Atopic Dermatitis: Disease Background and Risk Factors

Mendelian Randomization Studies in Atopic Dermatitis: A Systematic Review

Prior studies have found associations between atopic dermatitis (AD) and comorbidities, including depression, obesity, asthma, and allergic rhinitis. Although observational studies often cannot establish robust causality between potential risk factors and AD, Mendelian randomization minimizes confounding when exploring causality by relying on random allelic assortment at birth. In this study, we systematically reviewed 30 Mendelian randomization studies in AD. Body mass index, gut microbial flora, the IL-18 signaling pathway, and gastroesophageal reflux disease were among the causal factors for AD, whereas AD was causal for several medical conditions, including heart failure, rheumatoid arthritis, and conjunctivitis. These insights may improve preventive counseling in AD.

Advancements in Allergen Immunotherapy for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin condition that affects individuals of all age groups, manifesting as a spectrum of symptoms varying from mild to severe. Allergen immunotherapy (AIT) involves the administration of allergen extracts and has emerged as a potential treatment strategy for modifying immune responses. Its pathogenesis involves epidermal barrier dysfunction, microbiome imbalance, immune dysregulation, and environmental factors. Existing treatment strategies encompass topical steroids to systemic agents, while AIT is under investigation as a potential immune-modifying alternative. Several studies have shown reductions in the severity scoring of atopic dermatitis (SCORAD) scores, daily rescue medication use, and visual analog scale (VAS) scores following AIT. Biomarker changes include increased IgG4 levels and decreased eosinophil counts. This review provides valuable insights for future research and clinical practice, exploring AIT as a viable option for the management of AD.

Systemic Type 2 Inflammation-Associated Atopic Dermatitis Exacerbates Periodontitis

INTRODUCTION

Atopic dermatitis (AD) is a prevalent and chronic inflammatory skin disease characterized by Th2 cell-mediated type 2 inflammation. Emerging evidence indicated that AD patients exhibit an increased incidence of oral disorders. In the present study, we sought mechanistic insights into how AD affects periodontitis.

METHODS

Onset of AD was induced by 2,4-dinitrochlorobenzene (DNCB). Furthermore, we induced periodontitis (P) in AD mice. The effect of AD in promoting inflammation and bone resorption in gingiva was evaluated. Hematoxylin and eosin staining, tartrate-resistant acid phosphatase staining, immunofluorescence assay, and flow cytometry were used to investigate histomorphology and cytology analysis, respectively. RNA sequencing of oral mucosa is used tissues to further understand the dynamic transcriptome changes. 16S rRNA microbial analysis is used to profile oral microbial composition.

RESULTS

Compared to control group, mice in AD group showed inflammatory signatures and infiltration of a proallergic Th2 (Th2A)-like subset in oral mucosa but not periodontitis, as identified by not substantial changes in mucosa swelling, alveolar bone loss, and TRAP+ osteoclasts infiltration. Similarly, more Th2A-like cell infiltration and interleukin-4 levels were significantly elevated in the oral mucosa of DNCB-P mice compared to P mice. More importantly, AD exacerbates periodontitis when periodontitis has occurred and the severity of periodontitis increased with aggravation of dermatitis. Transcriptional analysis revealed that aggravated periodontitis was positively correlated with more macrophage infiltration and abundant CCL3 secreted. AD also altered oral microbiota, indicating the re-organization of extracellular matrix.

CONCLUSIONS

These data provide solid evidence about exacerbation of periodontitis caused by type 2 dermatitis, advancing our understanding in cellular and microbial changes during AD-periodontitis progression.

Defining the temporal relationship between the skin microbiome, immune response and skin barrier function during flare and resolution of atopic dermatitis: protocol of a Danish intervention study

INTRODUCTION

Lesional skin of atopic dermatitis (AD) is often colonised by Staphylococcus aureus and the bacterial abundance increases during a flare. However, the role of S. aureus and the skin microbiome in the pathogenesis of AD, including its influence on the dysfunctional skin barrier and immune response, remains to be elucidated. In this study, the temporal relationship between alterations in the skin barrier function, inflammation and microbiome is examined in adults with AD.

METHODS AND ANALYSIS

This clinical study consists of 81 adult patients with AD, as defined by the Hanifin and Rajka criteria, and 41 age and sex-matched controls. The objectives are to examine alterations in the skin microbiome, skin barrier and immune response during (1) an untreated AD flare, (2) an AD flare treated with topical corticosteroids (TCS), (3) an AD flare treated with systemic dicloxacillin/placebo and TCS or (4) cutaneous exposure to either autologous S. aureus, staphylococcal enterotoxin B or a vehicle. Skin biopsies, tape strips, skin and nasal swabs are collected and analysed using RNA sequencing, multiplex immunoassays, liquid chromatography-mass spectrometry and 16S rDNA. Blood samples are analysed for filaggrin gene mutations and leucocyte gene expression.

