptoms in only 5 (14.3%). Reinvestigation was undertaken in 21 (60.0%) of 35 rereferred with IBS and 22 (81.5%) of 27 rereferred with other symptoms (P = .12). Only 4 (9.3% of those reinvestigated and 1.1% of the entire cohort) new cases of relevant organic disease, which may have been responsible for IBS symptoms at baseline, were identified (1 case of chronic calcific pancreatitis among those rereferred with IBS and 1 case each of inflammatory bowel disease-unclassified, moderate bile acid diarrhea, and small bowel obstruction among those rereferred with other gastrointestinal symptoms).

CONCLUSIONS

Despite rereferral for gastrointestinal symptoms among 1 in 6 patients overall, with almost 10% rereferred with ongoing IBS symptoms, and substantial reinvestigation rates, missed organic gastrointestinal disease occurred in only 1%. A diagnosis of Rome IV IBS after limited investigation is safe and durable.

Prevalence of Coagulopathy in Patients with Celiac Disease: A Single-Center Retrospective Case-Control Study

Introduction: Despite being one of the most frequent chronic digestive diseases worldwide, with a prevalence of 1%, celiac disease (CD) remains severely underdiagnosed. Among the instruments used to improve its diagnostic rate, hematologic parameters have been proposed as screening tests to select patients with an increased probability of having CD. Assessment of coagulation is included in routine check-ups, and CD has been reported to be associated with coagulopathy. We aimed to assess if subtle changes in coagulation tests could be used in clinical practice to prompt testing for CD. Methods: We retrospectively recruited all patients with clinical suspicion for CD during a study period of 7 years (between 2015 and 2022), who were tested using IgA tissue transglutaminase (tTG) serology and serum total IgA (IgG tTG in case of IgA deficiency) and who underwent upper gastrointestinal endoscopy with multiple biopsy sampling of the duodenal bulb and distal duodenum. We stratified patients into three groups: newly diagnosed CD, gluten-free diet-treated CD, and non-CD controls. Results: Altogether, there were 133 CD patients (71 newly diagnosed, 62 GFD-treated) and 57 non-CD controls. Mean age and gender distribution were similar among the three groups: 43.3 years for newly diagnosed CD, 41.6 years for non-CD controls, and 44 years for GFD-treated CD patients, with a male gender distribution of 21.1%, 28%, and 24.1%, respectively. Among the included newly diagnosed CD patients, 14% had a prolonged INR. The mean INR was slightly higher in newly diagnosed CD patients, compared to GFD-treated CD patients and non-CD controls: 1.12 ± 0.30, 1.02 ± 0.83, and 1.00 ± 0.08, respectively (p = 0.009). Consequently, prothrombin activity was slightly lower in newly diagnosed CD patients, compared to GFD-treated CD and non-CD controls: 94.9 ± 19.3%, 102.3 ± 12.8%, and 101.9 ± 15.15, respectively. Interestingly, after GFD, the mean INR and prothrombin activity of CD individuals reached a value similar to that of non-CD controls. Conclusions: Subtle changes in INR, defined as a value within the normal range, but closer to the upper limit, could be an indicator of probability for CD.

The Occurrence of Gluten-Related Antibodies, Sensitization to Selected Food Allergens, and Antibodies against Intrinsic Factor in Adult Patients with Diarrhea-Predominant Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. Due to the possible overlap of IBS clinical symptoms with gluten-related diseases, food allergies, and autoimmune gastritis (AIG), the aim of this study was to present the frequency of anti-tissue transglutaminase 2 (TTG2) autoantibodies, anti-deamidated gluten peptide (DGP) antibodies, specific immunoglobulin E antibodies (sIgE) to selected food allergens, and anti-intrinsic factor (IF) autoantibodies in adult patients with diarrhea-predominant IBS (IBS-D). The study involved 244 patients (170 women) aged 18-75 years. The antibodies were measured with the use of multiparametric immunoassays. Elevated antibody concentrations, irrespective of the class of tested antibody, occurred in 44 patients (17.6%), including 11 patients (4.5%) with positive DGP antibodies, four patients (1.6%) with TTG2 autoantibodies, six patients (2.5%) with IF autoantibodies, and 31 patients (12.7%) with sIgE to food allergens. Sensitization to gluten, proteins from cow's milk, and bovine serum albumin was found in 2.1%, 5.3%, and 9.0% of patients, respectively. Our study showed a high percentage of positive results for the tested antibodies in the IBD-D patients, which indicates the need to perform serological tests for CD, food allergies, and AIG in this group of patients.

Loose ends in the differential diagnosis of IBS-like symptoms

Two thirds of the patients we believed to have IBS in the 1970's have since been possible to diagnose with treatable conditions like bile acid diarrhea, inflammatory bowel disease, microscopic colitis, celiac disease, disaccharide malabsorption, exocrine pancreatic insufficiency, or rare genetic variants. Despite advances in diagnostic techniques a substantial proportion of patients continue suffering from IBS-like symptoms that cannot be explained by current knowledge. Although it is likely that further research will reveal small but important subgroups of patients with treatable mechanisms for IBS-like symptoms, we propose that only two large groups remain for being addressed in the clinic: those with connective tissue disorders such as Ehlers-Danlos syndrome or hypermobility spectrum disorders and those with autism spectrum disorders. Patients with connective tissue disorders exhibit identifiable disturbances of gut motor function and possibly increased gut permeability as underlying mechanisms for IBS-like symptoms. Autism spectrum disorders pose a much more difficult problem in the clinic. Disturbances of perception combined with anxiety and excessive worry about signals from the gut can lead to an endless but futile search for something being wrong. The search can involve large numbers of care givers, no one understanding the patient's suffering. Others may try to change their diet to lessen symptoms, only to find that almost all foods may cause worrying perceptions from the gut. Early recognition of autism spectrum disorders is essential for finding better ways to help patients with gastrointestinal and, as is often the case, extraintestinal symptoms.

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.

