The atopic march: what's the evidence?

Atopic diseases-Diagnostics, mechanisms, and exposures

Epidemiological data suggest that atopic diseases begin in early life and that most cases present clinically during early childhood. The diseases are highly prevalent and increase as communities adopt western lifestyles. Disentangling the pathophysiological mechanisms leading to disease debut is necessary to identify beneficial/harmful exposures so that successful prevention and treatment can be generated. The objective of this review is to explore the definition of atopy and mechanisms of atopic diseases, and to investigate the importance of environmental factors in early life, prior to disease development. First, the distribution of sIgE levels in children is investigated, as this is one of the main criteria for the definition of atopy. Thereafter, it is explored how studies of parental atopic status, sensitization patterns, and early debut and severity of atopic dermatitis have substantiated the theory of an early-life window of opportunity for intervention that precedes the development of atopic diseases in childhood. Then, it is examined whether early-life exposures such as breastfeeding, dogs, cats, and house dust mites in the home perinatally constitute important influencers in this crucial time of life. Finally, it is discussed how these findings could be validated in randomized controlled trials, which might prepare the ground for improved diagnostics and prevention strategies to mitigate the current atopic pandemic.

Allergic Rhinitis

Allergic rhinitis (AR) affects more than 400 million people worldwide, making it 1 of the most prevalent chronic diseases. Childhood AR is increasing, and almost half of patients with AR develop symptoms before age 6 years. Although a diagnosis of AR is associated with higher socioeconomic status, underserved and urban populations have more indoor aeroallergen sensitizations and are likely underdiagnosed with AR, further exacerbating health-care disparities. AR negatively impacts quality of life, school performance, and overall health outcomes. Untreated AR in children increases the risk for poor asthma control, increased asthma severity, and exacerbations. Many patients believe that they have seasonal allergies only but in reality have both perennial and seasonal AR, which may change the approach to allergen avoidance measures and treatment recommendations. Pharmacotherapy of AR has expanded, with many intranasal corticosteroids, intranasal antihistamines, and second-generation oral antihistamines approved for pediatric use. Allergen immunotherapy, including both subcutaneous and sublingual forms, are approved for children and are disease modifying, potentially reducing further allergen sensitization and progression to asthma. Many of the currently available biological therapies indicated for pediatric asthma and/or atopic diseases reduce AR symptoms as well. Children with moderate to severe or refractory AR or those with comorbidities should be referred to allergists for diagnostic testing and expanded management options, including immunotherapy and potential biological treatment.

Whispers of change in preschool asthma phenotypes: Findings in the French ELFE cohort

RATIONALE

Early life asthma phenotyping remains an unmet need in pediatric asthma. In France, severe pediatric asthma phenotyping has been done extensively; however, phenotypes in the general population remain underexplored. Based on the course and severity of respiratory/allergic symptoms, we aimed to identify and characterize early life wheeze profiles and asthma phenotypes in the general population.

METHODS

ELFE is a general population based birth cohort; which recruited 18,329 newborns in 2011, from 320 maternity units nationwide. Data was collected using parental responses to modified versions of ISAAC questionnaire on eczema, rhinitis, food allergy, cough, wheezing, dyspnoea and sleep disturbance due to wheezing at 3 time points: post-natal (2 months), infancy (age 1) and pre-school (age 5). We built a supervised trajectory for wheeze profiles and an unsupervised approach was used for asthma phenotypes. Chi squared (χ2) test or fisher's exact test was used as appropriate (p < 0.05).

RESULTS

Wheeze profiles and asthma phenotypes were ascertained at age 5. Supervised wheeze trajectory of 9161 children resulted in 4 wheeze profiles: Persistent (0.8%), Transient (12.1%), Incident wheezers at age 5 (13.3%) and Non wheezers (73.9%). While 9517 children in unsupervised clusters displayed 4 distinct asthma phenotypes: Mildly symptomatic (70%), Post-natal bronchiolitis with persistent rhinitis (10.2%), Severe early asthma (16.9%) and Early persistent atopy with late onset severe wheeze (2.9%).

CONCLUSION

We successfully determined early life wheeze profiles and asthma phenotypes in the general population of France.

