A 8-year population-based cohort study of irritable bowel syndrome in childhood with history of atopic dermatitis

Role of gut-derived bacterial lipopolysaccharide and peripheral TLR4 in immobilization stress-induced itch aggravation in a mouse model of atopic dermatitis

Psychological stress and intestinal leakage are key factors in atopic dermatitis (AD) recurrence and exacerbation. Here, we demonstrate the mechanism underlying bacterial translocation across intestinal epithelial barrier damaged due to stress and further aggravation of trimellitic anhydride (TMA)-induced itch, which remain unclear, in AD mice. Immobilization (IMO) stress exacerbated scratching bouts and colon histological damage, and increased serum corticosterone and lipopolysaccharide (LPS). Orally administered fluorescein isothiocyanate (FITC)-dextran and surgically injected (into the colon) Cy5.5-conjugated LPS were detected in the serum and skin after IMO stress, respectively. The relative abundance of aerobic or facultative anaerobic bacteria was increased in the colon mucus layer, and Lactobacillus murinus, E. coli, Staphylococcus nepalensis, and several strains of Bacillus sp. were isolated from the spleens and mesenteric lymph nodes. Oral antibiotics or intestinal permeability blockers, such as lubiprostone (Lu), 2,4,6-triaminopyrimidine (TAP) and ML-7, inhibited IMO stress-associated itch; however, it was reinduced through intradermal or i.p. injection of LPS without IMO stress. I.p. injection of TAK-242 (resatorvid), a TLR4 inhibitor, abrogated IMO stress-associated itch, which was also confirmed in TLR4-KO mice. IMO stress alone did not cause itch in naïve mice. IMO stress-induced itch aggravation in TMA-treated AD mice might be attributed to the translocation of gut-derived bacterial cells and LPS, which activates peripheral TLR4 signaling.

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.

Evolutionary medicine approaches to chronic disease: The case of irritable bowel syndrome

Irritable bowel syndrome (IBS), a gastrointestinal disease, is a global phenomenon correlated with industrialization. We propose that an evolutionary medicine approach is useful to understand this disease from an ultimate perspective and conducted a scoping literature review to synthesize the IBS literature within this framework. Our review suggests five potential evolutionary hypotheses for the cause of IBS, including (a) a dietary mismatch accompanying a nutritional transition, (b) an early hygienic life environment leading to the immune system and microbiotic changes, (c) an outcome of decreased physical activity, (d) a response to changes in environmental light-dark cycles, and (e) an artifact of an evolved fight or flight response. We find key limitations in the available data needed to understand early life, nutritional, and socioeconomic experiences that would allow us to understand evolutionarily relevant risk factors and identify a need for further empirical research to distinguish potential causes and test evolutionary hypotheses.

Gastrointestinal Comorbidities Associated with Atopic Dermatitis-A Narrative Review

The current understanding of atopic dermatitis (AD) seems to be extending beyond a skin-confined condition frequently associated with allergic comorbidities, as in a number of epidemiological studies, the prevalence rate of a range of illnesses has been determined to be greater in patients with AD, or inversely. In most cases, the reasons for this are vague. A subset of these conditions are gastrointestinal disorders, including food sensitization (FS) and food allergy (FA), eosinophilic esophagitis (EoE) (it is of mixed background, both IgE-dependent and independent), food protein-induced enterocolitis syndrome (FPIES) (it exemplifies an IgE-independent food allergy), Crohn's disease (CD), colitis ulcerosa (CU), celiac disease, irritable bowel syndrome (IBS), and gastroesophageal reflux disease (GERD). In this review, we performed a comprehensive search of the literature using the PubMed database. We addressed the epidemiology of the increased co-occurrence of these diseases with AD and discussed potential causes for this subject. Multiple gastroenterological comorbidities appear to be more common in patients with AD, according to our review. The mechanisms that underlie this phenomenon are largely unknown, highlighting the need for further study in this field.