Updates in the diagnosis and management of coeliac disease

Coeliac disease is a common autoimmune disorder induced by ingesting gluten, the protein component of wheat, barley, and rye. It is estimated that one-in-hundred people worldwide have coeliac disease, of whom the majority remain undiagnosed. Coeliac disease is characterized by a wide range of gastrointestinal and extraintestinal symptoms but can also present asymptomatically. Diagnosing coeliac disease depends on the concordance of clinical, serological and histopathological data. However, the diagnosis can be challenging and frequently overlooked. Undiagnosed coeliac disease is associated with an increased risk of complications and detrimental effects on quality of life. Early diagnosis and treatment of coeliac disease are necessary to reduce the risk of long-term complications.

Italian guidelines for the management of irritable bowel syndrome: Joint Consensus from the Italian Societies of: Gastroenterology and Endoscopy (SIGE), Neurogastroenterology and Motility (SINGEM), Hospital Gastroenterologists and Endoscopists (AIGO), Digestive Endoscopy (SIED), General Medicine (SIMG), Gastroenterology, Hepatology and Pediatric Nutrition (SIGENP) and Pediatrics (SIP)

The irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction. IBS is still associated with areas of uncertainties, especially regarding the optimal diagnostic work-up and the more appropriate management. Experts from 7 Italian Societies conducted a Delphi consensus with literature summary and voting process on 27 statements. Recommendations and quality of evidence were evaluated using the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus was defined as >80% agreement and reached for all statements. In terms of diagnosis, the consensus supports a positive diagnostic strategy with a symptom-based approach, including the psychological comorbidities assessment and the exclusion of alarm symptoms, together with the digital rectal examination, full blood count, C-reactive protein, serology for coeliac disease, and fecal calprotectin assessment. Colonoscopy should be recommended in patients with alarm features. Regarding treatment, the consensus strongly supports a dietary approach for patients with IBS, the use of soluble fiber, secretagogues, tricyclic antidepressants, psychologically directed therapies and, only in specific IBS subtypes, rifaximin. A conditional recommendation was achieved for probiotics, polyethylene glycol, antispasmodics, selective serotonin reuptake inhibitors and, only in specific IBS subtypes, 5-HT3 antagonists, 5-HT4 agonists, bile acid sequestrants.

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.

Latent class analysis does not support the existence of Rome IV functional bowel disorders as discrete entities

BACKGROUND

Previously, we used latent class analysis (LCA) to identify novel subgroups in people with irritable bowel syndrome (IBS). There are four other functional bowel disorders that, although characterized as discrete disorders, overlap considerably with, and fluctuate to, IBS. These might instead be conceptualized as a milder form of IBS. We explored this hypothesis using LCA in a cohort of people with non-IBS functional bowel disorders.

METHODS

We collected demographic, symptom, and psychological health data from 1375 adults in the community who self-identified as having IBS and identified individuals meeting Rome IV criteria for any non-IBS functional bowel disorder. We performed LCA to identify specific subgroups (clusters). We followed participants up at 12 months to reassess gastrointestinal and psychological heath and also gather data about healthcare utilization and impact of symptoms.

KEY RESULTS

811 people met Rome IV criteria for IBS and 558 Rome IV criteria for another functional bowel disorder (76 (5.5%) functional constipation; 198 (14.5%) functional diarrhea; 129 (9.5%) functional abdominal bloating or distension; and 155 (11.4%) unspecified functional bowel disorder). LCA in these 558 people identified five clusters defined by a combination of gastrointestinal symptoms and the extent of psychological co-morbidity. However, correlation between these clusters and the Rome IV functional bowel disorder diagnoses was poor and 75% of people were classified as having mild IBS using our previous IBS-derived model. By 12 months, one-third of people had fluctuated and met criteria for IBS. Clusters with high psychological burden had a poorer prognosis, with higher rates of medical consultation, medication use, and greater impact of symptoms on daily life.

CONCLUSIONS AND INFERENCES

The functional bowel disorders may be better characterized as a spectrum of IBS rather than separate disorders. Adopting this pragmatic stance may help to simply diagnosis, treatment, and recruitment of patients to research trials.

Guidelines of the Italian societies of gastroenterology on the diagnosis and management of coeliac disease and dermatitis herpetiformis

INTRODUCTION

Coeliac disease and dermatitis herpetiformis are immune-mediated diseases triggered by the consumption of gluten in genetically predisposed individuals. These guidelines were developed to provide general practitioners, paediatricians, gastroenterologists, and other clinicians with an overview on the diagnosis, management and follow-up of coeliac patients and those with dermatitis herpetiformis.

METHODS

Guidelines were developed by the Italian Societies of Gastroenterology. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists and a paediatrician with expertise in this field.

RESULTS

These guidelines provide a practical guidance for the diagnosis, management and follow-up of coeliac patients and dermatitis herpetiformis in children and adults, both in primary care and in specialist settings. We developed four sections on diagnosis, gluten-free diet, follow-up and risk of complications in adults, one section focused on diagnosis and follow-up in children and one on the diagnosis and management of dermatitis herpetiformis.

CONCLUSIONS

These guidelines may support clinicians to improve the diagnosis and management of patients with coeliac disease.

Defining the optimum strategy for identifying adults and children with coeliac disease: systematic review and economic modelling

BACKGROUND

Coeliac disease is an autoimmune disorder triggered by ingesting gluten. It affects approximately 1% of the UK population, but only one in three people is thought to have a diagnosis. Untreated coeliac disease may lead to malnutrition, anaemia, osteoporosis and lymphoma.

OBJECTIVES

The objectives were to define at-risk groups and determine the cost-effectiveness of active case-finding strategies in primary care.

DESIGN

(1) Systematic review of the accuracy of potential diagnostic indicators for coeliac disease. (2) Routine data analysis to develop prediction models for identification of people who may benefit from testing for coeliac disease. (3) Systematic review of the accuracy of diagnostic tests for coeliac disease. (4) Systematic review of the accuracy of genetic tests for coeliac disease (literature search conducted in April 2021). (5) Online survey to identify diagnostic thresholds for testing, starting treatment and referral for biopsy. (6) Economic modelling to identify the cost-effectiveness of different active case-finding strategies, informed by the findings from previous objectives.