National Saudi Consensus Statement on the Management of Atopic Dermatitis (2021)

Atopic dermatitis (AD) is a chronic inflammatory skin disease with an increasing prevalence regionally and globally. It is characterized by intense itching and recurrent eczematous lesions. With the increase in the availability of treatment options for healthcare practitioner and patients, new challenges arise for treatment selection and approach. The current consensus statement has been developed to provide up-to-date evidence and evidence-based recommendations to guide dermatologists and healthcare professionals managing patients with AD in Saudi Arabia. By an initiative from the Ministry of Health (MOH), a multidisciplinary work group of 11 experts was convened to review and discuss aspects of AD management. Four consensus meetings were held on January 14, February 4, February 25, and March 18 of 2021. All consensus content was voted on by the work group, including diagnostic criteria, AD severity assessment, comorbidities, and therapeutic options for AD. Special consideration for the pediatric population, as well as women during pregnancy and lactation, was also discussed. The present consensus document will be updated as needed to incorporate new data or therapeutic agents.

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.

Prevalence and Risk Factors Associated with the Occurrence of Autoimmune Diseases in Patients with Alopecia Areata

BACKGROUND

Increased rates of autoimmune diseases (ADs) have been reported in association with alopecia areata (AA); however, the risk factors for coexisting ADs in AA patients have been poorly investigated.

OBJECTIVE

To evaluate the prevalence and factors associated with AD comorbidities in patients with AA.

METHODS

This case-control study included patients diagnosed with AA between January 2000 and March 2020. Individuals with AA, both with and without concomitant ADs, were statistically compared. Variables significantly associated with coexisting ADs were identified using univariate and multivariate logistic regression analyses. Multinomial logistic regression analysis was performed to identify the specific risk factors for each concomitant AD.

RESULTS

Among the 615 patients with AA, comorbid ADs were found in 76 (12.4%). Autoimmune thyroid disease (AITD) exhibited the highest frequency (n = 42, 6.8%), followed by vitiligo (n = 15, 2.4%), and systemic lupus erythematosus (SLE) (n = 12, 2.0%). Logistic regression analyses revealed that female sex (odds ratio [OR] = 2.45, 95% confidence interval [CI] = 1.24-4.82; P = 0.011), nail abnormalities (OR = 2.49, 95% CI = 1.14-5.46; P = 0.023), and atopic diseases (OR = 1.98, 95% CI = 1.09-2.43; P < 0.001) were significantly associated with coexisting ADs. Regarding each concomitant AD, nail abnormalities were an associated factor for AITD (OR = 4.65, 95% CI = 1.96-7.24; P = 0.01), whereas coexisting atopic diseases were demonstrated as a predictor of vitiligo (OR = 2.48, 95% CI = 1.43-4.58; P = 0.02). Female sex (OR = 1.61, 95% CI = 1.18-4.27; P = 0.04) and family history of AD (OR = 1.85, 95% CI = 1.26-4.19; P = 0.03) were predictors of SLE.

CONCLUSION

This study suggests that female AA patients with nail abnormalities and atopic diseases have increased rates of AD comorbidities. A thorough review of systems for associated factors can help physicians screen for concomitant ADs.

Histopathological Characteristics of Limbal Stem Cell Deficiency Secondary to Chronic Vernal Keratoconjunctivitis

PURPOSE

To describe the histopathological characteristics of limbal stem cell deficiency (LSCD) due to chronic vernal keratoconjunctivitis (VKC).

METHODS

This retrospective study included 14 eyes of 13 patients who underwent simple limbal epithelial transplantation for total LSCD from 2017 to 2018. The histological characteristics of the excised fibrovascular pannus were compared between 2 groups of 7 eyes, each with LSCD due to VKC and chemical burns (CB). Histological characteristics and type of inflammation were studied using special stains and immunohistochemistry. Fisher exact test was used to detect the statistical significance of the histological differences between both groups.

RESULTS

Epithelial hypertrophy, epithelial downgrowth, and eosinophilic infiltration were noted in all eyes in the VKC group (7/7, 100%). Epithelial hypertrophy was noted in 3 of the 7 (42.8%) eyes in the CB group, whereas epithelial downgrowth and eosinophilic infiltrates were absent. The average chronic inflammatory score of the pannus (5.28) was higher in VKC than in CB (3.85; P = 0.1080). The presence of goblet cells was higher in the CB group (5/7, 1.4%) than in the VKC group (3/4, 2.8%), although not statistically significant. Other histological differences between the groups were not statistically significant.