ETHICS AND DISSEMINATION

The scientific Ethical Committee of the Capital Region in Denmark (phases I and II: H-20011047, phases III and IV: H-21079287), the local data protection agency (phases I and II: P-2020-165, phases III and IV: P-2022-250) and the Danish Medicines Agency (phases III and IV: EudraCT 2021-006883-25, ClinicalTrials.gov: NCT05578482) have approved the studies. Participants will give written informed consent prior to study initiation. The study is conducted in accordance with the Helsinki Declaration. Outcomes will be presented at national and international conferences and in international peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT05578482, EudraCT 2021-006883-2.

Allergic March in Children: The Significance of Precision Allergy Molecular Diagnosis (PAMD@) in Predicting Atopy Development and Planning Allergen-Specific Immunotherapy

The allergic march is a progression of naturally occurring symptoms whose nature changes with age. The classic allergic march typically begins in infancy and manifests in the form of atopic dermatitis and food allergy. As immune tolerance develops over time, these conditions may resolve by the age of 3-5 years; however, they may evolve into allergic rhinitis and bronchial asthma. Traditional diagnostic assessments, such as skin prick testing or serum allergen-specific immunoglobulin E (sIgE) level testing, are conducted to introduce effective treatment. Recent years saw the emergence of precision allergy molecular diagnosis (PAMD@), which assesses sIgE against allergenic molecules. This new technology helps more accurately evaluate the patient's allergy profile, which helps create more precise dietary specifications and personalize allergen-specific immunotherapy. This review presents possible predictions regarding the allergic march and the means of controlling it based on PAMD@ results.

Detection and assessment of dust mite allergens in an indoor environment in Anhui, China

Dust in the home environment is thought to be a potential trigger for increasing allergic diseases, such as allergic rash, rhinitis, asthma, and other conditions, associated with dust mites. To verify the status of dust mite prevalence in indoor surroundings, we collected 189 dust samples from the air conditioner filters (n = 75) and floors (n = 114) of households, schools, and hotels in the Anhui area, China. All samples were measured for dust mite breeding rate and breeding density under light microscopy and analyzed for dust mite species Dermatophagoides farinae 1 (Der f 1) and Dermatophagoides pteronyssinus 1 (Der p 1) allergen using enzyme-linked immunosorbent assay (ELISA). The dust mite breeding rates were 34.67% (26/75) and 20.18% (23/114), respectively, in the dust samples from the floor and air conditioning filters. The breeding density was the highest in households (10/g), followed by schools (9/g) and hotels (4/g). ELISA indicated that the allergen threshold (2.0 µg/g dust) of Der f 1 was exceeded in only two samples and Der p 1 in one sample. Additionally, a questionnaire was used to investigate the health knowledge on allergic diseases involved in indoor facilities, finding that most allergy sufferers were aware that indoor dust might be responsible for their conditions. The findings suggest that regular maintenance of indoor hygiene and cleaning of air-conditioning filters should reduce the risks of exposure to indoor allergens.

Asthma, allergic rhinitis and atopic dermatitis in association with home environment - The RHINE study

We studied home environment exposures in relation to asthma, allergic rhinitis and atopic dermatitis among offspring of participants (parents) in the Respiratory Health in Northern Europe (RHINE) study (age ≤ 30 y). Totally 17,881 offspring from Iceland, Norway, Sweden, Denmark and Estonia were included. Home environment exposures, including dampness and mold, type of dwelling, construction year and indoor painting were registered through a questionnaire answered by parents in the first follow up (RHINE II). The parents reported ten years later with in the frame of RHINE III offspring's birth year and offspring's asthma, allergic rhinitis, atopic dermatitis. They also reported dampness and mold at home from RHINE II to RHINE III. The prevalence of offspring's asthma before 10 y, asthma after 10 y, allergic rhinitis at any age and atopic dermatitis at any age were 9.7 %, 4.3 %, 15.6 % and 17.3 %, respectively. Asthma before 10 y was related to any indoor painting at RHINE II (OR = 1.14, 95%CI (1.02, 1.29)). Asthma after 10 y was associated with dampness/mold at home (OR = 1.33-1.62) and living in the newest buildings (constructed in 1986-2001) (OR = 1.30, 95%CI (1.02, 1.66)). Allergic rhinitis was associated with living in newer buildings (constructed in 1961-2001) (OR = 1.16-1.24). Atopic dermatitis was associated with visible mold (OR = 1.35, 95%CI(1.12, 1.62)), dampness/mold at home (OR = 1.18-1.38), living in apartments (OR = 1.22, 95%CI(1.10, 1.35)) and living in newer buildings (constructed in 1961-2001) (OR = 1.14-1.25). There were dose-response effects of dampness and mold on offspring's asthma after 10 y and atopic dermatitis (20 years exposure vs. 10 years exposure). Older offspring had increased risk of developing asthma after 10 y and atopic dermatitis. In conclusion, home dampness and mold, living in apartments, living in newer buildings and indoor painting were associated with offspring's asthma or allergic diseases. Stronger health effects were found among offspring with prolonged exposure of dampness/mold.

