Is the atopic march related to confounding by genetics and early-life environment? A systematic review of sibship and twin data

Lifestyle Changes and Industrialization in the Development of Allergic Diseases

PURPOSE OF REVIEW

Modernization and Westernization in industrialized and developing nations is associated with a substantial increase in chronic noncommunicable diseases. This transformation has far-reaching effects on lifestyles, impacting areas such as economics, politics, social life, and culture, all of which, in turn, have diverse influences on public health. Loss of contact with nature, alternations in the microbiota, processed food consumption, exposure to environmental pollutants including chemicals, increased stress and decreased physical activity jointly result in increases in the frequency of inflammatory disorders including allergies and many autoimmune and neuropsychiatric diseases. This review aims to investigate the relationship between Western lifestyle and inflammatory disorders.

RECENT FINDINGS

Several hypotheses have been put forth trying to explain the observed increases in these diseases, such as 'Hygiene Hypothesis', 'Old Friends', and 'Biodiversity and Dysbiosis'. The recently introduced 'Epithelial Barrier Theory' incorporates these former hypotheses and suggests that toxic substances in cleaning agents, laundry and dishwasher detergents, shampoos, toothpastes, as well as microplastic, packaged food and air pollution damage the epithelium of our skin, lungs and gastrointestinal system. Epithelial barrier disruption leads to decreased biodiversity of the microbiome and the development of opportunistic pathogen colonization, which upon interaction with the immune system, initiates local and systemic inflammation. Gaining a deeper comprehension of the interplay between the environment, microbiome and the immune system provides the data to assist with legally regulating the usage of toxic substances, to enable nontoxic alternatives and to mitigate these environmental challenges essential for fostering a harmonious and healthy global environment.

Skin, gut, and lung barrier: Physiological interface and target of intervention for preventing and treating allergic diseases

The epithelial barriers of the skin, gut, and respiratory tract are critical interfaces between the environment and the host, and they orchestrate both homeostatic and pathogenic immune responses. The mechanisms underlying epithelial barrier dysfunction in allergic and inflammatory conditions, such as atopic dermatitis, food allergy, eosinophilic oesophagitis, allergic rhinitis, chronic rhinosinusitis, and asthma, are complex and influenced by the exposome, microbiome, individual genetics, and epigenetics. Here, we review the role of the epithelial barriers of the skin, digestive tract, and airways in maintaining homeostasis, how they influence the occurrence and progression of allergic and inflammatory conditions, how current treatments target the epithelium to improve symptoms of these disorders, and what the unmet needs are in the identification and treatment of epithelial disorders.

Effectiveness of sublingual immunotherapy in pediatric cedar pollinosis: A real-world database study

BACKGROUND

Pediatric allergic rhinitis (AR), including cedar pollinosis (CP), is increasing in Japan. We investigated the effects of sublingual immunotherapy (SLIT), which has limited studies of its effectiveness in real-world settings, on children with CP.

METHODS

This retrospective cohort study used a claim database in 2018-2021. Children aged ≤15 years with CP records in 2019 were eligible and were followed up through 2021. We included 2962 CP children undergoing SLIT and 547 who were not. The medication score was used to evaluate SLIT effectiveness in the cedar pollen dispersal season each year. Adverse events and the occurrence of allergic diseases were also evaluated.

RESULTS

Medication score was higher in the SLIT group during the index period but lower in 2021 compared to the non-SLIT group (mean ± standard deviation: 5.17 ± 2.39 and 4.74 ± 2.38 in 2019, 3.13 ± 2.30 and 3.55 ± 2.48 in 2021, respectively). The adjusted mean difference between groups from 2019 to 2021 was -0.62 (95% confidence interval: -0.86 to -0.39, p < .0001), and the medication score was reduced in the SLIT group (risk ratio: 1.2: 1.1 to 1.3). The occurrence of adverse events involving abdominal disorders (adjusted odds ratio [aOR]: 0.64: 0.51 to 0.81), asthma exacerbation (aOR: 0.37: 0.24 to 0.57), and allergic diseases involving hay fever unrelated to CP (aOR: 0.60: 0.45 to 0.80) or asthma (aOR: 0.71: 0.58 to 0.86) was lower in the SLIT group.

CONCLUSION

In children with CP, SLIT is effective, well tolerated, and could decrease the occurrence of other allergic diseases.

Association of serum CD14 level and functional polymorphism C-159T in the promoter region of CD14 gene with allergic rhinitis

Allergic rhinitis (AR) is an inflammatory disease of the upper respiratory tract affecting a significant number of the world's population. It occurs as an IgE-mediated immune response of the nasal mucosa to inhaled allergens. The human Cluster of Differentiation 14 (CD14) is a glycosyl-phosphatidylinositol-anchored molecule expressed on the surface of monocytes and macrophages and functions as a receptor to lipopolysaccharides and inhaled endotoxins that may stimulate interleukins production by antigen-presenting cells. Consequently, CD14 plays a substantial role in allergic diseases and may become one of their etiological causes. This study aimed to determine the association between C-159T polymorphism in the CD14 gene promoter region and serum CD14 levels and the risk of Allergic rhinitis Egyptian patients and to test the validity of serum CD14 level measurement in predicting AR. This case-control study included 45 patients with AR referred to Allergy and Immunology Unit, Zagazig University Hospital, Zagazig, Egypt, and 45 healthy subjects as controls. Serum CD14 levels were measured by ELISA. The polymerase chain reaction-restriction fragment length polymorphism technique was used to detect C-159T gene polymorphism in the CD14 promoter region. There was a significant association between CD14 serum levels and AR incidence (P < 0.001), with patients having higher serum CD14 levels than controls. In addition, a significant association (P < 0.001) was detected between serum CD14 levels and the severity of AR, as well as elevated serum CD14 levels in severe and the most severe cases. On the molecular level, there was a statistically significant relationship between patients and the control group regarding the CD14 genotype (P < 0.001), where CT and TT genotypes and T allele were primarily associated with the cases group, indicating that the risk of AR was significantly associated with the inheritance of the TT genotype. Additionally, a statistically significant association was found between the severity of AR and CD14 genotype (P < 0.001), where TT genotypes were mainly associated with severe and the most severe cases. In the studied groups, there was a statistically significant difference (P < 0.05) between the CD14 genotype and serum CD14 levels, with TT genotypes being associated with higher CD14 levels. The results obtained in this study revealed that serum CD14 level is a potential biomarker for the diagnosis of AR and, at the genetic level, a potential predictor of disease.

Disease modification in inflammatory skin disorders: opportunities and challenges

Progress in understanding of the mechanisms underlying chronic inflammatory skin disorders, such as atopic dermatitis and psoriasis vulgaris, has led to new treatment options with the primary goal of alleviating symptoms. In addition, this knowledge has the potential to inform on new strategies aimed at inducing deep and therapy-free remission, that is, disease modification, potentially impacting on associated comorbidities. However, to reach this goal, key areas require further exploration, including the definitions of disease modification and disease activity index, further understanding of disease mechanisms and systemic spillover effects, potential windows of opportunity, biomarkers for patient stratification and successful intervention, as well as appropriate study design. This Perspective article assesses the opportunities and challenges in the discovery and development of disease-modifying therapies for chronic inflammatory skin disorders.

Subcutaneous birch pollen allergen immunotherapy with a depigmented polymerized extract shows only sustained and long-term efficacy in a subgroup of monosensitized adults and adolescents with allergic rhinitis

Background

Allergen immunotherapy (AIT) is an approved treatment for seasonal respiratory allergic diseases. A depigmented polymerized birch pollen extract for subcutaneous allergen immunotherapy (SCIT) has been demonstrated to be efficacious and safe in patients allergic to birch pollen and its homologous group.