CONCLUSIONS

The histopathological features of LSCD in VKC reveal some distinctive characteristics. These include the presence of epithelial downgrowth, eosinophilic infiltration, and epithelial solid and cystic implants. Although this information may be used to establish the diagnostic criteria for VKC as the cause of LSCD, further studies are needed to elucidate the reasons behind these unique findings.

Atopy risk among school-aged children in relation to early exposures to a farm environment: A systematic review

BACKGROUND AND OBJECTIVES

Childhood atopy is a complex condition with both a genetic and an environmental component. This systematic review will explore the current understanding of the importance of early life exposures to a farm in the development of atopy measured by objective markers of skin prick testing, and specific IgE measurements in school age children.

METHODS

A systematic review was performed.

RESULTS

Among 7285 references identified, 14 studies met the inclusion criteria (13 cross-sectional studies and 1 case-control study). The results were fairly consistent in that early farm-related exposures can protect children from becoming atopic at school age. In general, there was heterogeneity in the assessment of outcomes and exposures.

CONCLUSIONS

Early-life farm exposures are associated with a protective effect on childhood atopy as assessed by objective markers. Future work should focus on understanding specific farm exposures that may important in these associations between atopy and farm exposures in children.

Burden and socioeconomics of asthma, allergic rhinitis, atopic dermatitis and food allergy

INTRODUCTION

Asthma, allergic rhinitis, atopic dermatitis, and food allergy affect approximately 20% of the global population. Few studies describe the burden of the totality of these diseases and only a handful studies provide a comprehensive overview of the socioeconomic impact of these diseases.

AREAS COVERED

For this narrative review, we searched Pubmed using selected keywords and inspected relevant references using a snowballing process. We provide an overview of the socioeconomic burden of allergic diseases (in particular, asthma, allergic rhinitis, atopic dermatitis, and food allergy). The focus of this review is on their epidemiology (incidence, prevalence), burden (disability-adjusted life years, quality of life), and direct and indirect costs (absenteeism and presenteeism). We have put special emphasis on differences between countries.

EXPERT COMMENTARY

Both the prevalence and the burden of allergic diseases are considerable with prevalence varying between 1% and 20%. We identified a plethora of studies on asthma, but studies were generally difficult to compare due to the heterogeneity in measures used. There were only few studies on the burden of food allergy; therefore, more studies on this allergy are required. For future studies, we recommend standardizing epidemiologic, socioeconomic impact, and quality of life measures of allergic diseases.

PFAS (per- and polyfluoroalkyl substances) and asthma in young children: NHANES 2013-2014

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent chemicals used as industrial surfactants, fire-fighting foams, and textile treatments. Early childhood exposure to perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS) may affect the immune system to increase the risk of allergic and respiratory diseases. However, there are substantial gaps in our knowledge about the relationship between PFAS and immune-mediated outcomes such as asthma in children. Thus, we examined the cross-sectional associations of serum PFOA, PFOS, PFNA, and PFHxS concentrations with childhood asthma. We used data from children aged 3-11 years who participated in the National Health and Nutrition Examination Survey (2013-2014). Serum PFAS concentrations were measured in serum using analytical chemistry methods. Asthma was assessed by parent-reported, doctor-diagnosed, asthma using a standardized questionnaire. Controlling for covariates, we estimated odds ratios for asthma per standard deviation increase in ln-transformed serum PFAS concentrations (n = 607). We also examined effect measure modification by child age, sex, and race/ethnicity. PFOA (1.1; 95% CI: 0.8, 1.4), PFOS (1.2; 95% CI: 0.8, 1.7), PFNA (1.1; 95% CI: 0.8, 1.6), and PFHxS (1.1; 95% CI: 0.9, 1.6) were weakly associated with an increased odds of asthma. Age modified associations between serum PFOS, but not other serum PFAS concentrations, and odds of asthma (age x PFOS interaction term p-value = 0.03). Sex and race/ethnicity did not modify these associations. We observed some evidence that serum PFAS concentrations are weakly associated with increased asthma prevalence in US children.