Early life adverse exposures in irritable bowel syndrome: new insights and opportunities

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder worldwide. Extensive research has identified multiple factors contributing to its development, including genetic predisposition, chronic infection, gut dysbiosis, aberrant serotonin metabolism, and brain dysfunction. Recent studies have emphasized the critical role of the early life stage as a susceptibility window for IBS. Current evidence suggests that diet can heighten the risk of IBS in offspring by influencing the microbiota composition, intestinal epithelium structure, gene expression, and brain-gut axis. The use of antibiotics during pregnancy and the neonatal period disrupts the normal gut microbiota structure, aligning it with the characteristics observed in IBS patients. Additionally, early life stress impacts susceptibility to IBS by modulating TLR4, NK1, and the hypothalamic-pituitary-adrenal (HPA) axis while compromising the offspring's immune system. Formula feeding facilitates the colonization of pathogenic bacteria in the intestines, concurrently reducing the presence of probiotics. This disruption of the Th1 and Th2 cell balance in the immune system weakens the intestinal epithelial barrier. Furthermore, studies suggest that delivery mode influences the occurrence of IBS by altering the composition of gut microbes. This review aims to provide a comprehensive summary of the existing evidence regarding the impact of adverse early life exposures on IBS during pregnancy, intrapartum, and neonatal period. By consolidating this knowledge, the review enhances our understanding of the direct and indirect mechanisms underlying early life-related IBS and offers new insights and research directions from childhood to adulthood.

Atopic dermatitis is associated with abnormal stool form: a population-based cross-sectional study in college students

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disorder. Bristol Stool Form Scale (BSFS) is a widely used stool scoring method that could indirectly reflect intestinal function.

OBJECTIVES

To evaluate the associations of AD with BSFS.

METHODS

This was a population-based cross-sectional study of freshmen in five universities of China. AD diagnosis was performed by dermatologists according to the guideline from the American Academy of Dermatology. BSFS and covariates were collected through an online questionnaire survey. Chronic itch scores were assessed by the numeric rating scales and grouped into quartiles (Q). Mixed logistic regression models were used. Subgroup analysis was conducted by covariates. P value < 0.05 was considered statistically significant.

RESULTS

The prevalence of hard stools and loose stools were 8.9% and 7.6%, respectively (20,049 participants). After adjusting covariates, AD was significantly associated with hard stools (OR = 1.38, P < 0.001) and loose stools (OR = 1.24, P = 0.037). In subgroup analysis of hard stool, a stronger effect was observed in intake of milk (> 3 days/week), yogurt (> 3 days/week), pork (< 1 day/week), and higher itch scores (Q4).

CONCLUSION

This study found the relationship between AD and abnormal stool forms, and the association with hard stools might be modified by dietary factor.

The Multiomics Analyses of Gut Microbiota, Urine Metabolome and Plasma Proteome Revealed Significant Changes in Allergy Featured with Indole Derivatives of Tryptophan

Objective

To explore changes in the gut microbiota (GM), urine metabolome and plasma proteome in individuals with allergies using multiomics analyses, and identify the key components and mechanism.

Methods

This was a cross-sectional study. All subjects were recruited to collect fecal, urine and blood samples. 16S rDNA sequencing was used to analyze the structure and function of the GM, liquid chromatography mass spectrometry was used to quantify metabolites in the urine, and data-independent acquisition quantitative proteome analysis was used to detect proteins in the plasma. Differences in GM, urine metabolites and plasma proteins between allergic and healthy individuals were displayed using principal component analysis (PCoA) and heatmap, and the co-occurrence network was visualized in Cytoscape using Spearman correlation among differential predominant genera, metabolites and proteins. The functional analysis was performed according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) dataset. The allergy-related cytokines, IL-4, IL-6 and IL-13, were measured to evaluate the effect of indole derivatives on LPS-induced macrophage activation.