Targeting therapeutic approaches and highlighting the potential role of nanotechnology in atopic dermatitis

Atopic dermatitis is a chronic as well as widespread skin disease which has significant influence on the life attributes of affected people and their families. Systemic immunosuppressive drugs can be utilised for effective care of disease, although they are often prescribed for rigorous disruption or disease that is complicated to manage. Therefore, topical applications of corticosteroids are considered the primary pharmacologic therapies for atopic dermatitis, and research recommends that these medications might be helpful in preventing disease flare-ups. However, topical medicine administration to deeper layers of skin is challenging because of the skin anatomic barrier that restricts deeper drug permeation, and also due to barrier function abnormalities in atopic dermatitis skin, which might result in systemic drug absorption, provoking systemic consequences. Hence, effective management of atopic dermatitis needs new, effective, safe and targeted treatments. Therefore, nanotechnology-based topical therapeutics have attracted much interest nowadays because of their tendency to increase drug diffusion and bioavailability along with enormous drug targeting potential to affected cells, and, thereby, reducing the adverse effects of medications. In this review, we mention different symptoms of atopic dermatitis, and provide an overview of the different triggering factors causing atopic dermatitis, with emphasis on its epidemiology, pathophysiology, clinical features and diagnostic, and preventive measures. This review discusses existing therapeutics for treating atopic dermatitis, and the newer approaches as well as the current classical pharmacotherapy of atopic dermatitis against new nanoparticle skin delivery systems. This review has also briefly summarised the recent patents and clinical status of therapeutic modalities for atopic dermatitis.

Potential of Tamanu (Calophyllum inophyllum) Oil for Atopic Dermatitis Treatment

Tamanu oil, derived from the nut of Calophyllum inophyllum L., has been traditionally used to treat various skin-related ailments. In recent years, this oil is increasingly gaining popularity as researchers continue to search for novel natural alternative therapies for various skin diseases. There have been a number of in vitro and in vivo studies investigating various skin-active properties of tamanu oil, and it has been proven to have potent anti-inflammatory, antioxidant, antimicrobial, analgesic, and even wound-healing abilities. These properties make tamanu oil an especially interesting candidate for the treatment of atopic dermatitis (AD). This multifaceted disease is marked by the disruption of the skin barrier function, chronic inflammation, and skin microbiome dysbiosis with limited treatment options, which is free from adverse events and inexpensive, making it desperate for a new treatment option. In this review, we examine previous in vitro and in vivo studies on AD-relevant pharmacological properties of tamanu oil in order to evaluate the potential of tamanu oil as a novel treatment option for AD.

Candidate Genes of Allergic Dermatitis Are Associated with Immune Response

Allergic dermatitis (AD) is a common and burdensome inflammatory skin disease, and diagnosis is challenging. This study was conducted to identify candidate genes for AD diagnosis and underlying molecular mechanisms. Gene expression profiles were obtained from datasets GSE121212, GSE130588, and GSE157194. Use differential analysis to identify differentially expressed genes (DEGs) between AD and control. Use enrichment analysis to identify potential molecular dysregulation mechanisms. Comprehensive least absolute shrinkage and selection operator (LASSO) logistic regression, receiver operator characteristic (ROC) curve, and logistic regression analysis are used to identify candidate genes. In addition, ssGSEA and ImmPort database were used to identify AD-related immune response abnormalities. In this study, a total of 60 common genes were identified. Enrichment analysis found that these genes are mainly involved in Th17 cell immune and complement and coagulation cascades. LASSO regression analysis identified 18 feature genes, and screened genes with AUC >0.75 were selected as candidate genes. Finally, PLA2G4D, IFI6, AGR3, IGFL1, SPRR3, ATP13A5, SERPINB13, KRT16, HAS3, and CH25H were recognized as candidate genes and may be able to diagnose AD. PLA2G4D, CH25H, and IFI6 may be risk factors for AD based on logistic analysis. Furthermore, we identified the abnormalities of immune response activation in AD patients. Interestingly, PLA2G4D, CH25H, and IFI6 had positive correlations with immune cells and signaling pathways. PLA2G4D, CH25H, and IFI6 may be candidate diagnostic genes for AD. This may be related to their promotion of abnormal immune activation, especially Th17 cell immune.

Eczema, facial erythema, and seborrheic dermatitis symptoms among young adults in China in relation to ambient air pollution, climate, and home environment

A questionnaire survey on dermal symptoms and home environment was performed in eight Chinese cities (40 279 participants). Data on city level temperature, precipitation, PM₁₀ , NO_2, and gross domestic product (GDP) per capita were collected. In total, 2.2% had eczema, 2.4% facial erythema (FE) and 2.6% seborrheic dermatitis symptoms (SD). Higher temperature was associated with eczema (OR = 1.09). Higher GDP per capita was related to less SD. Higher PM₁₀ was related to SD. Suburban living was protective for eczema (OR = 0.77) (vs. urban). Living in old buildings (built before 1991) was related to eczema (OR = 1.42). Living near heavily trafficked roads was related to FE (OR = 1.33) and SD (OR = 1.35). Having new furniture was related to all symptoms (OR = 1.26-1.47). Burning mosquito coils (OR = 1.37-1.57) and incense (OR = 1.33-1.37) were associated with eczema, FE, or SD. Presence of cockroaches and rats/mice was associated with FE or SD (OR = 1.31-1.40). Using air conditioner, daily cleaning and frequently exposing bedding to sunshine were protective (OR = 0.60-0.83). In conclusion, higher temperature, higher PM₁₀ , urban living, living near heavily trafficked roads, old buildings, new furniture, burning mosquito coils and incense, and presence of cockroaches/rats/mice increased the risk of eczema, FE, or SD. Higher GDP, air conditioner, daily cleaning, and exposing bedding to sunshine were protective.