Objective

To determine whether SCIT with a birch pollen formulation (5000 depigmented polymerized (DPP) units/mL) shows sustained and long-term efficacy in adults and adolescents with birch-pollen induced allergic rhinitis with or without intermittent asthma.

Methods

A multicentre (n = 66), double-blind, placebo-controlled Phase III clinical trial was performed in the Czech Republic, Finland, Germany, Latvia, Lithuania, Poland and Russia. Participants were randomized 2:1 to active treatment (birch 5000 DPP/ml) or placebo for three years of SCIT and followed up for two treatment-free years. The primary efficacy endpoint was the EAACI's combined symptom and medication score for rhinoconjunctivitis (CSMSEAACI).

Results

A total of 973 participants were screened and 649 were randomized (active treatment: n = 434; placebo: n = 215). The intention-to-treat analysis of the CSMSEAACI in the overall study population did not demonstrate statistically significant differences in years 1, 2 and 3. In a post-hoc analysis, among the subgroup of patients monosensitized to birch pollen allergen only (n = 200), we observed a statistically significant difference (active treatment vs. placebo) in the CSMSEAACI in year 2, 3 and 5. The AIT's safety profile was good.

Conclusions

SCIT with a depigmented polymerized birch pollen extract was safe. Sustained and long-term efficacy in years 2, 3 and 5 in monosensitized patients, but not in polysensitized patients was demonstrated.(EudraCT 2012-000414-11).

Atopic Dermatitis Mediates the Association Between an IL4RA Variant and Food Allergy in School-Aged Children

BACKGROUND

Atopic dermatitis (AD) and food allergy (FA) may share genetic risk factors. It is unknown whether genetic factors directly cause FA or are mediated through AD, as the dual-allergen hypothesis suggests.

OBJECTIVE

To test the hypothesis that AD mediates the relationship between an IL-4 receptor alpha chain gene (IL4RA) variant, the human IL-4 receptor alpha chain protein-R576 polymorphism, and FA.

METHODS

A total of 433 children with asthma enrolled in the School Inner-City Asthma Study underwent genotyping for the IL4RA⁵⁷⁶ allele. Surveys were administered to determine FA, AD, and associated allergic responses. Mediation analysis was performed adjusting for race and ethnicity, age, sex, and household income. Multivariate models were used to determine the association between genotype and FA severity.

RESULTS

AD was reported in 193 (45%) and FA in 80 children (19%). Each risk allele increased odds of AD 1.39-fold ([1.03-1.87], P = .03), and AD increased odds of FA 3.67-fold ([2.05- 6.57], P < .01). There was an indirect effect of genotype, mediated by AD, predicting FA; each risk allele increased the odds of FA by 1.13 (odds ratio [95% CI], Q/R = 1.13 [1.02-1.24], R/R = 1.28 [1.04-1.51]; P < .01). Each risk allele increased the odds of severe FA symptoms 2.68-fold ([1.26-5.71], P = .01).

CONCLUSIONS

In a cohort of children with asthma, AD is part of the causal pathway between an IL4RA variant and FA. This variant is associated with increased risk of severe FA reactions. Addressing AD in children with an IL4RA polymorphism may modulate the risk of FA.

Polymorphisms and AR: A Systematic Review and Meta-Analyses

Background: Allergic rhinitis (AR) is an especially common disorder associated with both environmental and genetic factors, and a lot of researchers have attempted to find polymorphisms which predisposed to the disease. We conducted a meta-analysis of the most frequently researched polymorphisms to find those genes which may be susceptible to AR and then may be of value in diagnosis.

Methods: Pubmed and China National Knowledge Infrastructure (CNKI) databases were searched to screen out eligible studies focusing on the correlation between polymorphisms and AR susceptibility, and then polymorphisms cited in at least 3 studies were selected.

Results: The 142 papers originally selected cited 78 genes. Twelve genes (coinciding with 23 polymorphisms) were reported in more than three papers. Twenty-three polymorphisms were involved in the meta-analysis. Among the 23 polymorphisms, only 4 were found to be related to the risk of AR: IL-13 rs20541, CTLA-4 rs11571302, IL-4R RS1801275 and ACE (I/D). The remaining 19 of the 23 polymorphisms were not associated with AR.

Conclusion: We found polymorphisms that could be used for AR diagnosing and those that were unrelated to AR. This may be the first step in detecting polymorphic combinations susceptible to AR (IL-13 RS20541, CTLA-4 RS11571302, IL-4R RS1801275 and ACE (I/D). In addition, our results may improve AR diagnosis and contribute to the intensive study of AR.

Unmet Medical Needs in Chronic, Non-communicable Inflammatory Skin Diseases

An estimated 20-25% of the population is affected by chronic, non-communicable inflammatory skin diseases. Chronic skin inflammation has many causes. Among the most frequent chronic inflammatory skin diseases are atopic dermatitis, psoriasis, urticaria, lichen planus, and hidradenitis suppurativa, driven by a complex interplay of genetics and environmental factors. Autoimmunity is another important cause of chronic skin inflammation. The autoimmune response may be mainly T cell driven, such as in alopecia areata or vitiligo, or B cell driven in chronic spontaneous urticaria, pemphigus and pemphigoid diseases. Rare causes of chronic skin inflammation are autoinflammatory diseases, or rheumatic diseases, such as cutaneous lupus erythematosus or dermatomyositis. Whilst we have seen a significant improvement in diagnosis and treatment, several challenges remain. Especially for rarer causes of chronic skin inflammation, early diagnosis is often missed because of low awareness and lack of diagnostics. Systemic immunosuppression is the treatment of choice for almost all of these diseases. Adverse events due to immunosuppression, insufficient therapeutic responses and relapses remain a challenge. For atopic dermatitis and psoriasis, a broad spectrum of innovative treatments has been developed. However, treatment responses cannot be predicted so far. Hence, development of (bio)markers allowing selection of specific medications for individual patients is needed. Given the encouraging developments during the past years, we envision that many of these challenges in the diagnosis and treatment of chronic inflammatory skin diseases will be thoroughly addressed in the future.

Prevalence of infantile wheezing and eczema in a metropolitan city in Japan: A complete census survey

Infantile wheezing and eczema are associated with the subsequent onset of asthma and other atopic diseases. However, there are no large population-based surveys on infantile allergic symptoms in Japan. The objective of the study was to determine the prevalence of wheezing and asthma in infants in Nagoya, Japan. This population-based cross-sectional study was performed in the metropolitan city of Nagoya, Japan. We surveyed parents to ascertain the prevalence of wheezing and eczema in infants who attended group health checkups at 3, 18, and 36 months of age. Their parents completed modified questionnaires from the International Study of Asthma and Allergies in Childhood. More than 90% of the approximately 40,000 children in each study group living in the target area were included in the survey. The prevalence of wheezing was 8%, 17%, and 13% at 3, 18, and 36 months, respectively, and was characterized by birth season. The prevalence of eczema was 24%, 30%, and 31%, at 3, 18, and 36 months, respectively. Participants born in autumn and winter had a higher incidence of eczema in each age group. Three-quarters of the children had a parental history of allergic conditions. Parental allergic diseases and male gender are risk factors for wheezing and eczema in children. This survey had a high response rate and covered almost the entire population of the target age groups in a large city. We believe that the results of this study, therefore, provide a much higher level of confidence regarding the prevalence of allergies in infants in Japan than that in previous studies with limited cohorts.