Atopic Disease and Anemia in Korean Patients: Cross-Sectional Study with Propensity Score Analysis

Atopic disease is associated with chronic inflammation, and anemia has been reported in patients with inflammatory disorders such as rheumatoid arthritis, chronic obstructive pulmonary disease, and irritable bowel disease. The objective of this study was to determine whether atopic disease is associated with an increased risk of anemia. A cross-sectional study with propensity score weighting was conducted using a health insurance review agency claims dataset comprised of randomized patients who used the Korean national health system at least once in 2016. The association between atopic disease (asthma, atopic dermatitis, allergic rhinitis) and anemia (iron deficiency anemia (IDA) and/or anemia of inflammation (AI)) was examined. A total of 1,468,033 patients were included in this study. The IDA/AI prevalence was 3.1% (45,681 patients). After propensity score weighting, there were 46,958 and 45,681 patients in the non-anemic and anemic groups, respectively. The prevalence of IDA/AI in patients with atopic dermatitis, allergic rhinitis, or asthma had an odds ratio (OR) of 1.40 (95% confidence interval (CI), 1.33–1.48; p < 0.001), 1.17 (95% CI, 1.14–1.21; p < 0.001), and 1.32 (95% CI, 1.28–1.36; p < 0.001), respectively. In addition, the prevalence of IDA increased with higher numbers of atopic diseases. In conclusion, the prevalence of IDA/AI was higher in patients with atopic disease, even after adjusting for demographic characteristics and other risk factors. Further study is needed to distinguish between IDA and AI and to enhance understanding of the etiology of anemia in patients with inflammatory conditions.

The Impact of Early-Life Exposure to Antimicrobials on Asthma and Eczema Risk in Children

PURPOSE OF REVIEW

We examined recent research on associations of prenatal and early-childhood exposure to the antimicrobial compounds, triclosan, and parabens, with the risk of asthma and eczema in children. We will discuss potential biological mechanisms of this association and highlight strengths and limitations of the study design and exposure assessment of current findings.

RECENT FINDINGS

Results of available toxicological and epidemiologic studies indicate a potential link of triclosan and paraben exposures with asthma and eczema in children, as well as changes in microbiome diversity and immune dysfunction, which could possibly mediate an association with the health outcomes. A small number of studies suggest that triclosan and paraben exposures could be related to the risk of asthma and eczema in children. Although current findings are far from conclusive, there is emerging evidence that changes in microbiome diversity and immune function from antimicrobial exposure may mediate these relations.

Allergies, asthma, and psychopathology in a nationally-representative US sample

BACKGROUND

Symptoms of depressed mood and anxiety have been associated with immune dysregulation and atopic disorders, however it is unclear whether this relationship spans other forms of psychopathology. The objective of this study was to use a large, population-based sample to examine the association between several common psychiatric conditions and two atopic disorders: seasonal allergies and asthma. This study also examined whether comorbidity between psychiatric disorders confounded the relationship between atopy and each psychiatric disorder.

METHODS

Data come from the Comprehensive Psychiatric Epidemiology Surveys, a nationally-representative sample of US adults (N = 10,309). Lifetime history of major depressive disorder (MDD), generalized anxiety disorder (GAD), panic disorder (PD), and post-traumatic stress disorder (PTSD) was assessed using the Composite International Diagnostic Inventory. History of seasonal allergies and asthma were assessed by self-report. Weighted logistic regression was used to evaluate the association between allergies and asthma and psychopathology. Psychiatric comorbidities were also examined as potential confounders.

RESULTS

Approximately 36.6% had a history of allergies and 11.5% a history of asthma. Seasonal allergies were positively associated with odds of MDD (Odds ratio (OR): 1.24, 95% Confidence Interval (CI): 1.06-1.46), GAD (OR: 1.54 (1.28-1.84)), PD (OR: 1.54 (1.24-1.91)), and PTSD (OR: 1.32 (1.09-1.59)). Asthma was not significantly associated with any psychiatric disorder. All significant associations persisted after adjustment for psychiatric comorbidities.