Comorbidities and Environmental Factors Associated with Atopic Dermatitis in Children and Adults in Dermatology-Venereology in Cotonou, Benin

Introduction

The objective of this work was to document the comorbidities and environmental factors associated with atopic dermatitis (AD) in dermatology Venereology in Cotonou.

Methods

A cross-sectional, prospective, and analytical study included, from January 2016 to December 2018, in the Dermatology-Venereology Department of the National Teaching Hospital Hubert Koutoukou Maga (CNHU-HKM) of Cotonou, children and adults after free and informed consent, in whom the diagnosis of AD was retained according to the criteria of the United Kingdom Working Party. Severity was assessed using SCORAD (severity scoring of atopic dermatitis).

Results

The overall prevalence of AD was 7.7%. AD was more frequent in children (56.8% and 40.6%) and adults (59.8% and 37.4%) from urban and periurban areas (0.003 < p < 0.034). It was more frequent in children who regularly dewormed and those with complete vaccination (0.001 < p < 0.01). In 54.8% of children and 58.9% of adults, flare-ups occurred during the warm season. The main associated comorbidities were rhinitis and conjunctivitis in both children (49.7% and 36.1%, respectively) and adults (32.7% and 26.2%, respectively). The main triggering factors in children were heat (43.2%), pneumallergens (28.4%), and skin irritants (22.6%). In adults, we noted skin irritants (58.9%), heat (47.7%), and psychological factors (34.6%). In adults, the use of detergent soaps was associated with lichenified and severe AD (0.003 < p < 0.006) and that of lightening soaps with acute AD (p=0.042).

Conclusion

AD in the Dermatology-Venereology Department of the CNHU-HKM of Cotonou was associated with comorbidities. It was influenced by environmental factors related to the tropical climate and by skin irritants or allergens.

Burden of Disease, Unmet Needs in the Diagnosis and Management of Atopic Dermatitis: An Indian Expert Consensus

Background

Atopic dermatitis (AD) is a chronic inflammatory, non-communicable, and relapsing skin disease that affects all age groups. There is a dearth of literature that reports the disease burden, and epidemiology and highlights unmet needs in the diagnosis and management of AD in India.

Methods

A total of ten specialists including dermatologists, pediatric dermatologists, and pediatricians with more than ten years of experience and practicing in different parts of India served as the expert panel during the virtual meet conducted on January 24, 2021. A questionnaire comprising 32 questions on different aspects of AD management was categorized among different sections: burden of disease (five questions), age of onset and prevalence (five questions), etiology and pathogenesis (six questions), diagnosis and severity of the disease (seven questions), and treatment (nine questions). Consensus was defined when agreement was provided by ≥90% of the experts.

Results

Considering the profound impact AD has on the quality of life (QoL) of patients, the expert panel recommended patient counseling while moderate to severe cases of AD need a prompt referral to a specialist. The panel did not recommend any specific diagnostic and severity criteria as a standard due to the inherent limitations associated with every criterion. The role of environment and changing lifestyle in addition to genetic and familial risk factors for AD was also considered. The panel unanimously recommended to conduct a countrywide, multicenter survey/study to estimate the true prevalence of AD in India. Further, the experts recommended to follow proper treatment protocols and to perform longitudinal monitoring for understanding corticosteroid treatment associated side effects.

Conclusion

This guidance focuses on identifying the unmet gaps and provides practical recommendations for improving QoL, diagnosis, prognosis, and overall management of patients with AD in India.

Determinant factors of recurrence atopic dermatitis symptoms in children: A cross-sectional study

Background

Atopic dermatitis (AD) is a common health problem found in children. Understanding of the determinants of AD-related factors includes gender, family history, childbirth history, and exclusive breastfeeding.

Objective

Analyzing gender, family history, childbirth history, and exclusive breastfeeding on recurrence of AD symptoms in children.

Methods

This study employed a cross-sectional design with a purposive sampling method. The procedure for collecting data in this study included data on participant recurrence, gender, family history of atopy disease, childbirth history, and exclusive breastfeeding. The analysis used Chi-square and eta correlation test with p < 0.05.

Results

The results showed that 56.0% of male participants experienced recurrent atopic dermatitis symptoms and 56.7% of female participants did not experience recurrence (OR = 1.664; p = 0.349). It was reported that 61.3% of participants did not experience recurrent atopic symptoms with a family history of 1 atopic person and 71.4% of participants experienced recurrence with 2 atopic families (F = 2114; p = 0.349). Most participants who were delivered through cesarean delivery did not experience recurrent atopic dermatitis symptoms as much as 56.0%, while participants who had a history of spontaneous delivery mostly experienced recurrent atopic dermatitis symptoms as much as 52.9% (OR = 1.500; p = 0.467). There was a significant association between participants who received exclusive breastfeeding and recurrent atopic dermatitis symptoms (OR = 4.444; p = 0.032).