DATA SOURCES

For the first systematic review, the following databases were searched from 1997 to April 2021: MEDLINE® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), Cochrane Library, Web of Science™ (Clarivate™, Philadelphia, PA, USA), the World Health Organization International Clinical Trials Registry Platform ( WHO ICTRP ) and the National Institutes of Health Clinical Trials database. For the second systematic review, the following databases were searched from January 1990 to August 2020: MEDLINE, Embase, Cochrane Library, Web of Science, Kleijnen Systematic Reviews ( KSR ) Evidence, WHO ICTRP and the National Institutes of Health Clinical Trials database. For prediction model development, Clinical Practice Research Datalink GOLD, Clinical Practice Research Datalink Aurum and a subcohort of the Avon Longitudinal Study of Parents and Children were used; for estimates for the economic models, Clinical Practice Research Datalink Aurum was used.

REVIEW METHODS

For review 1, cohort and case-control studies reporting on a diagnostic indicator in a population with and a population without coeliac disease were eligible. For review 2, diagnostic cohort studies including patients presenting with coeliac disease symptoms who were tested with serological tests for coeliac disease and underwent a duodenal biopsy as reference standard were eligible. In both reviews, risk of bias was assessed using the quality assessment of diagnostic accuracy studies 2 tool. Bivariate random-effects meta-analyses were fitted, in which binomial likelihoods for the numbers of true positives and true negatives were assumed.

RESULTS

People with dermatitis herpetiformis, a family history of coeliac disease, migraine, anaemia, type 1 diabetes, osteoporosis or chronic liver disease are 1.5-2 times more likely than the general population to have coeliac disease; individual gastrointestinal symptoms were not useful for identifying coeliac disease. For children, women and men, prediction models included 24, 24 and 21 indicators of coeliac disease, respectively. The models showed good discrimination between patients with and patients without coeliac disease, but performed less well when externally validated. Serological tests were found to have good diagnostic accuracy for coeliac disease. Immunoglobulin A tissue transglutaminase had the highest sensitivity and endomysial antibody the highest specificity. There was little improvement when tests were used in combination. Survey respondents (n = 472) wanted to be 66% certain of the diagnosis from a blood test before starting a gluten-free diet if symptomatic, and 90% certain if asymptomatic. Cost-effectiveness analyses found that, among adults, and using serological testing alone, immunoglobulin A tissue transglutaminase was most cost-effective at a 1% pre-test probability (equivalent to population screening). Strategies using immunoglobulin A endomysial antibody plus human leucocyte antigen or human leucocyte antigen plus immunoglobulin A tissue transglutaminase with any pre-test probability had similar cost-effectiveness results, which were also similar to the cost-effectiveness results of immunoglobulin A tissue transglutaminase at a 1% pre-test probability. The most practical alternative for implementation within the NHS is likely to be a combination of human leucocyte antigen and immunoglobulin A tissue transglutaminase testing among those with a pre-test probability above 1.5%. Among children, the most cost-effective strategy was a 10% pre-test probability with human leucocyte antigen plus immunoglobulin A tissue transglutaminase, but there was uncertainty around the most cost-effective pre-test probability. There was substantial uncertainty in economic model results, which means that there would be great value in conducting further research.

LIMITATIONS

The interpretation of meta-analyses was limited by the substantial heterogeneity between the included studies, and most included studies were judged to be at high risk of bias. The main limitations of the prediction models were that we were restricted to diagnostic indicators that were recorded by general practitioners and that, because coeliac disease is underdiagnosed, it is also under-reported in health-care data. The cost-effectiveness model is a simplification of coeliac disease and modelled an average cohort rather than individuals. Evidence was weak on the probability of routine coeliac disease diagnosis, the accuracy of serological and genetic tests and the utility of a gluten-free diet.

CONCLUSIONS

Population screening with immunoglobulin A tissue transglutaminase (1% pre-test probability) and of immunoglobulin A endomysial antibody followed by human leucocyte antigen testing or human leucocyte antigen testing followed by immunoglobulin A tissue transglutaminase with any pre-test probability appear to have similar cost-effectiveness results. As decisions to implement population screening cannot be made based on our economic analysis alone, and given the practical challenges of identifying patients with higher pre-test probabilities, we recommend that human leucocyte antigen combined with immunoglobulin A tissue transglutaminase testing should be considered for adults with at least a 1.5% pre-test probability of coeliac disease, equivalent to having at least one predictor. A more targeted strategy of 10% pre-test probability is recommended for children (e.g. children with anaemia).

FUTURE WORK

Future work should consider whether or not population-based screening for coeliac disease could meet the UK National Screening Committee criteria and whether or not it necessitates a long-term randomised controlled trial of screening strategies. Large prospective cohort studies in which all participants receive accurate tests for coeliac disease are needed.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019115506 and CRD42020170766.

FUNDING

This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 44. See the NIHR Journals Library website for further project information.

British Society of Gastroenterology guidelines on the management of functional dyspepsia

Functional dyspepsia (FD) is a common disorder of gut-brain interaction, affecting approximately 7% of individuals in the community, with most patients managed in primary care. The last British Society of Gastroenterology (BSG) guideline for the management of dyspepsia was published in 1996. In the interim, substantial advances have been made in understanding the complex pathophysiology of FD, and there has been a considerable amount of new evidence published concerning its diagnosis and classification, with the advent of the Rome IV criteria, and management. The primary aim of this guideline, commissioned by the BSG, is to review and summarise the current evidence to inform and guide clinical practice, by providing a practical framework for evidence-based diagnosis and treatment of patients. The approach to investigating the patient presenting with dyspepsia is discussed, and efficacy of drugs in FD summarised based on evidence derived from a comprehensive search of the medical literature, which was used to inform an update of a series of pairwise and network meta-analyses. Specific recommendations have been made according to the Grading of Recommendations Assessment, Development and Evaluation system. These provide both the strength of the recommendations and the overall quality of evidence. Finally, in this guideline, we consider novel treatments that are in development, as well as highlighting areas of unmet need and priorities for future research.