LIMITATIONS

Limitations include self-reporting of atopic disorder status and of all disorder ages of onset.

CONCLUSIONS

This study confirms the association between MDD and PD and seasonal allergies, and extends this relationship to GAD and PTSD.

Diverse age-incidence patterns of atopic sensitization in an unselected Finnish population up to 12 years

BACKGROUND

The temporal sequence in which allergic sensitization to different allergens emerges is not well characterized at the level of general population.

OBJECTIVE

We describe the incidence patterns of atopic sensitization to different allergens from birth up to 12 years of age in an unselected Finnish population.

METHODS

The study population comprised all children born between 2001 and 2006 identified from the nationwide population register as residents of the province of South Karelia, Finland (n = 5564). The results of allergy tests (22,380 results from skin prick tests, immunoglobulin E [IgE] antibodies, and open food challenges [OFCs], performed in 1827 children) were collected from patient records of all the health care units in the area.

RESULTS

The incidence rates of positive results for food and animal allergens as well as positive OFCs for cow's milk showed prominent peaks at 5 months of age. Positive results for pollen allergens started to emerge after 1.5 years of age. The 12-year cumulative incidence of sensitization to food, animal, pollen, and any allergens was 12%, 8%, 10%, and 18%, respectively. The cumulative incidence of sensitization to house dust mites was 1% and to molds or latex less than 1%. Firstborn boys had the highest, and those who were not firstborn girls and children born in rural municipalities had the lowest early incidence of sensitization to inhalation allergens.

CONCLUSION

In the unselected population, the atopic sensitization against food and animal allergens began before 6 months of age and was followed by sensitization to pollen allergens before 2 years of age. Primary prevention of sensitization to food and inhalation allergens should therefore occur in early infancy.

The pertussis hypothesis: Bordetella pertussis colonization in the etiology of asthma and diseases of allergic sensitization

Decades of peer reviewed evidence demonstrate that: 1)Bordetellapertussisand pertussis toxin are potent adjuvants, inducing asthma and allergic sensitization in animal models of human disease, 2)Bordetella pertussisoften colonizes the human nasopharynx, and is well documented in highly pertussis-vaccinated populations and 3) in children, a history of whooping cough increases the risk of asthma and allergic sensitization disease. We build on these observations with six case studies and offer a pertussis-based explanation for the rapid rise in allergic disease in former East Germany following the fall of the Berlin Wall; the current asthma, peanut allergy, and anaphylaxis epidemics in the United States; the correlation between the risk of asthma and gross national income per capita by country; the lower risk of asthma and allergy in children raised on farms; and the reduced risk of atopy with increased family size and later sibling birth order. To organize the evidence for the pertussis hypothesis, we apply the Bradford Hill criteria to the association between Bordetella pertussisand asthma and allergicsensitization disease. We propose that, contrary to conventional wisdom that nasopharyngealBordetella pertussiscolonizing infections are harmless, subclinicalBordetella pertussiscolonization is an important cause of asthma and diseases of allergic sensitization.

Inflammatory Markers and Genetic Polymorphisms in Workers Exposed to Flour Dust

OBJECTIVE

The aim of this study is to evaluate inflammatory markers and pro-inflammatory CD14 and Toll-like Receptor 4 (TLR4) polymorphisms in workers exposed to flour dust.

METHODS

Polymorphisms in TLR4 and CD14 were identified in our study population of 167 workers that included 63 healthy subjects (HS), 45 atopic subjects (A), and 59 subjects diagnosed clinically with occupational asthma/rhinitis (OAR). Endpoint measures in this study included fractional exhaled nitric oxide and serum concentrations of interleukin IL-6, IL-8, and tumor necrosis factor-alpha (TNF-α).

RESULTS

We identified a polymorphism in CD14 (rs2569190) that may be differentially expressed (P = 0.06). IL-6 concentrations in the serum were significantly higher in the A and OAR groups (P < 0.01) than in subjects in the HS group, while IL-8 concentrations were significantly elevated only in the OAR group (P < 0.01). Interestingly, TNF-α concentrations in the OAR group were significantly reduced when compared with subjects in the HS group (P < 0.01).