Current Insights into Atopic March

The incidence of allergic diseases is increasing, and research on their epidemiology, pathophysiology, and the prevention of onset is urgently needed. The onset of allergic disease begins in infancy with atopic dermatitis and food allergy and develops into allergic asthma and allergic rhinitis in childhood; the process is defined as “atopic march”. Atopic march is caused by multiple immunological pathways, including allergen exposure, environmental pollutants, skin barrier dysfunction, type 2 inflammation, and oxidative stress, which promote the progression of atopic march. Using recent evidence, herein, we explain the involvement of allergic inflammatory conditions and oxidative stress in the process of atopic march, its epidemiology, and methods for prevention of onset.

Association between ADRB2 regulatory region polymorphisms and susceptibility to childhood asthma

OBJECTIVES

To study the association of β2-drenergic receptor (ADRB2) regulatory region single nucleotides polymorphism (SNP)/haplotypes at rs11168070, rs17108803, rs2053044, rs12654778, rs11959427, and rs2895795 loci with childhood asthma.

METHODS

A total of 143 children with asthma who attended the hospital from October 2016 to October 2020 were enrolled as the asthma group, among whom 61 children had mild symptoms (mild group) and 82 children had moderate-to-severe symptoms (moderate-to-severe group). A total of 137 healthy children were enrolled as the control group. Peripheral venous blood samples were collected from the two groups. The SNaPshot SNP technique was used to analyze the SNP and haplotypes of the ADRB2 regulatory region at rs11168070, rs17108803, rs2053044, rs12654778, rs11959427, and rs2895795 loci in all children. The asthma group and the control group were compared in terms of the association of ADRB2 regulatory region SNP and haplotypes at the above six loci with susceptibility to asthma and severity of asthma.

RESULTS

Polymorphisms were observed in the ADRB2 regulation region at the above six loci in both the asthma group and the control group, with significant differences between the two groups in the distribution of genotype and allele frequencies at rs2895795 (-1429T /A), rs2053044(-1023G/A), and rs12654778 (-654G/A) loci (P<0.05). Linkage disequilibrium of SNP was observed at the six loci of the ADRB2 regulatory region.The haplotypes of TATGCT, TATGGC, and AGTGCT were associated with susceptibility to childhood asthma, among which TATGCT and TATGGC were risk factors for childhood asthma (OR=1.792 and 1.946 respectively, P<0.05), while AGTGCT was a protective factor (OR=0.523, P<0.05).

CONCLUSIONS

SNP/haplotype of the ADRB2 regulatory region is associated with the susceptibility to childhood asthma. The haplotypes of TATGCT and TATGGC formed by such SNP/haplotype are risk factors for childhood asthma, while AGTGCT is a protective factor.

What are the highest yielding search strategy terms for systematic reviews in atopic dermatitis? A systematic review

The impact of search strategies on systematic reviews (SR) of atopic dermatitis (AD) is unknown. The purpose of this review was to evaluate search strategies used in SR of AD and their impact on the frequency of manuscripts identified. MEDLINE and EMBASE were searched for SR related to AD. Simulations were performed by running combinations of search terms in MEDLINE and EMBASE. Overall, 250 SR met inclusion criteria, of which 225 specified search strategies. SR using 5-6 terms (20.0% to 12.1%) or ≥ 7 (40.0% to 18.8%) terms decreased, whereas SR using 3-4 terms numerically increased (18.8% to 30.2%) and 1-2 terms remained similar (37.5% to 38.9%) from 1999-2009 to 2015-2019. The most commonly searched terms were "atopic dermatitis" (n = 166), followed by "eczema" (n = 156), "dermatitis atopic'" (n = 81), "atopic eczema" (n = 74), "neurodermatitis" (n = 59), "Besniers prurigo" (n = 29), "infantile eczema" (n = 27), and "childhood eczema" (n = 19). Simulations revealed that "eczema" and "atopic dermatitis" yielded the most hits. The number of search terms that maximized hits in MEDLINE and EMBASE was 5 and 4, respectively. Search strategies for AD were heterogeneous, with high proportions of search strategies providing few search hits. Future studies should use standardized and optimized search terms.

Unmet needs in atopic dermatitis management: an expert consensus

INTRODUCTION

Atopic dermatitis (AD) has substantial negative impact on patients' quality of life. Although considerable advances have been made in understanding the pathogenesis and its treatment, there is still limited transfer of this knowledge into daily management. Aiming to identify unmet needs in clinical management of patients with AD, we used a Delphi consensus process.

METHODS

A set of statements regarding diagnosis, management, prognosis, and treatment was identified by five experts (Steering Committee). Then, the Steering Committee and a second group of four clinicians were involved in a Delphi process. Lastly, agreement was assessed in a larger panel of Italian clinicians.

RESULTS

Overall, 37 clinicians participated to the process. 17 statements reached strong agreement and 2 reached weak agreement.

CONCLUSIONS

In general, the statements reflected the need for accurate and effective diagnostic criteria to support clinical experience, especially in the atypical forms of AD. Moreover, prognostic criteria are needed to predict the duration of adult-onset AD. The identification of biomarkers was considered to be useful for clinical management of AD at all stages of disease. Lastly, greater emphasis should be placed on patient education and development of effective tools that can aid informing patients about their disease and its treatment.

Dysregulation of the epithelial barrier by environmental and other exogenous factors

The “epithelial barrier hypothesis” proposes that the exposure to various epithelial barrier–damaging agents linked to industrialization and urbanization underlies the increase in allergic diseases. The epithelial barrier constitutes the first line of physical, chemical, and immunological defense against environmental factors. Recent reports have shown that industrial products disrupt the epithelial barriers. Innate and adaptive immune responses play an important role in epithelial barrier damage. In addition, recent studies suggest that epithelial barrier dysfunction plays an essential role in the pathogenesis of the atopic march by allergen sensitization through the transcutaneous route. It is evident that external factors interact with the immune system, triggering a cascade of complex reactions that damage the epithelial barrier. Epigenetic and microbiome changes modulate the integrity of the epithelial barrier. Robust and simple measurements of the skin barrier dysfunction at the point‐of‐care are of significant value as a biomarker, as recently reported using electrical impedance spectroscopy to directly measure barrier defects. Understanding epithelial barrier dysfunction and its mechanism is key to developing novel strategies for the prevention and treatment of allergic diseases. The aim of this review is to summarize recent studies on the pathophysiological mechanisms triggered by environmental factors that contribute to the dysregulation of epithelial barrier function.

Atopic diseases of the parents predict the offspring's atopic sensitization and food allergy

BACKGROUND

In genetic studies and selected study populations, parental atopy has been associated with atopic diseases in offspring. Our aim was to identify the association between parental atopic diseases and the offspring's atopic sensitization and food allergies, and their effect modifications due to the offspring's sex.

METHODS

The study population (N = 5564) (born between 2001 and 2006) was identified from the population register and live in the province of South Karelia, Finland. Questionnaire-based information on parental atopic diseases was available for 3592 children. The results of skin prick tests, specific IgE tests, and open food challenges (OFC) were collected from patient records.