Results

GM α indexes, β distances and the relative abundance of the core differential genera in the allergic group were different from those of healthy individuals, which resulted in a separate distribution in the PCoA and enterotypes. Similarly, the concentrations of 393 metabolites and 144 proteins were different between allergic and healthy individuals. Then, 634 significant correlations were identified among 6 predominant differential genera, 24 differential metabolites and 104 differential proteins, 301 of which were negative and 333 of which were positive. Notably, a core network centered on tryptophan metabolites, indole-3-butyric acid (IBA) and indole-3-lactic acid (ILA), displayed high consistency with the results of KEGG pathway analysis. In the LPS-stimulated macrophages, IBA reduced the expression of IL-4 and IL-6, and ILA inhibited the upregulation of IL-6.

Conclusion

The GM, urine metabolome and plasma proteome underwent systematic change in allergic individuals compared to healthy individuals, among which indole derivatives from tryptophan metabolism might play key roles in the progression of allergies and could serve as therapeutic targets of allergy.

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

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.

Prevalence and Comorbidity of Atopic Dermatitis in Children: A Large-Scale Population Study Based on Real-World Data

This study aimed at exploring atopic dermatitis (AD) prevalence in children and exhaustively analyzing their comorbidity. We conducted a descriptive analysis of their socio-demographic and comorbidity characteristics in the EpiChron Cohort (Aragón, Spain). Adjusted odds ratios (OR) were calculated for each comorbidity using logistic regression models. In total, 33,591 children had a diagnosis of AD, resulting in an overall prevalence of 15.5%. AD prevalence was higher in girls compared to boys, in 3–9-year-olds compared to children of other ages, and in Spanish children compared to those of other nationalities. Multimorbidity was present in 43% of children, with the most frequent chronic comorbidities being asthma (13.1%), psychosocial disorders (7.9%), and visual impairment (7.8%). Many diseases were, regardless of their prevalence, statistically associated with AD. The strongest associations (odds ratio (OR) (95% confidence interval (CI))) were found in asthma (2.10 (2.02–2.17)), allergic rhinitis (2.00 (1.91–2.10)), and irritable bowel syndrome (1.90 (1.56–2.31)). A better understanding of the array of comorbidities associated with AD in children might help improve their clinical management. Future longitudinal studies are encouraged to shed light on the potential underlying pathophysiological mechanisms involved in the identified associations.

Approach to the Assessment and Management of Pediatric Patients with Atopic Dermatitis: A Consensus Document. Section II: Comorbid Disease in Pediatric Atopic Dermatitis

Pediatric atopic dermatitis (AD) is one of the most common skin conditions encountered by health-care providers caring for infants, children, and adolescents. Pediatric patients with AD may present with other allergic and nonallergic comorbidities that require appropriate treatment and referral. They may also experience a trajectory of allergic diseases known as the atopic march, which depends on a complex interaction between genetic and environmental factors and likely involves early epidermal barrier dysfunction. Here we provide a review and clinical recommendations on the assessment and referral of comorbidities in pediatric AD.

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

Irritable bowel syndrome (IBS) is a functional gastrointestinal disease and the most common cause of prolonged abdominal pain and bowel disturbances in the developed world. While initially thought to be functional or psychosomatic in nature, IBS is now recognized as a heterogeneous group of conditions. A subset of IBS patients and patients with allergic diseases share some characteristic inflammatory features. In fact, atopic children show an increased likelihood of developing IBS as adults. Given these findings, a subset of IBS may be suffering from allergy-related gut diseases. In this review, we present the allergy-related comorbidities of IBS, including genetic, environmental, and immunologic factors. We discuss studies demonstrating an increased sensitization of IBS patients to aeroallergens compared to food allergens. We then postulate potential pathophysiological mechanisms underlying both IBS and aeroallergens in the gut, followed by potential implications in the screening and treatment of allergies in IBS patients.

