Association between Irritable Bowel Syndrome and Allergic Diseases: To Make a Case for Aeroallergen

Association between allergic diseases and mucosal healing in ulcerative colitis

Allergic diseases and ulcerative colitis (UC) share pathophysiological similarities. This study aimed to investigate the unclear association between allergic diseases and mucosal healing (MH), an important factor in the prognosis of UC. We studied 289 Japanese patients with UC. Information on allergic diseases (bronchial asthma, atopic dermatitis, pollen allergy, food allergy, and drug allergy), as diagnosed by physicians, was collected through self-reported questionnaires. The definition of MH was Mayo Endoscopic Score 0. The association between each allergic disease and its multimorbidity with MH was evaluated using multivariate logistic regression analyses. Pollen allergy was the most common allergic condition (36.3%). Pollen allergy and food allergy were independently associated with MH (pollen allergy adjusted OR: 1.82 [95% CI: 1.01-3.26]; food allergy adjusted OR: 3.47 [95% CI: 1.26-9.68]). The rates of MH for 0 and 3 or more allergic diseases were 24.6% and 4.2%, respectively. After adjustment for confounders, 3 or more allergic diseases were independently associated with MH (adjusted OR: 8.13 [95% CI: 2.17-34.04], p for trend = 0.020). This study demonstrates a significant positive association between specific allergic diseases (pollen and food allergies) and MH in UC patients, with a stronger association in cases of allergic multimorbidity.

The Effects of Environmental Factors on General Human Health: A Scoping Review

Background/Objectives: The external environment constantly influences human health through many factors, including air quality, access to green spaces, exposure to pollutants, and climate change. Contamination poses a substantial threat to human well-being; conversely, environmental factors also positively impact health. The purpose of this study is to provide a comprehensive review of the complex relationship between various environmental factors and human health. While individual studies have explored specific aspects, a broader integrative understanding is lacking. Methods: Through databases (PubMed, Cochrane, Copernicus), 4888 papers were identified, with 166 selected for detailed analysis. Results: We summarized recent research, identifying multiple associations between environmental factors such as air pollution, climate change, solar radiation, and meteorological conditions and their impact on various health outcomes, including respiratory, cardiovascular, metabolic and gastrointestinal, renal and urogenital, neurological and psychological health, infectious and skin diseases, and major cancers. We use chord diagrams to illustrate these links. We also show the interaction between different environmental factors. Findings begin with exploring the direct impact of environmental factors on human health; then, the interplay and combined effects of environmental factors, elucidating their (often indirect) interaction and collective contribution to human health; and finally, the implications of climate change on human health. Conclusions: Researchers and policymakers need to consider that individuals are exposed to multiple pollutants simultaneously, the "multipollutant exposure phenomenon". It is important to study and regulate environmental factors by considering the combined impact of various pollutants rather than looking at each pollutant separately. We emphasize actionable recommendations and solutions.

Irritable bowel syndrome: When food is a pain in the gut

Irritable bowel syndrome (IBS) is a chronic gastrointestinal condition associated with altered bowel habits and recurrent abdominal pain, often triggered by food intake. Current treatments focus on improving stool pattern, but effective treatments for pain in IBS are still lacking due to our limited understanding of pathophysiological mechanisms. Visceral hypersensitivity (VHS), or abnormal visceral pain perception, underlies abdominal pain development in IBS, and mast cell activation has been shown to play an important role in the development of VHS. Our work recently revealed that abdominal pain in response to food intake is induced by the sensitization of colonic pain-sensing neurons by histamine produced by activated mast cells following a local IgE response to food. In this review, we summarize the current knowledge on abdominal pain and VHS pathophysiology in IBS, we outline the work leading to the discovery of the role of histamine in abdominal pain, and we introduce antihistamines as a novel treatment option to manage chronic abdominal pain in patients with IBS.