RESULTS

By 12 years of age, the cumulative incidence of sensitization to food (14% vs 7%, hazard ratio 2.13; 95% CI 1.68-2.69), animal (10% vs 6%, 1.86; 1.42-2.44), and pollen allergens (12% vs 6%, 2.43; 1.85-3.19), as well as food allergies (positive OFC, 5% vs 2%, 2.28; 1.57-3.33), was higher in the offspring of parents with atopic diseases. The cumulative incidence for pollen sensitization was twofold higher for the female offspring of parents with atopic diseases than those of parents without, while it was almost threefold higher among males. The association between parental pollen allergy and the offspring's pollen sensitization was modified by sex according to additive scale estimates (RERI 1.03; 95% CI 0.13-1.91).

CONCLUSION

Until adolescence, parental atopic diseases have a relatively strong association with the offspring's, particularly male offspring's, atopic sensitization, and food allergies. A pronounced association was found between parental pollen allergy and the male offspring's pollen sensitization.

Management of adult asthma and chronic rhinitis as one airway disease

Introduction: Chronic rhinitis is defined as nasal inflammation with the presence of minimum two symptoms such as nasal obstruction, rhinorrhea, sneezing and/or itching one hour daily for a minimum of 12 weeks/year. According their etiology, four groups of rhinitis are described: allergic, infectious, non-allergic non-infectious and mixed.Chronic rhinitis is frequently associated with asthma, shares similar mechanisms of the pathogenesis and has a negative impact of its outcomes sustaining the concept of unified airways disease.Areas covered: The present review summarizes the complex relationship between chronic rhinitis and asthma on the basis of recent epidemiological data, clinical characteristics, diagnosis and therapeutic management. All four groups are discussed with the impact of their specific treatment on asthma outcomes. Some medications are common for chronic rhinitis and asthma while others are more specific but able to treat the associated comorbidity.Expert opinion: The systematic assessment of chronic rhinitis in patients with asthma and its specific treatment improves both disease outcomes. Conversely, several therapies of asthma demonstrated beneficial effects on chronic rhinitis. Treating both diseases at the same time by only one medication is an interesting option to explore in the future in order to limit drugs administration, related costs and side effects.

Characterization of Asthma Trajectories from Infancy to Young Adulthood

BACKGROUND

Development of asthma is complicated by the multidimensional nature of the disease.

OBJECTIVE

To identify and characterize trajectories of asthma from infancy to young adulthood, and their associations with lung function and inflammatory and respiratory markers in adolescence and young adulthood.

METHODS

A latent class analysis was performed in a population-based cohort (N = 4089). Parental and self-reported symptoms of asthma were used to investigate asthma development. We characterized background factors, allergic comorbidity, and IgE sensitization and investigated associations with asthma markers.

RESULTS

A 4-class solution of asthma trajectories was identified: never/infrequent (n = 3291 [80.4%]), early-onset transient (n = 307 [7.5%]), adolescent-onset (n = 261 [6.4%]), and persistent asthma (n = 230 [5.6%]). Uncontrolled asthma was equally prevalent in the adolescent-onset and persistent asthma trajectory groups, at both age 16 (41.7% vs 42.4%; P = .90) and 24 years (53.7% vs 52.4%; P = .81). The persistent asthma trajectory group had a higher proportion of eosinophil counts greater than or equal to 0.3 (10⁹ cells/L) at age 24 years compared with the adolescent-onset trajectory group (31.0% vs 18.5%; P < .01).

CONCLUSIONS

The adolescent-onset and persistent asthma trajectory groups had equal burdens of asthma control in adolescence and young adulthood. However, the persistent asthma trajectory group showed more signs of type 2 inflammation than the adolescent-onset trajectory group. This unbiased approach highlights the need of identifying patients with adolescent asthma to optimize care, because they suffer the same lack of asthma control as those with persistent asthma.

Long and winding road: from infant wheeze to adult asthma

PURPOSE OF REVIEW

This review aims to recognize the multifactorial cause of asthma, from the influence of mother until adulthood, highlight the main characteristics of the disease at different ages and summarize the evidence of potential prevention strategies.

RECENT FINDINGS

To date, regarding the prenatal period, the presence of specific genes, maternal asthma, drugs, and tobacco exposure are the most relevant predisposing features for an asthmatic offspring. For newborns, preterm, bronchopulmonary dysplasia, and low birth weight has been associated with low lung function. Among young children, atopic dermatitis, lower respiratory tract infections, and increased levels of total Immunoglobulin E (IgE) and allergen-specific IgE are important determinants.Breastfeeding has been demonstrated being protective for the onset of asthma. Allergen immunotherapy has also been shown to have significant preventive effect decreasing asthma development. Inhaled corticosteroids use in early childhood prevents exacerbations but does not alter the natural history of asthma. Other interventions, such as the use of palivizumab, probiotics, vitamin D supplementation, and fish consumption presented controversial results.

SUMMARY

A good knowledge of risk factors for asthma development, from prenatal period to adulthood, may lead to efficacious preventive strategies. Further data of long-term follow-up in population-based studies according to different phenotypes are needed.

Self-Reported Allergic Rhinitis Prevalence and Related Factors in Civil Aviation Aircrew of China

INTRODUCTION: Allergic rhinitis (AR) is a global health problem with gradually increasing prevalence. No large-scale, systematic, and comprehensive study on AR among civil aviation aircrew of China has been reported. We aimed to demonstrate the prevalence of and risk factors for self-reported AR among Chinese civil aviation aircrew.METHODS: This study randomly surveyed 4059 civil aviation aircrew members from 12 cities in mainland China. A structured questionnaire was tailored, designed, and electronically delivered to all participants. Based on self-reported results, prevalence of and risk factors for AR were calculated/analyzed.RESULTS: The prevalence of self-reported AR was 23.38%. Among aircrew members, 10.37% presented with ear barotraumas, whereas 9.95% reported symptom aggravation during flight. Of aircrew members, 10.32% had symptoms related to flight duration, whereas 4.43% of symptoms related to flight altitude. Significant differences between rhinorrhea and sneezing, as well as between nasal itching and sneezing, were observed in the Total Nasal Symptoms Scores (TNSS). The Rhino-conjunctivitis Quality of Life Questionnaire (RQLQ) showed significant correlation between each section. TNSS was significantly related to RQLQ. Both TNSS and RQLQ significantly correlated with flight time.CONCLUSIONS: The prevalence of self-reported AR among civil aviation aircrew is higher than the general population in China. The severity of nasal symptoms and complications are significantly associated with quality of life and flying duties.Bai Y, Hu M, Ma F, Liu K, Xu H, Wu X, Wang H. Self-reported allergic rhinitis prevalence and related factors in civil aviation aircrew of China. Aerosp Med Hum Perform. 2021; 92(1):2531.

Risk factors associated with rhinitis, allergic conjunctivitis and eczema among schoolchildren in Uganda

Background

The prevalence of allergy-related diseases (ARDs), including rhinitis, allergic conjunctivitis and eczema, is on the increase globally. The causes of this increase are not well established.

Objectives

To investigate the risk factors associated with ARDs among schoolchildren in Uganda.

Methods

We conducted a secondary data analysis of a large asthma case–control study involving 1700 schoolchildren, 5–17 years, in urban Uganda. ARDs were defined according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Skin prick testing (SPT) was conducted using standard procedures and allergen-specific IgE (asIgE) using ImmunoCAP^®. We employed inverse probability weighted analysis to generate estimated prevalence data and weighted odds ratios.