Conclusion

Recurrent of AD is influenced by exclusive breastfeeding and not influenced by gender, family history of atopy disease, and history of childbirth.

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No significant association of gender, family history, and childbirth on recurrence of atopic dermatitis symptoms.

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There is a significant association between exclusive breastfeeding and recurrent atopic dermatitis.

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Participants who experience atopic dermatitis as much as 57.1% consume exclusive breastfeeding.

Respiratory and Neurological Disease across Different Ethnic Groups Is Influenced by the Microbiome

Acute and chronic upper respiratory illnesses such as asthma, and allergic rhinitis (AR) have been linked to the presence of microorganisms in the nose. Microorganisms can exist in symbiotic or commensal relationships with the human body. However, in certain cases, opportunistic pathogens can take over, leading to altered states (dysbiosis) and causing disease. Thus, the microflora present in a host can be useful to reflect health status. The human body contains 10 trillion to 100 trillion microorganisms. Of these populations, certain pathogens have been identified to promote or undermine wellbeing. Therefore, knowledge of the microbiome is potentially helpful as a diagnostic tool for many diseases. Variations have been recognized in the types of microbes that inhabit various populations based on geography, diet, and lifestyle choices and various microbiota have been shown to modulate immune responses in allergic disease. Interestingly, the diseases affected by these changes are prevalent in certain racial or ethnic populations. These prevalent microbiome variations in these groups suggest that the presence of these microorganisms may be significantly associated with health disparities. We review current research in the search for correlations between ethnic diversity, microbiome communities in the nasal cavity and health outcomes in neurological and respiratory functions.

Vitamin D Receptor Gene Polymorphisms and Risk of Atopic Dermatitis in Chinese Han Population

BACKGROUND

Studies investigated the associations between four Vitamin D receptor (VDR) common variations and interactions of gene-environment factors and atopic dermatitis (AD) in Chinese population are few.

METHODS

In this case-control study, 400 AD patients and 400 controls were genotyped for the FokI, TaqI, BsmI and ApalI variations of VDR genes by restriction fragment length polymorphism analysis. The associations between VDR genes and AD were assessed by univariate and multivariate logistic regression. The interactions between VDR genes and some risk factors were also explored using cross-over analysis. The corresponding odds ratio (ORs) and 95% confidence intervals (CI) were also calculated.

RESULTS

The FoKI rs2228570 polymorphism was significantly associated with an increased risk of atopic dermatitis in the co-dominant model (OR=2.93, 95% CI: 1.78-4.82. P=0.000), recessive model (OR=2.67, 95% CI: 1.68-4.26, P=0.000) and dominant model (OR=1.38, 95% CI: 1.04-1.84, P=0.028), and allele model. No significant associations were found among TaqI, BsmI and ApalI polymorphism and AD. The C-A-T-C and C-G-T-T haplotypes significantly increased the risk of atopic dermatitis. For rs2228570, the increased effects were more evident in the subgroups of age ≤8-month, cow milk and mixed, and keeping pet. Interactions between rs2228570 gene polymorphism and family history, age >8, and keeping pet increased the AD risk. The rs2228570 C allele decreased the relative mRNA expression.

CONCLUSION

The FokI rs2228570 C allele of VDR gene could be a risk candidate gene for AD. Interactions between FokI polymorphism and family history and some behaviors may increase the risk of AD.

Associations between maternal and environmental exposures on atopic disease in the offspring of mothers with asthma

Background and Objective

Available data on the impact of perinatal and environmental factors on atopic diseases in the offspring are sparse and conflicting. We, therefore, investigated the impact of these factors on the risk of atopic diseases in the offspring of women with asthma.

Methods

Pregnant women referred to give birth at Copenhagen University Hospital‐Hvidovre, Denmark, have since 2007 been invited to participate in the Management of Asthma during Pregnancy program. Women with diagnosed asthma, currently prescribed asthma medication, first visit to the respiratory out‐patient clinic within the first 18 weeks of pregnancy that completed an online questionnaire about atopic diseases in their child were included in the current study.

Results

Five hundred and seventy‐one pregnancies were included. Among the off‐spring, 113 children (21%) had doctor‐diagnosed asthma, 178 (31%) atopic dermatitis (AD), and 55 (32%) both AD and doctor‐diagnosed asthma. AD in the offspring was associated with having a dog at home (odds ratio [OR], 2.56; 95% confidence interval [CI], [1.40–4.67], p = .002), whereas having a cat at home was associated with a higher risk of asthma in the offspring (OR, 2.16; 95% CI, [1.14–4.11], p = .02). The associations remained significant after adjusting for maternal age, smoking status, allergy, treatment with inhaled corticosteroids, forced expiratory volume in 1 s less than 80% predicted, uncontrolled asthma, and history of pre‐pregnancy asthma exacerbations. No association was found between gestational weight gain (GWG) in first trimester and total GWG and atopic disease in the offspring.

Conclusion

Having pets at home is associated with AD and asthma in the offspring of mothers with asthma.