Who to screen and how to screen for celiac disease

Celiac disease (CeD) is a chronic gluten-induced enteropathy with plethoric manifestations. The typical manifestations of CeD such as chronic diarrhea and malabsorption are widely recognized, however, many patients have atypical manifestations like iron deficiency anemia, idiopathic short stature, hypertransaminesemia or infertility, etc. These patients often present to the primary care physicians and/or non-gastrointestinal specialties. However, due to a lack of awareness among the healthcare professionals about the various atypical manifestations, many patients are not screened for CeD. In this review, we have summarized the available literature about the prevalence of CeD in various gastrointestinal (chronic diarrhea) and non-gastrointestinal conditions (iron deficiency anemia, short stature, cryptogenic hypertransaminesemia, cryptogenic cirrhosis or idiopathic ataxia etc.) where the diagnosis of CeD should be con-sidered. In addition, we also discuss special scenarios where screening for CeD should be considered even in absence of symptoms such as patients with type 1 diabetes, Down’s syndrome, and first-degree relatives of patients with CeD. Further, we discuss the diagnostic performance and limitations of various screening tests for CeD such as IgA anti-tissue transglutaminase antibodies, anti-endomysial antibodies and anti-deamidated gliadin antibodies. Based on the current recommendations, we propose a diagnostic algorithm for patients with suspected CeD.

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.

Clinical presentation, biochemical profile, and HLA haplotype frequency of celiac disease among adults in Northwest China

OBJECTIVE

To evaluate the clinical characteristics, biochemical parameters and the distribution of HLA-DQ genotypes among adult patients with celiac disease (CD) in Northwest China.

METHODS

This cross-sectional study retrospectively collected clinical, biochemical, and HLA-DQ genotype of patients with CD from a tertiary hospital in Xinjiang Uygur Autonomous Region, China between March 2016 and December 2021. Small intestinal biopsy and serum-specific antibodies were used to diagnose CD.

RESULTS

Of the 102 CD patients, 63.7% were women (female: male = 1.76:1), and the mean age was 47.3 ± 14.7 years at diagnosis. Common gastrointestinal symptoms included abdominal pain (50.0%), diarrhea (39.2%), and abdominal distension (24.5%). While common extraintestinal manifestations were anemia (48.0%), osteopenia or osteoporosis (36.3%), and fatigue (35.3%). Approximately 34.3% of patients with CD had comorbidities, with the most common being thyroid diseases (18.6%). Biochemical profiles showed lower hemoglobin, higher platelet count, and 25-hydroxyvitamin D (25[OH]D) deficiency. HLA-DQ2/DQ8 was detected among all 53 patients who underwent genotype testing; the frequency of the HLA-DQ2.5, DQ2.2, and DQ8 haplotypes was 71.7%, 24.5%, and 3.8%, respectively.

CONCLUSIONS

CD was more common among women. Clinical manifestations include primarily gastrointestinal symptoms, but extraintestinal manifestations were not uncommon. Lower hemoglobin level, higher platelet count, and 25[OH]D deficiency are the main biochemical manifestations. The HLA-DQ2.5 and DQ2.2 haplotypes are the most common genotypes in CD.

Functional bowel disorders with diarrhoea: Clinical guidelines of the United European Gastroenterology and European Society for Neurogastroenterology and Motility

Irritable bowel syndrome with diarrhoea (IBS‐D) and functional diarrhoea (FDr) are the two major functional bowel disorders characterized by diarrhoea. In spite of their high prevalence, IBS‐D and FDr are associated with major uncertainties, especially regarding their optimal diagnostic work‐up and management. A Delphi consensus was performed with experts from 10 European countries who conducted a literature summary and voting process on 31 statements. Quality of evidence was evaluated using the grading of recommendations, assessment, development, and evaluation criteria. Consensus (defined as >80% agreement) was reached for all the statements. The panel agreed with the potential overlapping of IBS‐D and FDr. In terms of diagnosis, the consensus supports a symptom‐based approach also with the exclusion of alarm symptoms, recommending the evaluation of full blood count, C‐reactive protein, serology for coeliac disease, and faecal calprotectin, and consideration of diagnosing bile acid diarrhoea. Colonoscopy with random biopsies in both the right and left colon is recommended in patients older than 50 years and in presence of alarm features. Regarding treatment, a strong consensus was achieved for the use of a diet low fermentable oligo‐, di‐, monosaccharides and polyols, gut‐directed psychological therapies, rifaximin, loperamide, and eluxadoline. A weak or conditional recommendation was achieved for antispasmodics, probiotics, tryciclic antidepressants, bile acid sequestrants, 5‐hydroxytryptamine‐3 antagonists (i.e. alosetron, ondansetron, or ramosetron). A multinational group of European experts summarized the current state of consensus on the definition, diagnosis, and management of IBS‐D and FDr.

Improving the diagnostic approach to celiac disease: Experience from a regional network

BACKGROUND

Celiac disease (CD) is still underestimated. To close this diagnostic gap, the Health Sicilian Authorities have constituted the "Sicilian Network for CD".

AIMS

A) To verify the quality of the current diagnostic approach using the data sheet of the Network. B) To evaluate the clinical, serologic and histologic data of new diagnoses in the context of the Network METHODS: We retrospectively evaluated the data collection forms of 369 patients with CD from three Centers within the Sicilian Network. All the Centers used a standard data collection form.

RESULTS

A non-classical CD presentation was more frequent than the classical one, anemia being the most frequent symptom (50%). An IBS-like presentation was found in one third of the cases. A diagnostic delay of about 9 years following the onset of symptoms was observed. Almost half of the patients had not undergone multiple duodenal biopsies; unrecommended CD serology assays were prescribed in 59.9% of the cases.

CONCLUSIONS

The regional data sheets allowed an assessment of the diagnostic delay. We recorded a frequent use of unrecommended tests prescribed before referring patients to the regional Centers. Updating the education of physicians regarding CD is necessary to avoid unwarranted health expenditure.