Results

The lifetime estimated weighted prevalence of reported rhinitis, allergic conjunctivitis and eczema was 43.3%, 39.5% and 13.5%; weighted prevalence in 12 months was 10.1%, 9.1% and 2.3%, respectively. There was overlap of ARDs, with 66.3% of 1193 schoolchildren who reported having ever an ARDs (including asthma) reporting two or more. Risk factors associated with reported rhinitis in the last 12 months were city residence at birth [adjusted odds ratio (95% confidence interval) 2.66 (1.42–4.99) compared to rural]; father’s [2.62 (1.79–3.83)] and mother’s history of allergic disease [2.12 (1.48–3.02)]; frequent de-worming in the last 12 months [2.01 (1.30–3.11), ≥2 versus none]; current high frequency of ‘trucks passing on the street near home’ [2.59 (1.48–4.52), ‘almost all the time’ versus rarely] and positive SPT [1.54 (1.09–2.18)] but not asIgE [1.38 (0.60–3.15)]. The same pattern of risk factors was observed for allergic conjunctivitis and eczema.

Conclusion

We found extensive multi-morbidity of, and overlap in the risk factors for, rhinitis, conjunctivitis and eczema—similar to asthma risk factors—among schoolchildren in urban Uganda. This suggests a similar underlying cause for all ARDs, associated with exposure to urban lifestyles and environment in Uganda.

Atopic dermatitis

Atopic dermatitis (AD) is a common inflammatory skin disease, clinically characterized by recurrent eczematous lesions and intense itching, leading to excoriations and susceptibility to cutaneous infections. Although it is considered a pediatric disorder, mainly starting in infancy, it is also very common in adults. Etiology of AD is complex and multifactorial: interaction between genetic susceptibility and environment, but also cutaneous barrier impairment, change in microbiome composition and innate and adaptive immune dysregulation are the main factors involved in the pathogenesis of the disease. Originally, the disorder was considered mediated by an imbalance towards a T-helper 2 response and excessive IgE production to allergens, but now it is recognized as a lifelong disposition with variable clinical expressivity, where dysfunctions of the epidermal barrier, immune system and microbiome play a central role. AD leads to a substantial psycho-social burden on patients and their relatives and increases the risk of other allergic and non allergic disorders. The real economic impact of AD is difficult to measure due to the broad spectrum of disease severity and the multiple direct and indirect costs, but the overall medical expenses seem to be very high and similar to those of other diseases such as diabetes. Currently, a multiple therapeutic approach is aimed only at improving the skin state, reducing itching and keeping a stable condition. New safety and curative treatments may be developed only after enhancing our understanding on the pathogenesis of AD and the heterogeneity of its clinical manifestations. (www.actabiomedica.it)

The relationship of prenatal antibiotic exposure and infant antibiotic administration with childhood allergies: a systematic review

Background

Early antibiotic exposure may be contributing to the onset of childhood allergies. The main objective of this study was to conduct a systematic review on the relationship between early life antibiotic exposure and childhood asthma, eczema and hay fever.

Methods

Pubmed and Embase were searched for studies published between 01-01-2008 and 01-08-2018, examining the effects of (1) prenatal antibiotic exposure and (2) infant antibiotic administration (during the first 2 years of life) on childhood asthma, eczema and hay fever from 0 to 18 years of age. These publications were assessed using the Newcastle Ottawa Scale (NOS) and analysed narratively.

Results

(1) Prenatal antibiotics: Asthma (12 studies): The majority of studies (9/12) reported significant relationships (range OR 1.13 (1.02–1.24) to OR 3.19 (1.52–6.67)). Three studies reported inconsistent findings. Eczema (3 studies): An overall significant effect was reported in one study and in two other studies only when prenatal antibiotic exposure was prolonged. (2) Infant antibiotics: Asthma (27 studies): 17/27 studies reported overall significant findings (range HR 1.12 (1.08–1.16) to OR 3.21 (1.89–5.45)). Dose-response effects and stronger effects with broad-spectrum antibiotic were often reported. 10/27 studies reported inconsistent findings depending on certain conditions and types of analyses. Of 19 studies addressing reverse causation or confounding by indication at least somewhat, 11 reported overall significant effects. Eczema (15 studies): 6/15 studies reported overall significant effects; 9 studies had either insignificant or inconsistent findings. Hay fever (9 studies): 6/9 reported significant effects, and the other three insignificant or inconsistent findings. General: Multiple and broad-spectrum antibiotics were more strongly associated with allergies. The majority of studies scored a 6 or 7 out of 9 based on the NOS, indicating they generally had a medium risk of bias. Although most studies showed significant findings between early antibiotic exposure and asthma, the actual effects are still unclear as intrapartum antibiotic administration, familial factors and confounding by maternal and child infections were often not addressed.

Conclusions

This review points to a moderate amount of evidence for a relationship between early life antibiotics (especially prenatal) and childhood asthma, some evidence for a relationship with hay fever and less convincing evidence for a relationship with eczema. More studies are still needed addressing intra-partum antibiotics, familial factors, and possible confounding by maternal and childhood infections. Children exposed to multiple, broad-spectrum antibiotics early in life appear to have a greater risk of allergies, especially asthma; these effects should be investigated further.

Outside-in hypothesis revisited: The role of microbial, epithelial, and immune interactions

OBJECTIVE

Our understanding of the origin of allergic diseases has increased in recent years, highlighting the importance of microbial dysbiosis and epithelial barrier dysfunction in affected tissues. Exploring the microbial-epithelial-immune crosstalk underlying the mechanisms of allergic diseases will allow the development of novel prevention and treatment strategies for allergic diseases.

DATA SOURCES

This review summarizes the recent advances in microbial, epithelial, and immune interactions in atopic dermatitis, allergic rhinitis, chronic rhinosinusitis, and asthma.

STUDY SELECTIONS

We performed a literature search, identifying relevant recent primary articles and review articles.

RESULTS

Dynamic crosstalk between the environmental factors and microbial, epithelial, and immune cells in the development of atopic dermatitis, allergic rhinitis, chronic rhinosinusitis, and asthma underlies the pathogenesis of these diseases. There is substantial evidence in the literature suggesting that environmental factors directly affect barrier function of the epithelium. In addition, T-helper 2 (T_H2) cells, type 2 innate lymphoid cells, and their cytokine interleukin 13 (IL-13) damage skin and lung barriers. The effects of environmental factors may at least in part be mediated by epigenetic mechanisms. Histone deacetylase activation by type 2 immune response has a major effect on leaky barriers and blocking of histone deacetylase activity corrects the defective barrier in human air-liquid interface cultures and mouse models of allergic asthma with rhinitis. We also present and discuss a novel device to detect and monitor skin barrier dysfunction, which provides an opportunity to rapidly and robustly assess disease severity.

CONCLUSION

A complex interplay between environmental factors, epithelium, and the immune system is involved in the development of systemic allergic diseases.

EAACI Allergen Immunotherapy User's Guide

Allergen immunotherapy is a cornerstone in the treatment of allergic children. The clinical efficiency relies on a well-defined immunologic mechanism promoting regulatory T cells and downplaying the immune response induced by allergens. Clinical indications have been well documented for respiratory allergy in the presence of rhinitis and/or allergic asthma, to pollens and dust mites. Patients who have had an anaphylactic reaction to hymenoptera venom are also good candidates for allergen immunotherapy. Administration of allergen is currently mostly either by subcutaneous injections or by sublingual administration. Both methods have been extensively studied and have pros and cons. Specifically in children, the choice of the method of administration according to the patient's profile is important. Although allergen immunotherapy is widely used, there is a need for improvement. More particularly, biomarkers for prediction of the success of the treatments are needed. The strength and efficiency of the immune response may also be boosted by the use of better adjuvants. Finally, novel formulations might be more efficient and might improve the patient's adherence to the treatment. This user's guide reviews current knowledge and aims to provide clinical guidance to healthcare professionals taking care of children undergoing allergen immunotherapy.