Clinical and atopic features of patients with primary eosinophilic colitis: an Italian multicentre study

Eosinophilic colitis (EC) is the rarest among primary eosinophilic gastrointestinal disorders (EGID). EC is underdiagnosed due to its blurred and proteiform clinical manifestations. To explore the clinical and atopic characteristic of EC adult patients, the diagnostic delay, and relapse-associated factors, by comparison with patients with eosinophilic esophagitis (EoE) and irritable bowel syndrome (IBS). EC patients followed-up at four clinics were included, and clinical, histopathological, and laboratory data were retrieved. As control groups, age-matched patients with EoE and IBS were recruited. Allergy tests included skin prick test and serum specific IgE. Diagnostic delay was assessed. Overall, data from 73 patients were retrieved, including 40 with EC (median age 39 years IQR 22.5-59, F:M 2.1:1), 12 with EoE (F:M ratio: 1:5), and 21 with IBS (F:M ratio: 1:0.9). The most common features in EC patients were female sex (67.5%), atopy (77.5%), abdominal pain/distention (70%), diarrhoea (77.5%), and faecal calprotectin elevation (22.5%). Blood eosinophils were elevated in EoE, but not in EC (p < 0.001), while ECP did not differ across the three groups (p = 0.4). The frequency of allergen sensitization reached 25% of patients. Several frequent pan-allergens for this region were present. The overall diagnostic delay was 10 months (IQR 4-15). Factors contributing to a greater diagnostic delay were atopy, weight loss, and a previous misdiagnosis. EC is mostly a diagnosis of exclusion, burdened by a substantial diagnostic delay. In female patients the presence of allergen sensitization, abdominal symptoms and faecal calprotectin elevation should raise the suspicion of EC.

Uncovering a Severe Patient Group With Pollen-Related Extrarespiratory Allergic Symptoms: A Year-Long Diary Survey in Japan

BACKGROUND

The most common symptoms of pollen allergy are rhinitis and conjunctivitis. However, in real-world clinical practice, we sometimes encounter patients with pollen allergy suffering from severe extrarespiratory symptoms including skin, gastrointestinal, or flu-like symptoms in relation to exposure to sensitized pollen.

OBJECTIVE

To elucidate the extrarespiratory symptoms in patients with pollen allergy.

METHODS

We performed a non-drug-focused prospective study of patients with pollen allergy (n = 384). During the 1-year observational period, they were asked to complete a weekly electronic diary consisting of visual analog scale (VAS) scores to assess all symptoms experienced in various organs over the past week. An association between seasonal pollen levels and seasonal increase in VAS scores was evaluated using a mixed-effects model for repeated measures. A k-means cluster analysis was performed to identify a group of patients experiencing stronger extrarespiratory symptoms.

RESULTS

In patients sensitized to grass or birch pollen, higher seasonal levels of these pollen grains were associated with higher VAS scores for headache, gastrointestinal symptoms, skin symptoms, and fatigue. A cluster analysis identified a group of severe pollen-allergic patients with higher extrarespiratory symptoms (n = 42). This group was characterized by a higher frequency of comorbid food allergy/atopic dermatitis, higher rate of IgE sensitization to pollens, and higher impaired activity and work productivity.

CONCLUSIONS

This 1-year survey identified a small but nonnegligible group of patients with pollen-related extrarespiratory symptoms. More attention should be paid to this patient group considering their impaired activity and work productivity.

Multimorbidity of Allergic Diseases Is Associated With Functional Gastrointestinal Disorders in a Young Japanese Population

Background/Aims

Although certain allergic diseases have been reported to be associated with the prevalence of functional dyspepsia (FD) and irritable bowel syndrome (IBS), it is unclear whether the presence of multiple allergic diseases further increases the prevalence of FD and IBS. The aim of this study is to determine this issue in young people.

Methods

A cohort of 8923 Japanese university students was enrolled and diagnoses of FD and IBS were confirmed using Rome III criteria. Allergic disorders diagnosed at medical institutions were obtained by means of a self-administered questionnaire.