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.

Epidemiological, clinical, and histological presentation of celiac disease in Northwest China

BACKGROUND

Research on celiac disease (CD) in northwest China is still in its infancy. At present, large-sample data on the epidemiological, clinical, and pathological characteristics of CD are limited.

AIM

To investigate the epidemiological, clinical, and pathological characteristics of CD in northwest China.

METHODS

The clinical data of 2884 patients with gastrointestinal (GI) symptoms were retrospectively analyzed. Total immunoglobulin A (IgA) and anti-tissue transglutaminase (tTG) IgA levels were examined in all patients. Gastroscopy and colonoscopy were performed in patients with positive anti-tTG IgA and deficient total IgA levels. Atrophy of the duodenal and ileal villi was examined and histopathological examinations were performed. The modified Marsh–Oberhuber classification system was used to grade villous atrophy in the duodenum or distal ileum. The patients’ Helicobacter pylori (H. pylori) infection status was compared in terms of clinical presentation and Marsh grade. Statistical analyses were performed using the t-test or chi-square test.

RESULTS

Among the 2884 patients, 73 were positive for serum anti-tTG IgA, and 50 were diagnosed with CD. The CD detection rate was significantly higher in Kazakhs (4.39%) than in Uyghurs (2.19%), Huis (0.71%), and Hans (0.55%). The main symptoms of CD were chronic diarrhea, anorexia, anemia, fatigue, weight loss, sleep disorders, osteopenia, and osteoporosis. The body mass index of patients with CD was significantly lower than that of patients without CD. A total of 69 patients with positive serum anti-tTG IgA and two patients with deficient total IgA levels underwent GI endoscopy. Endoscopy revealed crypt hyperplasia and/or duodenal villous atrophy, mainly manifested as nodular mucosal atrophy, grooves, and fissures. The difference in H. pylori infection rates was not statistically significant between CD and non-CD patients but was significantly different among CD patients with different Marsh grades.

CONCLUSION

Among the patients with GI symptoms in northwestern China, the prevalence of CD was more in the Uyghur and Kazakh populations. H. pylori infection may be associated with CD severity.

Irritable bowel syndrome

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The seroprevalence of celiac disease in patients with symptoms of irritable bowel syndrome: A cross-sectional study in north of Iran

BACKGROUND

Celiac disease (CD) is a common cause of malabsorption that is definitively diagnosed by abnormal bowel biopsy, symptoms and histologic changes to gluten free diet. The symptoms of irritable bowel syndrome (IBS) are common in our community as the majority of people in Guilan, north of Iran, consume rice daily. Also, a number of celiac patients are unknown, and IBS are mistakenly diagnosed.

OBJECTIVE

This study aimed to evaluate the prevalence of CD among IBS patients.

METHODS

A total of 475 consecutive patients with IBS, confirmed by Rome IV, underwent celiac serological tests antitissue transglutaminase antibodies (IgA-tTG, IgG-tTG) after obtaining a written consent form. In case of positive serological tests, biopsy was performed from small intestine after endoscopyRESULTS: Thirty-one (6.53%, 95% CI: 4.55-9.22) patients were positive for celiac serology. Based on Marsh-Oberhuber criteria, out of 9 patients with positive pathology 77.78% (95% CI: 40.19-96.05) had marsh IIIc. In IBS patients cramp (0.009) and stomach fullness (0.021) were two statistically significant IBS symptoms.

CONCLUSIONS

We suggest physicians to consider celiac examinations for all patients with IBS symptoms, even for patients with no obvious celiac symptoms.

Commonly used biomarkers do not contribute to diagnosing irritable bowel syndrome

OBJECTIVE

The aim of this article was to examine the costs and effectiveness of standardized blood and fecal investigations in patients fulfilling the Rome criteria for irritable bowel syndrome (IBS).

METHODS

We conducted a real-life cohort study in patients fulfilling the Rome III criteria for IBS without red flag signs or symptoms, in a center of excellence for IBS patients from 1 January 2015 till 1 January 2019. Standardized blood and fecal investigations [hemoglobin (Hb), thyroid-stimulating hormone (TSH), coeliac serology, and fecal calprotectin (FCP)] were performed during the first consultation. Patients were followed for at least 1 year. Primary outcome was the probability of another diagnosis than IBS with subsequent overall costs.

RESULTS

A total of 218 patients were included. In approximately 200 patients blood and fecal investigations were performed and 47 patients underwent a colonoscopy. Two-hundred ten patients were diagnosed with IBS, 5 with inflammatory bowel disease (IBD), 1 with nonspecific acute ileitis, 1 with hyperthyroidism, and 1 with coeliac disease. The number needed to diagnose all included laboratory tests was 34, and for the individual test: TSH 197, coeliac serology 199, and FCP 50. The total costs were approximately €4900 to diagnose one patient with another diagnosis than IBS.

CONCLUSION

In our real-life cohort of adult patients under the age of 50 years fulfilling the Rome criteria for IBS without red flag symptoms, standardized blood, and fecal investigations have a very low diagnostic yield accompanied by high additional costs. Colonoscopy is not indicated in patients with Rome III positive IBS and normal FCP.

Natural History and Disease Impact of Rome IV Vs Rome III Irritable Bowel Syndrome: A Longitudinal Follow-Up Study

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is a chronic functional bowel disorder diagnosed using the Rome criteria, which have evolved since their original description 30 years ago. Little is known about the effects on the natural history of IBS of moving to the latest iteration, Rome IV, from the previous Rome III criteria. We conducted a 12-month longitudinal follow-up study to examine this.

METHODS

We collected complete demographic, symptom, mood, and psychological health data at baseline from 1097 adults who self-identified as having IBS and met either Rome IV or Rome III criteria. At 12 months, we collected data regarding IBS symptom severity and impact, consultation behavior, treatments commenced, and psychological health. We examined whether subsequent disease behavior in Rome IV- or Rome III-defined IBS differed.