CONCLUSION

Cytokines are likely a defensive response in atopic and healthy workers. A protective genotype is hypothesized for occupational asthma.

Risk factors for asthma occurrence in children with early-onset atopic dermatitis: An 8-year follow-up study

BACKGROUND

Children with early-onset atopic dermatitis (AD) are at substantial risk of developing asthma later in life, and identifying the critical window of detrimental exposure is advantageous for implementing preventive actions. The aim of this study was to evaluate the role of exposure to environmental modifiers during pregnancy and early childhood in asthma occurrence in an infantile AD cohort.

METHODS

Eligible study participants were selected from the Taiwan Birth Cohort Study, which enrolled 24 200 newborns in 2005. We enrolled those cases who had been diagnosed as having AD before 3 years of age and followed them up till age 8. We excluded those ever diagnosed with asthma before AD onset. The dependent variable was defined in terms of whether the participant was diagnosed as having asthma before 8 years of age. We applied logistic regression models to evaluate the risks of exposure to different determinants in asthma occurrence.

RESULTS

A total of 1549 children with AD had completed the 8-year follow-up, and 334 (21.6%) of them had asthma. The results revealed that male sex, lower birth order, maternal asthma history, maternal obesity before pregnancy, and environmental tobacco smoke exposure before 3 years of age were significant risk factors for further development of asthma. Furthermore, food allergy during early life, lower respiratory tract infection, and longer durations of symptomatic AD influenced asthma development later in life.

CONCLUSIONS

The findings confirmed the critical determinants for asthma occurrence in infantile AD, which may enable a more personalized approach to the prevention of asthma.

Natural evolution in patients with nonsteroidal anti-inflammatory drug-induced urticaria/angioedema

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most frequent triggers of drug hypersensitivity with NSAIDs-induced urticaria/angioedema (NIUA) the most common phenotype. Loss of hypersensitivity has been reported for IgE-mediated reactions; however, it has not been assessed in nonimmunological reactions such as NIUA. We evaluated NSAID-hypersensitivity over time in NIUA patients.

METHODS

Patients confirmed as NIUA by positive drug provocation test (DPT) with acetylsalicylic acid (ASA) during 2005-2012 (V1) were included (n=38). Subjects were prospectively re-evaluated by DPT with ASA/other NSAIDs at two time points between 2013 and 2015 (V2 and V3). Atopy was assessed by skin prick test (SPT) using inhalant and food allergens.

RESULTS

Patients were evaluated at V1 and re-evaluated after 60 months (V2; IR:48-81) and a further 18 months (V3; IR:14-24). At V2, the majority (24; 63.15%) tolerated ASA and other NSAIDs (Group A) while 14 (36.84%) still reacted (Group B). At V3, all Group A patients remained tolerant; all Group B patients remained hypersensitive. The number of previous episodes reported at V1 and the percentage of reactions induced by ASA/ibuprofen were significantly lower in Group A (P=.005 and P=.006, respectively). Group A patients developed tolerance 72 months (IR:45-87) after their last evaluated reaction (V1); this interval was shorter in nonatopics (P=.003), patients who experienced reactions over 1 hour after NSAIDs administration (P=.001), and those who experienced isolated urticaria after NSAID intake (P=.024).

CONCLUSIONS

NIUA patients may develop tolerance to NSAIDs over time, a process that seems to be influenced by atopy and type of clinical reaction.

Maternal sensitivity and social support protect against childhood atopic dermatitis

BACKGROUND

Many studies have identified associations between qualities of maternal-child relationships and childhood asthma, but few have examined associations with childhood atopic dermatitis (AD), a common precursor to asthma. Moreover, maternal psychological distress, including prenatal and postnatal depression, anxiety and stress, may increase risk, while social support from partners may reduce risk for childhood AD. We sought to uncover the association between maternal-infant relationship qualities (maternal sensitivity towards infant behavioral signals, controlling behavior, and unresponsiveness) and child AD after accounting for risk (i.e., prenatal and postnatal maternal depression, anxiety and stress) and protective (i.e., social support) factors.