Results

The prevalence of FD, IBS, and their overlap was found to be 1.9%, 6.5%, and 1.1%, respectively. Pollen allergy was independently positively correlated with FD, IBS, and overlap of FD and IBS. Allergic rhinitis was positively linked to IBS. Drug allergy was positively associated with FD. The presence of multiple allergic diseases was positively correlated with FD and IBS (FD: adjusted OR for 2 allergic diseases: 1.95 [95% CI, 1.24-2.98], P for trend = 0.003; and IBS: adjusted OR for 1 allergic disease: 1.40 [95% CI, 1.15-1.69], 2 allergic diseases 1.47 [95% CI, 1.12-1.91], and 3 or more allergic diseases: 2.22 [95% CI, 1.45-3.28], P for trend = 0.001). Additionally, the concomitant existence of multiple allergic diseases was also demonstrated to have a trend that correlated with the overlap of FD and IBS (P for trend = 0.018).

Conclusion

Allergic disease multimorbidity is positively correlated with the prevalence of FD and IBS in a young population.

Italian guidelines for the management of irritable bowel syndrome in children and adolescents : Joint Consensus from the Italian Societies of: Gastroenterology, Hepatology and Pediatric Nutrition (SIGENP), Pediatrics (SIP), Gastroenterology and Endoscopy (SIGE) and Neurogastroenterology and Motility (SINGEM)

The irritable bowel syndrome (IBS) is a functional gastrointestinal disorder (FGID), whose prevalence has widely increased in pediatric population during the past two decades. The exact pathophysiological mechanism underlying IBS is still uncertain, thus resulting in challenging diagnosis and management. Experts from 4 Italian Societies participated in a Delphi consensus, searching medical literature and voting process on 22 statements on both diagnosis and management of IBS in children. Recommendations and levels of evidence were evaluated according to the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus was reached for all statements. These guidelines suggest a positive diagnostic strategy within a symptom-based approach, comprehensive of psychological comorbidities assessment, alarm signs and symptoms' exclusion, testing for celiac disease and, under specific circumstances, fecal calprotectin and C-reactive protein. Consensus also suggests to rule out constipation in case of therapeutic failure. Conversely, routine stool testing for enteric pathogens, testing for food allergy/intolerance or small intestinal bacterial overgrowth are not recommended. Colonoscopy is recommended only in patients with alarm features. Regarding treatment, the consensus strongly suggests a dietary approach, psychologically directed therapies and, in specific conditions, gut-brain neuromodulators, under specialist supervision. Conditional recommendation was provided for both probiotics and specific fibers supplementation. Polyethylene glycol achieved consensus recommendation for specific subtypes of IBS. Secretagogues and 5-HT4 agonists are not recommended in children with IBS-C. Certain complementary alternative therapies, antispasmodics and, in specific IBS subtypes, loperamide and rifaximin could be considered.

Dachengqi Decoction alleviates intestinal inflammation in ovalbumin-induced asthma by reducing group 2 innate lymphoid cells in a microbiota-dependent manner

Background and aim

Dachengqi Decoction (DCQD) as a classic traditional Chinese medicine has been reported to be effective in treating asthma, but its mechanism remains unknown. This study aimed to reveal the mechanisms of DCQD on the intestinal complications of asthma mediated by group 2 innate lymphoid cells (ILC2) and intestinal microbiota.

Experimental procedure

Ovalbumin (OVA) was used to construct asthmatic murine models. IgE, cytokines (e.g., IL-4, IL-5), fecal water content, colonic length, histopathologic appearance, and gut microbiota were evaluated in asthmatic mice treated with DCQD. Finally, we administered DCQD to antibiotic-treated asthmatic mice to measure the ILC2 in the small intestine and colon.