Atopic Dermatitis in Adults and Irritable Bowel Syndrome: A Cross-sectional Study

BACKGROUND

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder affecting a large number of people in the world. Atopic dermatitis (AD) is a common inflammatory skin condition characterized by relapsing eczematous lesions in a typical distribution. It was first described in 1933 but exists since antiquity.

AIM AND OBJECTIVES

To determine the relationship between AD and IBS.

MATERIALS AND METHODS

A total of 109 patients with AD and 100 healthy controls were included in the study. They were defined for diagnosis of IBS according to ROME-III diagnostic criteria. Supporting findings, Bristol stool scale, frequency of defecation and history of AD and IBS were also evaluated. AD severity was assessed using Severity Scoring of Atopic Dermatitis index.

RESULTS

A total of 62 patients (56.9%) in the AD group and 28 patients (28%) in the control group were diagnosed with IBS (P<0.001). Supportive findings excluding abnormal stool frequency and passage of mucus were more frequent in AD patients. There was no significant relationship between disease severity according to SCORAD index and variables in AD patients.

CONCLUSIONS

This is a rather uncultivated area in the field of AD. We observed that IBS was more common in AD group. Also, supporting findings like abnormal stool form, abdominal distension, feeling of incomplete evacuation, and straining were found more frequently in AD patients. These results may indicate the association between AD and IBS. In our opinion, patients with atopic dermatitis should be questioned in terms of IBS.

Allergic rhinitis and the associated risk of nocturnal enuresis in children: a population-based cohort study

BACKGROUND

Despite controversy, an association between allergy and nocturnal enuresis (NE) has been reported for almost a century. Allergic rhinitis (AR)-associated sleep-disordered breathing frequently results in microarousals during sleep, decreased sleep efficiency, and change in sleep pattern and behavior. NE is a common sleep disorder in children. Hence, this study aimed to investigate the incidence and risk of NE in children with AR.

METHODS

A population-based cohort study was conducted among 327,928 children with AR and 327,601 non-AR controls between 2000 and 2012 in Taiwan. By the end of 2012, the incidence of NE in both cohorts, and the AR-to-non-AR cohort hazard ratios (HRs) were measured.

RESULTS

The adjusted HR of NE during the study period was 1.7-fold higher in the AR cohort compared to the non-AR cohort. The risk was greater for boys, children younger than 6 years old, those with comorbidities of asthma, atopic dermatitis, and attention deficit/hyperactivity disorder (ADHD), and those who had more than 5 AR-related medical visits per year. The risk of NE in the AR cohort decreased with follow-up time and was the highest within the first year after AR diagnosis.

CONCLUSION

Children with AR had a higher incidence and subsequent risk of NE. The risk of NE was greater for boys, younger children, and those with more frequent health utilization for AR symptoms.

Children with allergic diseases have an increased subsequent risk of migraine upon reaching school age

The association between migraine and allergy has remained a subject of debate for more than a century. To systemically investigate the interaction between children with antecedent allergic diseases and their future risks of migraine on reaching school age, we recruited 16,130 children aged 7-18 with migraine diagnosed between 2000 and 2008, and 64,520 matched controls without a history of migraine. The ORs of migraine were calculated for the association with allergic diseases diagnosed before migraine diagnosis. The allergic diseases included atopic dermatitis, allergic conjunctivitis, allergic rhinitis (AR), and asthma. Children with preceding allergic diseases had a greater subsequent risk of migraine than the controls. Among the four evaluated diseases, AR had the highest adjusted OR (aOR) of 2.17 (95% CI 2.09 to 2.26). Children with all four allergic diseases had the highest aOR of 3.59 (95% CI 2.91 to 4.44). Further, an increasing trend of aORs was observed with more allergic disease-associated medical consulting. Our study indicates that children with allergic diseases are at increased subsequent risk of migraine when they reach school age, and the risk shows a cumulative effect of more allergic diseases and more allergy-related healthcare.