METHODS

We conducted a secondary analysis of data collected on a subsample of 242 women and their infants enrolled during pregnancy in the ongoing Alberta Pregnancy Outcomes and Nutrition cohort study. Inclusion criteria required mothers to be >16 years of age, English speaking and <22 weeks gestational age at enrollment. Data on depression, anxiety and stress in the prenatal and postnatal periods and physician diagnosis of childhood AD at 18 months were gathered via maternal report. Maternal sensitivity, unresponsiveness and controlling behaviours were assessed via videotaped observations using the Child-Adult Relationship Experimental (CARE)-Index at 6 months of infant age.

RESULTS

Higher maternal sensitivity, or the inability of the mother to appropriately understand and respond to infant needs based on behavioral signals, predicted reduced odds of AD independent of and in combination with low prenatal and postnatal anxiety and high paternal support. After adjustment, higher maternal controlling behaviours and unresponsiveness also predicted greater odds of AD.

CONCLUSIONS

Low maternal sensitivity is a risk factor for childhood AD, independently and in combination with perinatal anxiety and low social support. Thus, interventions that improve maternal-infant relationship quality, especially sensitivity, reduce anxiety and improve social support from partners could reduce odds of childhood AD.

Is there a march from early food sensitization to later childhood allergic airway disease? Results from two prospective birth cohort studies

BACKGROUND

The march from early aeroallergen sensitization to subsequent respiratory allergy is well established, but it is unclear whether early life food sensitization precedes and further increases risk of allergic airway disease.

OBJECTIVE

To assess the association between food sensitization in the first 2 years of life and subsequent asthma and allergic rhinitis by age 10-12 years.

METHODS

We used data from two independent cohorts: the high-risk Melbourne Atopic Cohort Study (MACS) (n = 620) and the population-based LISAplus (n = 3094). Food sensitization was assessed at 6, 12, and 24 months in MACS and 24 months in LISAplus. Multiple logistic regressions were used to estimate associations between sensitization to food only, aeroallergen only, or both and allergic airway disease.

RESULTS

When compared to non-sensitized children, sensitization to food only at 12 months in MACS and 24 months in LISAplus was associated with increased risk of current asthma (aOR = 2.2; 95% CI 1.1, 4.6 in MACS and aOR = 4.9; 2.4, 10.1 in LISAplus). Similar results were seen for allergic rhinitis. Additionally, cosensitization to food and aeroallergen in both cohorts at any tested point was a stronger predictor of asthma (at 24 months, aOR = 8.3; 3.7, 18.8 in MACS and aOR = 14.4; 5.0, 41.6 in LISAplus) and allergic rhinitis (at 24 months, aOR = 3.9; 1.9, 8.1 in MACS and aOR = 7.6; 3.0, 19.6 in LISAplus).

CONCLUSIONS

In both cohorts, food sensitization (with or without aeroallergen sensitization) in the first two years of life increased the risk of subsequent asthma and allergic rhinitis. These findings support the role of early life food sensitization in the atopic march and suggest trials to prevent early onset have the potential to reduce the development of allergic airways disease.

The Role of Sensitization to Allergen in Asthma Prediction and Prevention

The burden of asthma in childhood is considerable worldwide, although some populations are much more affected than others. Many attempts have been made by different investigators to identify the factors that could predict asthma development or persistence in childhood. In this review, the relation between atopic sensitization as an indicator of allergy and asthma in childhood will be discussed. Cross sectional studies, carried out in different countries, failed to show any firm correlation between asthma and atopic sensitization. Birth cohort mainly of infants at high risk for asthma and case-control studies showed that atopic sensitization was a risk factor for current asthma in children older than 6 years. In general, clear relations are observed mostly in affluent Western countries, whereas in less affluent countries, the picture is more heterogeneous. For the prediction of asthma development or persistence in school age children, other prerequisites should also be fulfilled such as family history of asthma and wheezing episodes at preschool age. Despite the conductance of different studies regarding the potential role of allergen avoidance for the primary prevention of childhood asthma, it does not seem that this approach is of benefit for primary prevention purposes. However, the identification of children at risk for asthma is of benefit as these subjects could be provided with the best management practices and with the appropriate secondary prevention measures.

Mould-sensitized adults have lower Th2 cytokines and a higher prevalence of asthma than those sensitized to other aeroallergens

BACKGROUND

Evidence suggests that specific allergen sensitizations are associated with different allergic diseases which may reflect different underlying immune profiles. We aimed to examine the cytokine profiles of individuals sensitized to eight common aeroallergens.