Results and conclusion

DCQD decreased pulmonary IgE, IL-4, and IL-5 levels in asthmatic mice. The fecal water content, the colonic length weight loss, and the epithelial damage of jejunum, ileum, and colon of asthmatic mice were ameliorated by DCQD. Meanwhile, DCQD greatly improved intestinal dysbiosis by enriching Allobaculum, Romboutsia and Turicibacter in the whole intestine, and Lactobacillus gasseri only in the colon. However, DCQD caused less abundant Faecalibaculum and Lactobacillus vaginalis in the small intestine of asthmatic mice. A higher ILC2 proportion in different gut segments of asthmatic mice was reversed by DCQD. Finally, significant correlations appeared between DCQD-mediated specific bacteria and cytokines (e.g., IL-4, IL-5) or ILC2. These findings indicate that DCQD alleviated the concurrent intestinal inflammation in OVA-induced asthma by decreasing the excessive accumulation of intestinal ILC2 in a microbiota-dependent manner across different gut locations.

Functional gastrointestinal disorders are associated with capsaicin cough sensitivity in severe asthma

BACKGROUND

Although sensory nerve dysfunction is related to the pathology of severe uncontrolled asthma and functional gastrointestinal disorders (FGIDs), the impact of comorbid FGIDs on the pathophysiology of severe uncontrolled asthma remains poorly understood. The aim was to clarify the physiological relationships between severe uncontrolled asthma and FGIDs.

METHODS

Fifty-two patients with severe uncontrolled asthma who visited our hospital between September 2016 and August 2019 were retrospectively analyzed. Clinical characteristics, other comorbidities including gastroesophageal reflux disease (GERD), and biomarkers such as fractional nitric oxide (FeNO) and capsaicin cough sensitivity (C-CS) before the beginning of biologics or bronchial thermoplasty, were compared between patients with and without comorbid FGIDs. C-CS was evaluated by C5 (concentration of inhaled capsaicin that induced five or more coughs), and C5 ≤2.44 μM was defined as heightened C-CS.

RESULTS

Seventeen patients had comorbid FGIDs. These patients had a lower FeNO level (21.9 ± 1.7 ppb vs. 33.9 ± 2.8 ppb, P = 0.04), a lower C5 threshold (2.24 ± 2.88 μM vs. 8.91 ± 5.5 μM, P < 0.001), a higher prevalence of comorbid GERD (64.7% vs. 31.7%, P = 0.03), and a higher prevalence of heightened C-CS (70.6% vs. 28.6%, P = 0.007) than those without FGIDs. Analysis of covariance showed a significant effect of FGIDs on C-CS in severe uncontrolled asthma without being affected by GERD.

CONCLUSIONS

Comorbid FGIDs are associated with heightened C-CS in patients with severe uncontrolled asthma, and they may be an important extra-respiratory manifestation of the airway neuronal dysfunction phenotype of severe uncontrolled asthma.

Irritable bowel syndrome is strongly associated with the primary and idiopathic mast cell disorders

BACKGROUND

Mounting evidence supports a mechanistic association between irritable bowel syndrome (IBS) symptoms and mast cell hyperactivity. Yet, association between IBS and mast cell disorders (MCDs) has not been studied. We examined this association using two large databases and verified with manual chart review.

METHODS

The IBM Watson Health Explorys database (Somers, NY), an aggregate of electronic health record (EHR) data from over two dozen US healthcare systems, and Epic's SlicerDicer tool, a self-service tool containing de-identified data from the Epic EHR, were used to identify patients with IBS and MCDs. Patients with organic gastrointestinal disease or diseases associated with secondary mast cell hyperproliferation were excluded. Results were verified with manual chart review from two academic centers.

KEY RESULTS

Up to 4% of IBS patients had a comorbid MCD. IBS was strongly associated with all MCDs. The strongest association was between IBS and mast cell activation syndrome (OR 16.3; 95% CI 13.1-20.3). Odds ratios for IBS+urticaria, IBS+idiopathic urticaria, IBS+non-malignant mastocytosis, and IBS+mast cell malignancy ranged from 4.5 to 9.9. Patients from each of these overlap cohorts were predominantly female, and the overlap occurred with all IBS subtypes. Thorough endoscopic evaluation and comorbid mood disorders and migraines are more common in the overlap cohorts than in IBS alone.