Maternal oral contraceptive pill use and the risk of atopic diseases in the offspring: A systematic review and meta-analysis

Studies of maternal oral contraceptive pill (OCP) exposure and the offspring's risk of atopic diseases are of current interest due to concerns about widespread use of OCP before or during pregnancy.We evaluated whether maternal OCP exposure is associated with an increased risk of atopic diseases by reviewing the literature and performing a meta-analysis. The PubMed and Embase databases were searched to identify potential studies for inclusion. Three common atopic outcomes were included: asthma, eczema, and rhinitis.We found 693 titles, abstracts, and citations, and 6 studies were included in this analysis. A meta-analysis revealed that maternal OCP exposure was associated with higher odds of asthma (odds ratio [OR] 1.1; 95% confidence interval [CI] 1.02-1.19; P = .014), rhinitis (OR 1.34; 95% CI 1.07-1.68; P = .011) during childhood, whereas there was no association with eczema (OR 1.17; 95% CI 0.81-1.68; P = .383). This analysis was limited by the small number of studies included and the limited adjustments for the possible confounders in the studies.Current evidence suggests that maternal OCP exposure increases the risk for respiratory allergic diseases (asthma and rhinitis) in the offspring, but not for eczema. Given the few studies included, future larger, prospective studies that control for important confounders are needed to verify our findings.

Eczema phenotypes and risk of allergic and respiratory conditions in school age children

Background

Eczema phenotypes based on eczema onset and persistence might better identify groups prone to allergic and respiratory conditions than a binary definition of eczema. We examined the associations of childhood eczema phenotypes with allergic sensitization, allergy, asthma and lung function at school age.

Methods

This study among 4277 children was embedded in a multi-ethnic population-based prospective cohort study. Five eczema phenotypes (never, early transient, mid-transient, late transient, persistent) based on parental-reported physician-diagnosed eczema from age 6 months until 10 years were identified. At age 10 years, allergic sensitization was measured by skin prick tests, physician-diagnosed allergy and asthma by parent-reported questionnaires, and lung function by spirometry. Adjusted linear, logistic and multinomial regression models were applied.

Results

Compared with never eczema, all eczema phenotypes were associated with increased risks of asthma (odds ratios (OR) range (95% confidence interval): 2.68 (1.58, 4.57) to 11.53 (6.65, 20.01)), food and inhalant allergic sensitization (1.72 (1.25, 2.36) to 12.64 (7.20, 22.18)), and physician-diagnosed inhalant allergy (1.92 (1.34, 2.74) to 11.91 (7.52, 18.86)). Strongest effect estimates were observed of early and persistent eczema with the risk of physician-diagnosed food allergy (OR 6.95 (3.76, 12.84) and 35.05 (18.33, 70.00), respectively) and combined asthma and physician-diagnosed allergy (7.11 (4.33, 11.67) and 29.03 (15.27, 55.22), respectively). Eczema phenotypes were not associated with lung function measures.

Conclusion

Eczema phenotypes were differentially associated with risks of respiratory and allergic conditions in school-aged children. Children with early transient and persistent eczema might benefit from more intense follow-up for early identification and treatment of asthma and allergies.

Effect of omega-3 fatty acids supplementation during childhood in preventing allergic disease: a systematic review and Meta-Analysis

BACKGROUND

Early omega-3 fatty acids exposure can influence early immune development and potentially prevent allergic disease.

OBJECTIVES

To review the effects of omega-3 fatty acids during childhood on allergic disease outcomes.

METHODS

We conducted searches of the PubMed, EMBASE and Cochrane Central Register of Controlled Trials and international trial registers (ClinicalTrials.gov and ISRCTN Registry) to September 30, 2018. We included randomized controlled trials (RCTs) and prospective cohort studies regarding the effect of omega-3 fatty acids during childhood on allergic disease outcomes. A total of 8 publications from 2 prospective cohort studies and 6 reports representing 5 unique RCTs were included.

RESULTS

The results of meta-analysis showed that omega-3 fatty acids during childhood did not appear to significantly alter the risk of any atopy (≤3 years old: RR 0.70, 95% CI 0.47 to 1.04, p = 0.08; > 3 years old: RR 0.98, 95% CI 0.82 to 1.16, p = 0.77), wheeze (≤3 years old: RR 0.82, 95% CI 0.54 to 1.26, p = 0.375; > 3 years old: RR 1.03, 95% CI 0.53 to 2.00, p = 0.929) and eczema (≤3 years old: RR 0.86, 95% CI 0.68 to 1.08, p = 0.20; > 3 years old: RR 0.90, 95% CI 0.60 to 1.35, p = 0.60).

CONCLUSIONS

There is limited evidence to support omega-3 fatty acids during childhood could reduce the risk of allergic disease.

Recent developments and highlights in allergic rhinitis

Allergic rhinitis (AR) is a disease with high prevalence all over the world and therefore needs to be thoroughly investigated and treated accordingly. The mechanisms underlying the pathology and treatment of AR have been widely studied, but many aspects remain unclear and warrant further investigations. This review presents an overview of recently published papers highlighting the risk factors, mechanisms, and treatment of AR. Additionally, recent studies discussing the role of single nucleotide polymorphism, DNA methylation, regulatory B cells, group 2 innate lymphoid cells, immunotherapy, and biologics in AR are also covered.

Highlights and recent developments in airway diseases in EAACI journals (2018)

The European Academy of Allergy and Clinical Immunology (EAACI) supports three journals: Allergy, Pediatric Allergy and Immunology, and Clinical and Translational Allergy. EAACI's major goals include supporting the promotion of health, in which the prevention of allergy and asthma plays a critical role, and disseminating the knowledge of allergic disease to all stakeholders. In 2018, the remarkable progress in the identification of basic mechanisms of allergic and respiratory diseases as well as the translation of these findings into clinical practice were observed. Last year's highlights include publication of EAACI guidelines for allergen immunotherapy, many EAACI Position Papers covering important aspects for the specialty, better understanding of molecular and cellular mechanisms, identification of biomarkers for disease prediction and progress monitoring, novel prevention and intervention studies, elucidation of mechanisms of multimorbidities, introduction of new drugs to the clinics, recently completed phase three clinical studies, and publication of a large number of allergen immunotherapy studies and meta-analyses.

Childhood Respiratory Risk Factor Profiles and Middle-Age Lung Function: A Prospective Cohort Study from the First to Sixth Decade

RATIONALE

Childhood risk factors for long-term lung health often coexist and their specific patterns may affect subsequent lung function differently.

OBJECTIVES

To identify childhood risk factor profiles and their influence on lung function and chronic obstructive pulmonary disease (COPD) in middle age, and potential pathways.

METHODS

Profiles of 11 childhood respiratory risk factors, documented at age 7, were identified in 8,352 participants from the Tasmanian Longitudinal Health Study using latent class analysis. We investigated associations between risk profiles and post-bronchodilator lung function and COPD at age 53, mediation by childhood lung function and adult asthma, and interaction with personal smoking.

RESULTS

Six risk profiles were identified: 1) unexposed or least exposed (49%); 2) parental smoking (21.5%); 3) allergy (10%); 4) frequent asthma, bronchitis (8.7%); 5) infrequent asthma, bronchitis (8.3%); and 6) frequent asthma, bronchitis, allergy (2.6%). Profile 6 was most strongly associated with lower forced expiratory volume in 1 second (FEV₁) (-261; 95% confidence interval, -373 to -148 ml); lower FEV₁/forced vital capacity (FVC) (-3.4; -4.8 to -1.9%) and increased COPD risk (odds ratio, 4.9; 2.1 to 11.0) at age 53. The effect of profile 6 on COPD was largely mediated by adult active asthma (62.5%) and reduced childhood lung function (26.5%). Profiles 2 and 4 had smaller adverse effects than profile 6. Notably, the effects of profiles 2 and 6 were synergistically stronger for smokers.