RESULTS

At 12 months, 638 (58.2%) of the 1097 participants were followed up successfully. Of these, 452 met Rome IV criteria and 186 met Rome III criteria at baseline. During the 12-month study period, individuals with Rome IV IBS were significantly more likely to have seen a primary care physician (44.7% vs 28.5%; P < .001) or a gastroenterologist (26.3% vs 12.4%; P < .001) for their IBS symptoms, were significantly more likely to have commenced a new treatment (73.0% vs 60.2%; P = .001), and cycled through significantly more treatments (P = .007), for their IBS compared with those with Rome III IBS. At follow-up evaluation, individuals with Rome IV IBS had more severe symptoms, which had a significantly greater impact on activities of daily living, were more likely to report continuous abdominal pain, and a higher proportion showed poor psychological health, compared with those with Rome III IBS (P < .001 for all analyses).

CONCLUSIONS

The natural history of IBS defined according to Rome IV criteria is more severe than that of Rome III-defined IBS. This has important implications for future treatment trials in IBS.

Celiac Disease Revisited

Celiac disease (CD) is a systemic disease triggered by gluten ingestion in genetically predisposed individuals. It manifests primarily as an autoimmune enteropathy associated with specific circulating autoantibodies and a human leukocyte antigen haplotype (HLA-DQ2 or HLA-DQ8). It afflicts roughly 1% of the population, though the majority of patients remain undiagnosed. Diarrhea and malabsorption are classic manifestations of CD; however, both children and adults can be paucisymptomatic and present extraintestinal manifestations such as anemia, osteoporosis, and abnormal liver tests. CD screening is not recommended for the general population, and it should be focused on high-risk groups. CD diagnosis is challenging and relies on serological tests, duodenal histology, and genetic testing. Particularly difficult presentations to manage are seronegative patients, seropositive patients without villus atrophy, and patients who have started a gluten-free diet before the diagnostic workup. The only proven treatment is a lifelong gluten-free diet. We present an in-depth review on the physiopathology and management of CD, with a particular emphasis on diagnostic challenges.

A systematic review and meta-analysis on the prevalence of non-malignant, organic gastrointestinal disorders misdiagnosed as irritable bowel syndrome

Treatable gastrointestinal disorders in patients with symptoms typical for irritable bowel syndrome (IBS) may be overlooked. The prevalence of five gastrointestinal conditions-bile acid diarrhoea (BAD), carbohydrate malabsorption (CM), microscopic colitis (MC), pancreatic exocrine insufficiency (PEI) and small intestinal bacterial overgrowth (SIBO) was systematically assessed from studies including consecutive patients meeting diagnostic criteria for IBS. 4 databases were searched from 1978 to 2020. Studies were included if they evaluated the prevalence of these conditions in secondary healthcare setting. Estimated pooled rates were calculated and statistical heterogeneity between studies was evaluated using Q and I2 statistics. Seven studies (n = 597) estimated the pooled prevalence for BAD as 41% (95% CI 29-54). 17 studies (n = 5068) estimated that of MC as 3% (95% CI 2-4%). Two studies (n = 478) suggested a rate of 4.6% (range: 1.8-6.1%) for PEI. Using breath testing, 26 studies (n = 6700) and 13 studies (n = 3415) estimated the prevalence of lactose and fructose malabsorption as 54% (95% CI 44-64%) and 43% (95% CI 23-62%); 36 studies (n = 4630) and 22 studies (n = 2149) estimated that of SIBO as 49% (95% CI 40-57%) with lactulose and 19% (95% CI 13-27%) with glucose. Rates of all conditions were significantly higher than in healthy controls. A significant proportion of patients presenting to secondary care with IBS have an organic condition which may account for their symptoms. Failure to exclude such conditions will deny patients effective treatment.

Diagnostic Yield of Colonoscopy in Patients With Symptoms Compatible With Rome IV Functional Bowel Disorders

BACKGROUND & AIMS

There is little data on the diagnostic yield of colonoscopy in patients with symptoms compatible with functional bowel disorders (FBDs). Previous studies have only focused on diagnostic outcomes of colonoscopy in those with suspected irritable bowel syndrome using historic Rome I-III criteria, whilst having partially assessed for alarm features and shown markedly conflicting results. There is also no colonoscopy outcome data for other FBDs, such as functional constipation or functional diarrhea. Using the contemporaneous Rome IV criteria we determined the diagnostic yield of colonoscopy in patients with symptoms compatible with a FBD, stratified diligently according to the presence or absence of alarm features.

METHODS

Basic demographics, alarm features, and bowel symptoms using the Rome IV diagnostic questionnaire were collected prospectively from adults attending out-patient colonoscopy in 2019. Endoscopists were blinded to the questionnaire data. Organic disease was defined as the presence of inflammatory bowel disease, colorectal cancer, or microscopic colitis.

RESULTS

646 patients fulfilled symptom-based criteria for the following Rome IV FBDs: IBS (56%), functional diarrhea (27%) and functional constipation (17%). Almost all had alarm features (98%). The combined prevalence of organic disease was 12%, being lowest for functional constipation and IBS-constipation (∼6% each), followed by IBS-mixed (∼9%), and highest amongst functional diarrhea and IBS-diarrhea (∼17% each); p = .005. The increased prevalence of organic disease in diarrheal versus constipation disorders was accounted for by microscopic colitis (5.7% vs. 0%, p < .001) but not inflammatory bowel disease (7.2% vs. 4.0%, p = .2) or colorectal cancer (4.2% vs. 2.3%, p = .2). However, 1-in-4 chronic diarrhea patients - conceivably at risk for microscopic colitis - did not have colonic biopsies taken. Finally, only 11 of 646 (2%) patients were without alarm features, in whom colonoscopy was normal.

CONCLUSIONS

Most patients with symptoms of FBDs who are referred for colonoscopy have alarm features. The presence of organic disease is significantly higher in diarrheal versus constipation disorders, with microscopic colitis largely accounting for the difference whilst also being a missed diagnostic opportunity. In those patients without alarm features, the diagnostic yield of colonoscopy was nil.