CONCLUSIONS/INFERENCES

In a large US database encompassing >53 million patients over >20 years, patients with IBS are at least 4 times more likely to have a MCD than the general population. Further study of mast cell involvement in the pathogenesis of IBS is warranted.

The clinical burden of cow's milk allergy in early childhood: A retrospective cohort study

Introduction

Cow's milk allergy (CMA) is common in infants and children. Clinical presentations may vary, with a range of symptoms affecting the gastrointestinal (GI), skin and respiratory systems. Whilst the primary focus of research to date has been on the management of these symptoms, studies investigating the broader clinical burden of CMA are limited.

Methods

We performed a retrospective matched cohort study examining clinical data, including allergic symptoms and infections, extracted from case records within The Health Improvement Network database. A total of 6998 children (54% male) were included in the study, including 3499 with CMA (mean age at diagnosis 4.04 months) and 3499 matched controls without CMA, observed for a mean period of 4.2 years.

Results

GI, skin and respiratory symptoms affected significantly more children with CMA (p < .001), which recurred more often (p < .001), compared with children without CMA. More children with CMA had symptoms affecting multiple systems (p < .001). CMA was associated with a greater probability of these symptoms requiring hypoallergenic formula (HAF) prescription persisting over time (log‐rank test p < .0001, unadjusted hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.76–0.85, p < .001), with a longer median duration of symptoms and HAF prescription compared with the duration of symptoms in those without CMA (3.48 vs. 2.96 years). GI, skin, respiratory and ear infections affected significantly more children with CMA than those without, increasing by 74% (p < .001), 20% (p < .001), 9% (p < .001), and 30% (p < .001) respectively. These infections also recurred more often among children with CMA, increasing by 62% for GI infections, 37% for skin and respiratory infections, and 44% for ear infections (p < .001).

Conclusions

This real‐world study provides evidence to suggest that CMA presents a significant clinical burden to children, which has implications for the healthcare system. Further research is warranted to understand the health economic impact of this, and the phenotypes, factors and management approaches which may affect clinical outcomes.

How to manage irritable bowel syndrome in children

AIM

This paper discusses the risk factors and management of paediatric irritable bowel syndrome (IBS), with a focus on the role of the gastrointestinal microbiome.

METHODS

English articles of interest published in PubMed and Google Scholar were searched using subject heading and keywords of interest.

RESULTS

Only few randomised controlled trials on the management of IBS in children have been published. The vast majority of these intervention trials target to change the composition of the gastrointestinal microbiome. Most studies are underpowered. Major heterogeneities in study designs such as differences in inclusion criteria, including patients with different pain-related functional gastrointestinal disorders and differences in primary outcomes, make it impossible to formulate recommendations. Overall, few adverse events are reported what could indicate safety or point to suboptimal conduction of clinical trials and safety reporting. However, it can also not be excluded that some interventions such as the administration of selected probiotic products may result in benefit.

CONCLUSION

There is insufficient evidence to recommend any therapeutic intervention in paediatric IBS, including manipulation of the gastrointestinal tract microbiome, despite the evidence that dysbiosis seems an associated pathophysiologic factor. More designed prospective trials are needed since IBS is not a rare condition during childhood.

Colonic Mucosal Immune Activation in Mice with Ovalbumin-Induced Allergic Airway Disease: Association between Allergic Airway Disease and Irritable Bowel Syndrome

Recent studies on the pathophysiology of irritable bowel syndrome (IBS) have focused on the role of mast cells (MCs) in intestinal mucosal immunity. A link between allergic airway diseases (AADs) and IBS has been suggested because both diseases have similar pathophysiology. We aimed to investigate whether the induction of AAD in mice could lead to inflammation of the colonic mucosa, similar to IBS. We also evaluated whether this inflammatory response could be suppressed by administering a therapeutic agent. Mice were divided into three groups: control, AAD-induced, and salbutamol-treated. An AAD mouse model was established by intraperitoneal injection and nasal challenge with ovalbumin. Mice with AAD were intranasally administered salbutamol. Analyses of cytokine levels, MC count, and tryptase levels in the intestinal mucosa were performed to compare the changes in inflammatory responses among the three groups. Inflammation was observed in the intestinal mucosa of mice in the AAD group. This inflammation in AAD mice was suppressed after salbutamol treatment. Our study demonstrates that AAD induces an inflammatory response similar to that in IBS, suggesting a possible association between IBS and AADs. In patients with IBS with such allergic components, salbutamol may have the potential to alleviate the inflammatory response.