CONCLUSIONS

Profiles of childhood respiratory risk factors predict middle-age lung function levels and COPD risk. Specifically, children with frequent asthma attacks and allergies, especially if they also become adult smokers, are the most vulnerable group. Targeting active asthma in adulthood (i.e., a dominant mediator) and smoking (i.e., an effect modifier) may block causal pathways and lessen the effect of such established early-life exposures.

Prioritizing research challenges and funding for allergy and asthma and the need for translational research-The European Strategic Forum on Allergic Diseases

The European Academy of Allergy and Clinical Immunology (EAACI) organized the first European Strategic Forum on Allergic Diseases and Asthma. The main aim was to bring together all relevant stakeholders and decision-makers in the field of allergy, asthma and clinical Immunology around an open debate on contemporary challenges and potential solutions for the next decade. The Strategic Forum was an upscaling of the EAACI White Paper aiming to integrate the Academy's output with the perspective offered by EAACI's partners. This collaboration is fundamental for adapting and integrating allergy and asthma care into the context of real-world problems. The Strategic Forum on Allergic Diseases brought together all partners who have the drive and the influence to make positive change: national and international societies, patients' organizations, regulatory bodies and industry representatives. An open debate with a special focus on drug development and biomedical engineering, big data and information technology and allergic diseases and asthma in the context of environmental health concluded that connecting science with the transformation of care and a joint agreement between all partners on priorities and needs are essential to ensure a better management of allergic diseases and asthma in the advent of precision medicine together with global access to innovative and affordable diagnostics and therapeutics.

Disease trajectories in childhood atopic dermatitis: an update and practitioner's guide

BACKGROUND

Atopic dermatitis (AD) is a heterogeneous disease with a multifactorial aetiology and complex pathophysiology. This heterogeneity translates into different trajectories of disease progression with respect to severity, persistence and risk of development of atopic comorbidities. Determining which possible disease trajectories or comorbidities any individual child might develop is challenging in clinical practice. Tools that help identify paediatric patients at higher risk of disease progression would greatly aid clinicians.

METHODS

We reviewed recent cohort studies to synthesize and simplify the epidemiological data to try to identify shared clinically relevant characteristics that may help physicians estimate the risk of disease progression in paediatric patients with AD.

RESULTS

Despite the variability in data collection and methods of analysis and their limitations, there are common patterns of early-childhood AD that may aid in the estimation of risk for disease progression. Factors associated with risk of AD progression include younger age of onset, family history of atopy, greater AD severity, filaggrin mutations, urban environment and polysensitization and/or allergic multimorbidity. Based on these factors, we provide a practitioner's guide for identifying, counselling and/or referring infants and children with AD at potentially higher risk of developing persistent AD and atopic comorbidities. We also present clinical scenarios to illustrate how these data relate to real-life situations.

CONCLUSIONS

Useful insights are provided for physicians and patients to inform them better about the risk of AD progression and to help guide care pathways for the paediatric population with AD. What's already known about this topic? The complex pathophysiology of atopic dermatitis (AD) translates into a heterogeneous clinical presentation and trajectories of disease progression. Although the consensus is that most paediatric patients with AD will eventually 'outgrow' the disease or follow the longitudinal trajectory known as the 'atopic march', a significant proportion will develop persistent AD and/or other atopic conditions. No known factors conclusively predict the risk of progression or development of comorbidities. What does this study add? Recent analyses of data from large cohorts of paediatric patients with AD have suggested the existence of potentially discrete clusters of patients who present with relatively common AD phenotypes. These studies have shed some light onto the factors associated with risk of progression, which we review in this article. A practitioner's guide with clinical scenarios is provided to help identify patients at high risk of progression to determine whether a patient should be monitored and/or would require specialist referral.

Changes in the prevalence of asthma and respiratory symptoms in western Sweden between 2008 and 2016

BACKGROUND

Asthma is a common chronic inflammatory disease of the airways, with a noticeable increase in prevalence during the second half of the 20th century. Recent studies assessing the prevalence trends among adults have been inconsistent. We investigated the changes in the prevalence of asthma, respiratory symptoms, and risk factors between 2008 and 2016 in western Sweden.

METHODS

The West Sweden Asthma Study (WSAS) is a population-based study which started in 2008 (WSAS I) and then repeated in 2016 (WSAS II) in western Sweden. Randomly selected individuals aged 16-75 years (N = 18 087 in 2008 and N = 24 534 in 2016) completed a questionnaire regarding obstructive lung diseases, respiratory symptoms, potential risk factors, and also questions from the GA² LEN survey.

RESULTS

The prevalence of reported ever asthma, physician-diagnosed asthma, use of asthma medication, and current asthma increased significantly from 9.6% to 11%, 8.3% to 10%, 8.6% to 9.8%, and 8.1% to 9.1%, respectively, between 2008 and 2016. There were also increases in the prevalence of respiratory symptoms during the same period. The greatest increase occurred in young adults aged 16-25 years. Female gender, allergic rhinitis, obesity, and family history of asthma remained the strongest risk factors for asthma in 2016 as it was in 2008.

CONCLUSION

There were moderate increases in asthma and respiratory symptoms in adults in western Sweden between 2008 and 2016, the greatest increase occurring in younger adults. The potential risk factors for asthma remained the same during the study period.

Influences of Maternal Factors Over Offspring Allergies and the Application for Food Allergy

The prevalence of food allergy has been steadily rising worldwide with the highest incidence noted among younger children, and increasingly recognized as a growing public concern. The first known ingestion of foods often causes allergic reaction, suggesting that sensitization of offspring with food allergens may occur during pregnancy and/or through breastfeeding. This creates a milieu that shapes the neonatal immune responses to these allergens. However, the effects of maternal allergen exposure and maternal sensitization with allergens on development of allergies in offspring remain controversial. This review discusses recent advances from human data in our understanding of how maternal factors, namely, food allergens, allergen-specific immunoglobulins, cytokines, genetics, and environmental factors transferred during pregnancy or breastfeeding influence offspring allergies and how such effects may be applicable to food allergy. Based on information obtained from mouse models of asthma and food allergy, the review also dissects the mechanisms by which maternal factors, including the impact of immune complexes, transforming growth factor-β, vitamin A, and regulatory T-cell responses, contribute to the induction of neonatal tolerance vs. development of allergic responses to maternally transferred allergens.

Filaggrin and atopic march

There is an increasing number of experimental, genetic and clinical evidence of atopic dermatitis expression as a pre-condition for later development of other atopic diseases such as asthma, food allergy and allergic rhinitis. Atopic dermatitis is a heterogeneous, recurrent childhood disease, also present in the adult age. It is increasingly attributed to systemic features and is characterized by immunological and skin barrier integrity and function dysregulation. To maintain the protective function of the skin barrier, in particular the maintenance of pH, hydration and antimicrobial functions, the filaggrin, among others, plays a significant role. Filaggrin is a multifunctional, histidine-rich, insoluble protein. The lack of filaggrin is associated with various cutaneous (e.g. ichthyosis vulgaris, allergic contact dermatitis) and non-cutaneous (e.g. diabetes, inflammatory conditions of the gastrointestinal tract) diseases and may be a result of genetic, immunological factors combined with environmental factors. In this review we summarised (emphasized) recent findings in understanding the role of filaggrin in atopic dermatitis and other diseases, participants in the atopic march.