Targeted resequencing showing novel common and rare genetic variants increases the risk of asthma in the Chinese Han population

BACKGROUND

Although studies have identified hundreds of genetic variants associated with asthma risk, a large fraction of heritability remains unexplained, especially in Chinese individuals.

METHODS

To identify genetic risk factors for asthma in a Han Chinese population, 211 asthma-related genes were first selected based on database searches. The genes were then sequenced for subjects in a Discovery Cohort (284 asthma patients and 205 older healthy controls) using targeted next-generation sequencing. Bioinformatics analysis and statistical association analyses were performed to reveal the associations between rare/common variants and asthma, respectively. The identified common risk variants underwent a validation analysis using a Replication Cohort (664 patients and 650 controls).

RESULTS

First, we identified 18 potentially functional rare loss-of-function (LOF) variants in 21/284 (7.4%) of the asthma cases. Second, using burden tests, we found that the asthma group had nominally significant (p < 0.05) burdens of rare nonsynonymous variants in 10 genes. Third, 23 common single-nucleotide polymorphisms were associated with the risk of asthma, 7/23 (30.4%) and 9/23 (39.1%) of which were modestly significant (p < 9.1 × 10^-4 ) in the Replication Cohort and Combined Cohort, respectively. According to our cumulative risk model involving the modestly associated alleles, middle- and high-risk subjects had a 2.0-fold (95% CI: 1.621-2.423, p = 2.624 × 10^-11 ) and 6.0-fold (95% CI: 3.623-10.156, p = 7.086 × 10^-12 ) increased risk of asthma, respectively, compared with low-risk subjects.

CONCLUSION

This study revealed novel rare and common genetic risk factors for asthma, and provided a cumulative risk model for asthma risk prediction and stratification in Han Chinese individuals.

Association between maternal vegetable intake during pregnancy and allergy in offspring: Japan Environment and Children's Study

The association between maternal diet during pregnancy and allergy in offspring remains contentious. Here, we examined the association between maternal intake of vegetables and related nutrients during pregnancy and allergic diseases in offspring at one year of age. A cohort of 80,270 pregnant women enrolled in the Japan Environment and Children's Study were asked to respond to a food frequency questionnaire during pregnancy and the International Study of Asthma and Allergies in Childhood questionnaire at one year postpartum. The women were categorized into quintiles according to the energy-adjusted maternal intake of vegetables and related nutrients. Using the categorizations as exposure variables, the adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were determined for the allergic outcomes, including asthma, wheeze, atopic dermatitis, eczema, and food allergy, in the offspring per quintile at one year of age. Of the 80,270 participants, 2,027 (2.5%), 15,617 (19.6%), 3,477 (4.3%), 14,929 (18.7%), 13,801 (17.2%), and 25,028 (31.3%) children experienced asthma, wheeze, atopic dermatitis, eczema, food allergy, and some form of allergic disease, respectively. The aORs of each quintile of maternal vegetable intake for all allergic outcomes were close to 1.0 compared to the lowest quintile. The lowest aOR was found in the association of maternal cruciferous vegetable intake with asthma (aOR: 0.82, 95% CI: 0.70-0.96) and highest was found in the association of maternal total vegetable intake with atopic dermatitis (aOR: 1.17, 95% CI: 1.04-1.31). The risk of allergic outcomes for the various nutrients related to vegetable consumption was close to 1.0. The maternal intake of vegetables and various related nutrients during pregnancy had little or no association with any of the allergic outcomes, including asthma, wheezing, atopic dermatitis, eczema, and food allergy, in offspring at one year.

Risk Factors in Outpatients with Dermatitis and Eczema in Tertiary Hospitals of China Who Have Clinically Suspected Bacterial Infection

Skin bacterial infections are often observed in eczema patients, but the risk factors are not fully understood. The current study evaluated the prevalence of clinically suspected bacterial infection and its associated risk factors. Moreover, we investigated the practice of skin infection diagnosis in China. A hospital-based, multicenter, cross-sectional epidemiologic survey of bacterial infection was performed in a total of 6208 outpatients diagnosed with dermatitis and eczema from 39 tertiary hospitals of 15 provinces and municipalities in China. All patients completed a specific questionnaire regarding their demographic characteristics, disease duration, distribution of lesions, severity of itching, and medical history. Univariate analysis and multivariate analysis were used to evaluate risk factors associated with bacterial infection in patients with different types of eczema. The prevalence of clinically suspected bacterial infection was 47.0% in patients with eczema. Compared to atopic dermatitis, widespread eczema (OR = 1.50, P < 0.001) and other eczema (OR = 1.42, P < 0.001) were more likely to suffer bacterial infection. The itching grade was positively associated with the infection (OR = 2.11, 7.04, and 12.3 in patients with mild, moderate, and severe itching, respectively; P < 0.001). Lesion distribution in the cubital fossa, popliteal fossa, ear, shoulder and back, axillary, foot, and pudendum was positively associated with bacterial infection (all OR > 1.0, P < 0.05). In contrast, the face and abdomen were reversely associated with bacterial infection (OR < 1.0, P < 0.005). History of asthma, allergic rhinitis, allergic conjunctivitis, atopic dermatitis, infantile eczema, and flexion dermatitis was positively associated with bacterial infection (all OR > 1.0, P < 0.005), while the history of dry skin was reversely associated with bacterial infection (OR = 0.76, 95% CI: 0.64-0.90; P = 0.002). Patients with eczema were easily infected with bacteria. Widespread eczema and other eczema were more likely to have bacterial infection than atopic dermatitis. The high rate of infection may attribute to the lack of corresponding bacterial detection, suggesting the need of guideline development in China to prevent overuse of topical antibiotics.