Brain to Belly: Abdominal Variants of Migraine and Functional Abdominal Pain Disorders Associated With Migraine

Migraine is one of the most frequent causes of primary headache and 9% of children suffer from migraines. Most children will continue to experience migraine attacks as adults, therefore it is imperative that we have a thorough understanding of this major health issue. This article considers the so-called abdominal variants of migraine, which are more commonly seen in children rather than adults: abdominal migraine, cyclic vomiting syndrome, and infantile colic. Other functional abdominal pain disorders such as irritable bowel syndrome and functional dyspepsia have also been linked to migraine in clinical studies. The common pathophysiological root of these diseases seems to be the gut-brain axis mechanism. Abdominal variants of migraine are considered pediatric precursors of migraine whereas the functional abdominal pain disorders related to migraine seem to share a pathophysiological root with no temporarily link as for today. In this review we aim to describe the epidemiological background, the current pathophysiological theories and the relationship of each disease to migraine. This review is the first to compile abdominal variants of migraine and functional abdominal pain disorders associated with migraine and we endeavor to elucidate the broad spectrum of migraine-related episodes in children.

Update on the Role of Allergy in Pediatric Functional Abdominal Pain Disorders: A Clinical Perspective

Both functional abdominal pain disorders (FAPDs) and food allergies are relatively common in children and adolescents, and most studies report an association between FAPDs and allergic conditions. FAPDs share pathophysiologic processes with allergies, including both immune and psychological processes interacting with the microbiome. No conclusive data are implicating IgE-mediated reactions to foods in FAPDs; however, there may be patients who have IgE reactions localized to the gastrointestinal mucosa without systemic symptoms that are not identified by common tests. In FAPDs, the data appears stronger for aeroallergens than for foods. It also remains possible that food antigens initiate an IgG reaction that promotes mast cell activation. If a food allergen is identified, the management involves eliminating the specific food from the diet. In the absence of systemic allergic symptoms or oral allergy syndrome, it appears unlikely that allergic triggers for FAPDs can be reliably identified by standard testing. Medications used to blunt allergic reactions or symptomatically treat allergic reactions may be useful in FAPDs. The purpose of the current manuscript is to review the current literature regarding the role of allergy in FAPDs from a clinical perspective, including how allergy may fit in the current model of FAPDs.

Non-IgE-Mediated Gastrointestinal Food Allergies in Children: An Update

Non-immunoglobulin E-mediated gastrointestinal food allergic disorders (non-IgE-GI-FA) include food protein-induced enterocolitis syndrome (FPIES), food protein-induced enteropathy (FPE) and food protein-induced allergic proctocolitis (FPIAP), which present with symptoms of variable severity, affecting the gastrointestinal tract in response to specific dietary antigens. The diagnosis of non-IgE-GI-FA is made clinically, and relies on a constellation of typical symptoms that improve upon removal of the culprit food. When possible, food reintroduction should be attempted, with the documentation of symptoms relapse to establish a conclusive diagnosis. Management includes dietary avoidance, nutritional counselling, and supportive measures in the case of accidental exposure. The prognosis is generally favorable, with the majority of cases resolved before school age. Serial follow-up to establish whether the acquisition of tolerance has occurred is therefore essential in order to avoid unnecessary food restriction and potential consequent nutritional deficiencies. The purpose of this review is to delineate the distinctive clinical features of non-IgE-mediated food allergies presenting with gastrointestinal symptomatology, to summarize our current understanding of the pathogenesis driving these diseases, to discuss recent findings, and to address currents gaps in the knowledge, to guide future management opportunities.