Diagnosis and Treatment of Irritable Bowel Syndrome: Clinical Recommendations of the Russian Gastroenterological Association and Association of Coloproctologists of Russia

Aim. Current clinical recommendations accentuate current methods for the diagnosis and treatment of irritable bowel syndrome (IBS).

Key points.IBS is a functional bowel disorder manifested with recurrent, at least weekly, abdominal pain with the following attributes (any two leastwise): link to defecation, its frequency or stool shape. The symptoms are expected to persist for at minimum three months in a total six-month follow-up. Similar to other functional gastrointestinal (GI) disorders, IBS can be diagnosed basing on the patient symptoms compliance with Rome IV criteria, provided the absence of potentially symptom-causative organic GI diseases. Due to challenging differential diagnosis, IBS can be appropriately established per exclusionem, with pre-examination as follows: general and biochemical blood tests; tissue transglutaminase IgA/IgG antibody tests; thyroid hormones test; faecal occult blood test; hydrogen glucose/ lactulose breath test for bacterial overgrowth; stool test for enteric bacterial pathogens and Clostridium difficile A/B toxins; stool calprotectin test; abdominal ultrasound; OGDS, with biopsy as appropriate; colonoscopy with biopsy. The IBS sequence is typically wavelike, with alternating remissions and exacerbations often triggered by psychoemotional stress. Treatment of IBS patients includes dietary and lifestyle adjustments, various-class drug agents prescription and psychotherapeutic measures.

Conclusion. Adherence to clinical recommendations can facilitate timely diagnosis and improve medical aid quality in patients with different clinical IBS variants.

Functional Abdominal Pain Disorders and Constipation in Children on Gluten-Free Diet

BACKGROUND & AIMS

We studied the prevalence of functional abdominal pain disorders (FAPDs) and functional constipation (FC) in a large prospective cohort of children with celiac disease on a strict gluten-free diet (GFD).

METHODS

We performed a prospective cohort study, from 2016 through 2018, in a tertiary care center in Italy, of 417 patients (37% male; mean age, 13.7 y) with a diagnosis of celiac disease (European Society for Paediatric Gastroenterology Hepatology, and Nutrition criteria) who had been on a strict GFD for more than 1 year and had negative results from serologic tests after being on the GFD. Parents and children (>10 y) were asked to fill in a questionnaire on pediatric gastrointestinal symptoms, according to Rome IV criteria. Patients' closest siblings (or cousins) who had negative results from serologic test for celiac disease were used as controls (n = 373; 39% male; mean age, 13.5 y).

RESULTS

We found a higher prevalence of FAPDs among patients with celiac disease (11.5%) than controls (6.7%) (P < .05); the relative risk (RR) was 1.8 (95% CI, 1.1-3.0). Irritable bowel syndrome (IBS) and FC defined by the Rome IV criteria were more prevalent in patients with celiac disease (7.2% for IBS and 19.9% for FC) than controls (3.2% for IBS and 10.5% for FC) (P < .05 and P < .001, respectively); the RR for IBS was 2.3 (95% CI, 1.1-4.6) and the RR for functional constipation was 2.1 (95% CI, 1.4-3.2). We found no differences in the prevalence of other subtypes of FAPDs. A logistic regression showed that younger age (P < .05) and a higher level of anti-transglutaminase IgA at diagnosis (P < .04) were associated with FAPDs (in particular for IBS) irrespective of GFD duration.

CONCLUSIONS

Celiac disease is associated with an increased risk of IBS and FC. Strategies are needed to manage IBS and FC in patients with celiac disease.

Diagnostic yield of endoscopy in irritable bowel syndrome: A nationwide prevalence study 1987-2016

INTRODUCTION

Symptoms of irritable bowel syndrome (IBS) are common reasons for endoscopic procedures. We examined the yield of colonoscopy and upper endoscopy in IBS for several organic diseases.

METHODS

Matched population-based prevalence study in Sweden. We identified 21,944 participants diagnosed with IBS from 1987 to 2016 undergoing colonoscopy with a biopsy from all of Sweden's 28 pathology departments within 6 months of diagnosis. We compared prevalence of histopathology-proven diagnoses of inflammatory bowel disease (IBD), colorectal cancer, precancerous polyps, and microscopic colitis between patients recently diagnosed with IBS and matched controls without IBS (n = 81,101) undergoing colonoscopy. We also compared prevalence of celiac disease between patients diagnosed with IBS (n = 9,965) and matched controls (n = 45,584) undergoing upper endoscopy with biopsy. IBS patients were also compared to their siblings. Conditioned logistic regression estimated adjusted odds ratios (aORs).

RESULTS

Biopsy-proven IBD was seen in 1.6% of IBS and in 5.9% of controls (aOR=0.21; 95%CI=0.19-0.24). The prevalence of precancerous polyps was 4.1% vs. 13.0% (aOR=0.28; 95%CI=0.26-0.30), colorectal cancer 0.8% vs. 6.3% (aOR=0.17; 95%CI=0.14-0.20) and celiac disease 1.9% vs. 3.4% (aOR=0.54; 95%CI=0.47-0.63). Conversely, the prevalence of microscopic colitis was 2.9% vs. 1.7% (aOR=1.77; 95%CI=1.61-1.95), with higher prevalence in older patients and patients with IBS with diarrhea. Yield of colonoscopy for precancerous polyps, colorectal cancer, and microscopic colitis increased by age. Our findings were consistent using unaffected siblings as the comparator group.

DISCUSSION

The diagnostic yield of upper endoscopy and colonoscopy for organic disease is low in patients with a first-time diagnosis of IBS, though increases with age.