PEBBLES study protocol: a randomised controlled trial to prevent atopic dermatitis, food allergy and sensitisation in infants with a family history of allergic disease using a skin barrier improvement strategy

INTRODUCTION

The skin is an important barrier against environmental allergens, but infants have relatively impaired skin barrier function. There is evidence that impaired skin barrier function increases the risk of allergic sensitisation, atopic dermatitis (AD) and food allergy. We hypothesise that regular prophylactic use of emollients, particularly those that are designed to improve skin barrier structure and function, will help prevent these conditions. With the aim of determining if application of a ceramide-dominant emollient two times per day reduces the risk of AD and food allergy, we have commenced a multicentre phase III, outcome assessor blinded, randomised controlled trial of this emollient applied from birth to 6 months.

METHODS AND ANALYSIS

Infants (n=760) with a family history of allergic disease will be recruited from maternity hospitals in Melbourne. The primary outcomes are as follows: the presence of AD, assessed using the UK Working Party criteria, and food allergy using food challenge, in the first 12 months of life as assessed by a blinded study outcome assessor. Secondary outcomes are as follows: food sensitisation (skin prick test), skin barrier function, AD severity, the presence of new onset AD after treatment cessation (between 6 and 12 months) and the presence of parent reported AD/eczema. Recruitment commenced in March 2018.

ETHICS AND DISSEMINATION

The PEBBLES Study is approved by the Human Research Ethics Committees of the Royal Children's Hospital (RCH) (#37090A) and the Mercy Hospital for Women (2018-008). Parents or guardians will provide written informed consent. Outcomes will be disseminated through peer-reviewed publications and presented at scientific conferences.

TRIAL REGISTRATION NUMBERS

ACTRN12617001380381 and NCT03667651.

Current therapeutic paradigm in pediatric atopic dermatitis: Practical guidance from a national expert panel

INTRODUCTION AND OBJECTIVES

Atopic dermatitis (AD) is the most common cutaneous inflammatory disease in both adults and children. Although emerging therapeutic approaches are being investigated for the management of pediatric AD, it still needs to be managed with conventional treatments. This consensus document is aimed at providing an update on general management and therapies of pediatric AD, defining practical recommendations for using both topical and systemic agents.

MATERIAL AND METHODS

A panel of experts consisting of dermatologists and pediatricians were convened in order to define statements, through a Delphi process, standardizing the management of AD in pediatric subjects in a real-world setting.

RESULTS

A set of practical recommendations obtaining an at least 75% agreement was presented.

CONCLUSIONS

This set of practical recommendations represents a simple and fast snapshot on the pediatric use of common anti-AD therapeutics.

Promoting and achieving excellence in the delivery of Integrated Allergy Care: the European Academy of Allergy & Clinical Immunology competencies for allied health professionals working in allergy

The multi-disciplinary team approach is an effective model for patient care. Allied health professionals (AHPs) are an important part of such teams, bringing specific knowledge and skills related to the target patient population. The AHPs most often involved in allergy care are nurses and dietitians. Nurses are often involved in the care of patients with all types of allergy and also with asthma, whilst allergy-specialist dietitians provide vital nutritional and dietary support for the diagnosis and management of food allergy. There are many other AHPs who have a role to play in allergy care, including physiotherapists, psychologists, pharmacists and speech therapists, and their involvement is likely to develop as allergy care becomes more rooted in the community. With the development of multi-professional teams comes the requirement for disease-specific knowledge and skill sets, with all allergy team members required to have baseline knowledge and competency of the condition being managed. Whilst some competencies for AHPs practising in other disease states have been published, none are available for allergic disease against which AHPs can be benchmarked. The European Academy of Allergy & Clinical Immunology (EAACI) recognised this need, and supported the establishment of a Task Force to develop allergy-focussed competencies for AHPs. The varied skills, expertise and professional background of the Task Force members enabled the creation of a set of allergy competencies relevant to all AHPs working in allergy. It is recognised that the training and allergy expertise of AHPs, and their role within the allergy setting, will vary considerably depending on the country. However, it is important for patient care, that all AHP involved in allergy services have access to training, of a sufficiently high enough level to be aspirational and enable the continued growth and development of a wide range of allergy services, given the increasing need. The EAACI competencies will provide an important benchmark for allergy knowledge and skills against which education and training can be designed and health care professionals can subsequently be measured. However, more importantly, the EAACI AHP allergy competencies will enable the development and reach of specialist allergy services, with allergy-specialist AHPs undertaking key roles, especially in the community care setting.

Epithelial barrier dysfunctions in atopic dermatitis: a skin-gut-lung model linking microbiome alteration and immune dysregulation

BACKGROUND

Atopic dermatitis is a systemic disorder characterized by abnormal barrier function across multiple organ sites. Causes of epidermal barrier breakdown are complex and driven by a combination of structural, genetic, environmental and immunological factors. In addition, alteration in microflora diversity can influence disease severity, duration, and response to treatment. Clinically, atopic dermatitis can progress from skin disease to food allergy, allergic rhinitis, and later asthma, a phenomenon commonly known as the atopic march. The mechanism by which atopic dermatitis progresses towards gastrointestinal or airway disease remains to be elucidated.

OBJECTIVES

This review addresses how epithelial dysfunction linking microbiome alteration and immune dysregulation can predispose to the development of the atopic march.

METHODS

A literature search was conducted using the PubMed database for relevant articles with the keywords 'atopic dermatitis', 'epithelial barrier', 'skin', 'gut', 'lung', 'microbiome' and 'immune dysregulation'.

RESULTS

Initial disruption in the skin epidermal barrier permits allergen sensitization and colonization by pathogens. This induces a T helper 2 inflammatory response and a thymic stromal lymphopoietin-mediated pathway that further promotes barrier breakdown at distant sites, including the intestinal and respiratory tract.

CONCLUSIONS

As there are no immediate cures for food allergy or asthma, early intervention aimed at protecting the skin barrier and effective control of local and systemic inflammation may improve long-term outcomes and reduce allergen sensitization in the airway and gut.

The future outlook on allergen immunotherapy in children: 2018 and beyond

Allergen immunotherapy (AIT) is the only currently available immune-modifying and aetiological treatment for patients suffering from IgE-mediated diseases. In childhood, it represents a suitable therapeutic option to intervene during the early phases of respiratory allergic diseases such as rhino-conjunctivitis and asthma, which is when their progression may be more easily influenced. A growing body of evidence shows that oral immunotherapy represents a promising treatment option in children with persistent IgE- mediated food allergy. The efficacy of AIT is under investigation also in patients with extrinsic atopic dermatitis, currently with controversial results. Furthermore, AIT might be a strategy to prevent the development of a new sensitization or of a (new) allergic disease. However, there are still some methodological criticisms, such as: a) the regimen of administration and the amount of the maintenance dose are both largely variable; b) the protocols of administration are not standardized; c) the description and classification of side effects is variable among studies and needs to be standardized; d) quality of life and evaluation of health economics are overall missing. All these aspects make difficult to compare each study with another. In addition, the content of major allergen(s) remains largely variable among manufacturers and the availability of AIT products differences among countries. The interest and the attention to AIT treatment are currently fervent and increasing. Well-designed studies are awaited in the near future in order to overcome the current gaps in the evidence and furtherly promote implementation strategies.