The risk factors for occupational contact dermatitis among workers in a medium density fiberboard furniture factory in Eastern Thailand

The aim of this study was to determine the occupational exposure to formaldehyde on the medium-density fiberboard (MDF) dust and allergic contact dermatitis among the workers at a furniture factory. Data were collected from 439 subjects using questionnaires and patch testing to evaluate allergic contact dermatitis resulting from formaldehyde on wood dust exposure in the workplace. The geometric mean concentration of formaldehyde on MDF dust that the workers in the production department were exposed to was 2.07 ppm (GSD 4.54). Patch test results revealed that some subjects developed allergy to various substances, including epoxy resin (16.7%) and formaldehyde (5.6%). The odds ratios (95% CI) for contact dermatitis were 3.6 (1.7-7.3) among those with a history of metal allergy, 1.8 (0.6-5.2) whose family members having a history of allergic contact dermatitis. Exposure to MDF dust in the workplace should be reduced, as the current levels of exposure exceed the permissible OSHA standard.

Genetic predisposition and environmental factors associated with the development of atopic dermatitis in infancy: a prospective birth cohort study

The influence of environmental factors on atopic dermatitis (AD) has been investigated in many cross-sectional studies. It remains however unclear if they could influence AD development early in life. This prospective birth cohort study aimed to monitor aspects of family lifestyle and child's nutrition within a Caucasian population and to assess its association with AD development over the first 2 years of life. Genetic predisposition was evaluated based on family history and profilaggrin genotyping. Of 149 included children, 36 developed AD. Infants with a family history of atopy developed AD 2.6 times more frequently (30 of 97) than infants without atopic predisposition (6 of 52). Genotyping was carried out on 50% of the children included. Profilaggrin mutations (R501X, 2282del4, R2447X, and S3247X) were infrequent in our population. Lower incidence of AD was observed in infants exposed to a damp housing environment, lower household income, and smoking mothers with a higher but not with a lower education level.Conclusion: Family history of atopy was a significant risk factor for AD regardless of the most common, currently defined, FLG mutations. Humidity at home and passive smoking seem associated with AD development in infancy. What is Known: • Atopic dermatitis (AD) is associated with mutations in various genes of the immune system and the epidermal barrier complex in particular filaggrin (FLG) mutation. • Inherited factors alone cannot explain the rising AD; environmental factors are therefore likely to play a decisive role in this rise but the exact role that these factors may play in increasing AD risk in infancy remains unclear. Moreover, the relationship between environmental factors and AD has been the focus of mostly cross-sectional studies and not prospective studies. What is New: • This prospective birth cohort study demonstrates that family history of atopy is a significant risk factor for AD regardless of the most common, currently defined, FLG mutations. • A lower incidence of AD was observed in infants exposed to a moist housing environment, lower household income, and smoking of mothers with a higher but not with a lower education level.

The Role of Genetics, the Environment, and Epigenetics in Atopic Dermatitis

Atopic Dermatitis (AD) is a common inflammatory disease with a genetic background. The prevalence of AD has been increasing in many countries. AD patients often have manifestations of pruritus, generalized skin dryness, and eczematous lesions. The pathogenesis of AD is complicated. The impaired skin barrier and immune imbalance play significant roles in the development of AD. Environmental factors such as allergens and pollutants are associated with the increasing prevalence. Many genetic and environmental factors induce a skin barrier deficiency, and this can lead to immune imbalance, which exacerbates the impaired skin barrier to form a vicious cycle (outside-inside-outside view). Genetic studies find many gene mutations and genetic variants, such as filaggrin mutations, which may directly induce the deficiency of the skin barrier and immune system. Epigenetic studies provide a connection between the relationship of an impaired skin barrier and immune and environmental factors, such as tobacco exposure, pollutants, microbes, and diet and nutrients. AD is a multigene disease, and thus there are many targets for regulation of expression of these genes which may contribute to the pathogenesis of AD. However, the epigenetic regulation of environmental factors in AD pathogenesis still needs to be further researched.

Trends in Atopic Dermatitis-From Standard Pharmacotherapy to Novel Drug Delivery Systems

Atopic dermatitis (AD) is a predominant and deteriorating chronic inflammation of the skin, categorized by robust burning and eczematous lacerations in diverse portions of the body. AD affects about 20% of both offspring and adults worldwide. The pathophysiology of AD combines environmental, hereditary, and immunological aspects, together with skin barrier dysfunction. The procedures used to prevent the disease are the everyday usage of creams to support the restoration of the epidermal barrier. The classical treatments include the use of topical corticosteroids as a first-line therapy, but also calcineurin inhibitors, antihistamines, antibiotics, phototherapy, and also immunosuppressant drugs in severe cases of AD. Topical drug delivery to deeper skin layers is a difficult task due to the skin anatomic barrier, which limits deeper penetration of drugs. Groundbreaking drug delivery systems, based on nanoparticles (NPs), have received much attention due to their ability to improve solubility, bioavailability, diffusion, targeting to specific types of cells, and limiting the secondary effects of the drugs employed in the treatment of AD. Even so, additional studies are still required to recognize the toxicological characteristics and long-term safety of NPs. This review discusses the current classical pharmacotherapy of AD against new nanoparticle skin delivery systems and their toxicologic risks.