Review article: Diagnosis and investigation of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common disorder of gut-brain interaction. It is defined by the Rome criteria as the presence of abdominal pain, related to defaecation, associated with a change in stool form and/or frequency. The approach to diagnosis and investigation of suspected IBS varies between clinicians and, due in part to the uncertainty that can surround the diagnosis, many still consider it to be a diagnosis of exclusion. However, exhaustive investigation is both unnecessary and costly, and may also be counterproductive. Instead, physicians should aim to make a positive diagnosis, based on their clinical assessment of symptoms, and limit their use of investigations. The yield of routine blood tests in suspected IBS is low overall, but normal inflammatory markers may be reassuring. All patients should have serological testing for coeliac disease, irrespective of their predominant stool form. Routine testing of stool microbiology or faecal elastase is unnecessary; however, all patients with diarrhoea aged <45 should have a faecal calprotectin or a similar marker measured which, if positive, should lead to colonoscopy to exclude possible inflammatory bowel disease. Colonoscopy should also be undertaken in any patient reporting alarm symptoms suggestive of colorectal cancer, and in those whose presentation raises suspicion for microscopic colitis. Testing for bile acid diarrhoea should be considered for patients with IBS with diarrhoea where available. Hydrogen breath tests for lactose malabsorption or small intestinal bacterial overgrowth have no role in the routine assessment of suspected IBS. Adopting a standardised approach to the diagnosis and investigation of IBS will help to promote high-quality and high-value care for patients overall.

Frequency of Celiac Disease in Patients With Chronic Diarrhea

INTRODUCTION

Celiac disease (CD) is an immune-mediated disease caused by ingesting gluten-containing foods and is characterized mainly by malabsorptive diarrhea. Furthermore, distinguishing between mild disease and asymptomatic individuals is critical and necessitates a high level of clinical suspicion. Short stature, delayed puberty, bone abnormalities, neurological problems, and intestinal cancer can all be consequences of a delayed diagnosis. This study aimed to determine the prevalence of celiac disease among our community's recurrent diarrhea patients.

METHODS

This was a cross-sectional study aimed at determining the frequency of celiac disease in patients with chronic diarrhea. One hundred eighty-eight patients between the ages of 18 and 60 years who had chronic diarrhea lasting greater than three months were enrolled in this study. Stratification was utilized to control for modifiers. A p-value of ≤ 0.05 was considered significant.

RESULTS

A total of 74.5% of patients (n=140) were male, while 25.5% (n=48) were female with a mean age of 38.48±10.85 years. The average duration of celiac disease symptoms was 8.17± 3.75 months. Celiac disease was found in 12.2% (n=23) of the individuals. Also, 21% of individuals with a positive family history of CD devolved CD, compared to those without prior CD family history (p=0.01).

CONCLUSIONS

In individuals with chronic diarrhea for more than three months, the prevalence of celiac disease was determined to be 12.2% (n=23). There was a statistically significant difference between those with a positive family history of CD and those who did not have the condition.

Screening for Celiac Disease in Patients with Irritable Bowel Syndrome Fulfilling Rome III Criteria

Background Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. Celiac disease (CD), a treatable autoimmune enteropathy, with varied presentations, may simulate clinically symptoms of IBS. The aim of the present study is to screen for CD in patients with IBS diagnosed based on the Rome III criteria.

Patients and Methods A cross-sectional study was conducted at a secondary care gastrointestinal unit in Al-Salam General Hospital in Mosul city, Iraq, from November 2015 to October 2016. All patients fulfilling the Rome III criteria for IBS were screened for CD using antitissue transglutaminase IgA antibodies (anti-tTG). Patients who tested positive were subjected to endoscopic duodenal biopsy to confirm the diagnosis of CD.

Results A total of 100 patients were included in the present study (58 female and 42 male), the mean age of the participants was 40.8 years old (standard deviation [SD] ± 11.57). Ten patients (10/100, 10%) tested positive for anti-tTG antibodies. Five of the seropositive patients (5/10, 50%) showed positive biopsy results according to the Marsh classification, 3 of whom having diarrhea, and 2 with constipation.

Conclusion Positive serology and biopsy results suggestive of CD are common among patients with IBS. Screening patients with IBS for CD is justified.

Gluten-Free Diet Reduces Symptoms, Particularly Diarrhea, in Patients With Irritable Bowel Syndrome and Antigliadin IgG

BACKGROUND & AIMS

Many patients with irritable bowel syndrome (IBS) perceive that their symptoms are triggered by wheat-containing foods. We assessed symptoms and gastrointestinal transit before and after a gluten-free diet (GFD) in unselected patients with IBS and investigated biomarkers associated with symptoms.

METHODS

We performed a prospective study of 50 patients with IBS (ROME III, all subtypes), with and without serologic reactivity to gluten (antigliadin IgG and IgA), and 25 healthy subjects (controls) at a university hospital in Hamilton, Ontario, Canada, between 2012 and 2016. Gastrointestinal transit, gut symptoms, anxiety, depression, somatization, dietary habits, and microbiota composition were studied before and after 4 weeks of a GFD. HLA-DQ2/DQ8 status was determined. GFD compliance was assessed by a dietitian and by measuring gluten peptides in stool.

RESULTS

There was no difference in symptoms among patients at baseline, but after the GFD, patients with antigliadin IgG and IgA reported less diarrhea than patients without these antibodies (P = .03). Compared with baseline, IBS symptoms improved in 18 of 24 patients (75%) with antigliadin IgG and IgA and in 8 of 21 patients (38%) without the antibodies. Although constipation, diarrhea, and abdominal pain were reduced in patients with antigliadin IgG and IgA, only pain decreased in patients without these antibodies. Gastrointestinal transit normalized in a higher proportion of patients with antigliadin IgG and IgA. Anxiety, depression, somatization, and well-being increased in both groups. The presence of antigliadin IgG was associated with overall reductions in symptoms (adjusted odds ratio compared with patients without this antibody, 128.9; 95% CI, 1.16-1427.8; P = .04). Symptoms were reduced even in patients with antigliadin IgG and IgA who reduced gluten intake but were not strictly compliant with the GFD. In controls, a GFD had no effect on gastrointestinal symptoms or gut function.

CONCLUSIONS

Antigliadin IgG can be used as a biomarker to identify patients with IBS who might have reductions in symptoms, particularly diarrhea, on a GFD. Larger studies are needed to validate these findings. ClinicalTrials.gov: NCT03492333.