Asthma, allergic rhinitis and eczema among parents of preschool children in relation to climate, and dampness and mold in dwellings in China

The main aim was to study associations between asthma, allergic rhinitis and eczema among adults across China and dampness and mold at home. Young adults (N = 40,279) in eight cities in China answered a questionnaire in 2010-2012 (response rate 75.0%). Data on asthma, allergic rhinitis, eczema and the home environment was assessed by the questionnaire. Climate data was obtained from China Meteorological Administration and the website of Weather Underground. Health associations were analyzed by two-level logistic regression models, adjusting for covariates. Totally 1.6% had asthma, 6.6% allergic rhinitis and 2.2% eczema. Mold odor was associated with asthma (OR = 1.90) and allergic rhinitis (OR = 1.25-1.44). Window pane condensation in winter was associated with asthma (OR = 1.39), allergic rhinitis (OR = 1.26-1.58) and eczema (OR = 1.36-1.77). Presence of mold spots or damp stains was related to asthma (OR = 1.58-2.49), allergic rhinitis (OR = 1.35-1.76) and eczema (OR = 1.47-1.70). Water damage was related to asthma (OR = 1.69-1.82), allergic rhinitis (OR = 1.40-1.45) and eczema (OR = 1.44-1.96). Damp bed clothing was related to asthma (OR = 1.23), allergic rhinitis (OR = 1.23) and eczema (OR = 1.35). A higher dampness score was associated with increased odds ratios for diseases. Those living in older buildings had more asthma (OR = 1.39-1.76) and allergic rhinitis (OR = 1.16-1.21). Those living in suburban or rural areas had less asthma, allergic rhinitis and eczema as compared to those living in urban areas (OR values from 0.24 to 0.66). Stronger health associations with dampness and mold were found in southern China and in newer buildings (constructed after 2005). In conclusion, dampness and mold at home can be risk factors for asthma, allergic rhinitis and eczema among adults in China. Living in older buildings can be risk factors for asthma or allergic rhinitis while living in less urbanized areas can be protective.

Factors Associated with Atopic Dermatitis and Allergic Rhinitis among Residents of Two Municipal Areas in South Korea

Background and Objectives: The growing burden and deleterious health consequences of allergic diseases, especially of allergic rhinitis (AR) and atopic dermatitis (AD), in developed countries remains an important public health issue. The current study aimed to assess the prevalence and to identify the risk factors of atopic dermatitis and allergic rhinitis among residents of Pohang-Si and Yeongdeok-Gun, two municipal areas in South Korea. Materials and Methods: A cross-sectional study was conducted in both municipal areas between 12 November and 13 December 2017. A total of 302 subjects were recruited from 100 households (25 apartments and 25 houses in each municipality), by system extraction according to district code numbers. Data were collected using International Study of Asthma and Allergies in Childhood (ISAAC) Standard Questionnaires for children and a health questionnaire for adults. Risk factors were identified by multivariate logistic regression analysis. Results: Of the 302 study participants, 12.9% and 25.5% had AD and AR, respectively. The significant factors associated with AD by multivariate logistic regression analysis were age ≥19 years (aOR (adjusted odds ratio) 6.9; 95% CI (confidence interval) (2.9–16.37)), residence in Pohang-Si (aOR 2.5; 95% CI (1.18–5.53)), and family history of allergic disease (aOR 2.3; 95% CI (1.09–4.9)). Similarly, the significant factors associated with AR were male gender (aOR 2.3; 95% CI (1.24–4.42)), age ≥19 years (aOR 4.4; 95% CI (2.28–8.48)), residence in Pohang-Si (aOR 2.8; 95% CI (1.51–5.37)), and family history of allergic disease (aOR 6.7; 95% CI (3.50–12.82)). Conclusion: The present study shows that age ≥19 years, residence in Pohang-Si, and family history of allergic disease are risk factors for AD and AR, and that, additionally, male gender is a risk factor of AR. Understanding the risk factors of allergic diseases can aid the design and implementation of evidence-specific strategies to reduce the long-standing problems associated with allergic disease.

Relation Between Attention-Deficit Hyperactivity Disorder and IgE-Dependent Allergy in Pediatric Patients

Food allergy is a common condition in children and adolescent, remitting with time. Few clinical studies have emphasized the link between food allergies and psychosocial conditions, suggesting a profound impact of atopic diseases on the development of attention-deficit hyperactivity disorder (ADHD) in children. The objective of this study was to compile and assess available studies on the comorbidity or causality between ADHD and atopic food allergy in children. We discuss epidemiology, interrelated mechanisms, and potential dietary interventions in the management of children with ADHD.