METHODS

We used data from the Tasmanian Longitudinal Health Study a population-based cohort study of 45-year-olds. Serum cytokines (IL-4, IL-5, IL-6, IL-8, IL-10, TNF-α) were measured in 1157 subjects using the LINCOplex assays. Participants underwent skin prick testing for house dust mite, cat, grasses and moulds. Multivariable linear regression was used to compare serum cytokine levels between sensitized and nonatopic subjects.

RESULTS

The prevalence of allergic sensitization to any aeroallergen was 51% (95% CI 47-54). Being sensitized to any aeroallergen was strongly associated with current asthma (OR = 3.7, 95% CI 2.6-5.3), and being sensitized to any moulds was associated with a very high risk of current asthma (OR = 6.40, 95% CI 4.06-10.1). The geometric mean (GM) levels of Th2 cytokines (IL-4, IL-5 and IL-6) for adults sensitized to Cladosporium were significantly lower than the levels for nonatopic individuals (IL-4 ratio of GMs = 0.25, 95% CI 0.10-0.62, P = 0.003; IL-5 GM = 0.55, 95% CI 0.30-0.99, P = 0.05; and IL-6 GM = 0.50, 95% CI 0.24-1.07, P = 0.07). Individuals sensitized to other aeroallergens all showed elevated Th2 cytokine levels.

CONCLUSION

Our study is the first large population-based study to demonstrate reduced Th2 cytokines levels in people sensitized to mould. Underlying biological mechanisms driving allergic inflammatory responses in adults sensitized to moulds may differ from those sensitized to other aeroallergens. These findings suggest that it may be necessary to tailor treatments in individuals sensitized to moulds compared with other aeroallergens in order to optimize outcomes.

The allergic march comprises the coexistence of related patterns of allergic disease not just the progressive development of one disease

Aim

This study explored the development and comorbidity of allergic diseases by analysing the relationship between allergic manifestations in infancy and at the age of 8.

Methods

We included 5654 children born in Sweden in 2003 in a longitudinal study. Parents answered postal questionnaires when the children were six months and one, four‐and‐a‐half and eight years of age.

Results

The response rate at eight years was 4051 (71.6%), and we analysed 3382 children with complete data. The number of manifestations in infancy increased the risk of allergic disease at eight years of age: 72% of children with one early manifestation were symptom free at 8, compared to 45% with two or more manifestations. Similar manifestations occurred in infancy and at the age of 8, for example recurrent wheeze increased the risk of doctor‐diagnosed asthma by an adjusted odds ratio of 6.5. Eczema and food allergy independently increased the risk of all four allergic manifestations at eight years.

Conclusion

Allergic disease at the age of 8 was related to the number of allergic manifestations in infancy. Manifestations were similar at both ages, suggesting an allergic march with the coexistence of disease patterns rather than the progressive development of one disease.

Viruses and bacteria in Th2-biased allergic airway disease

Allergic airway diseases are typically characterized by a type 2-biased inflammation. Multiple distinct viruses and bacteria have been detected in the airways. Recently, it has been confirmed that the microbiome of allergic individuals differs from that of healthy subjects, showing a close relationship with the type 2 response in allergic airway disease. In this review, we summarize the recent findings on the prevalence of viruses and bacteria in type 2-biased airway diseases and on the mechanisms employed by viruses and bacteria in propagating type 2 responses. The understanding of the microbial composition and postinfectious immune programming is critical for the reconstruction of the normal microflora and immune status in allergic airway diseases.

Variable risk of atopic disease due to indoor fungal exposure in NHANES 2005-2006

BACKGROUND

Exposure to damp indoor environments is associated with increased risk of eczema, allergy and asthma. The role of dampness-related exposures and risk of allergic diseases are yet to be fully explored in the US population.

OBJECTIVE

We assess whether exposure to fungi, house dust mites and endotoxin increases the risk of eczema, allergy and asthma in children and adults participating in NHANES 2005-2006.

METHODS

A total of 8412 participants (2849 were children aged between 6 and 17 years) were recruited in the 2005-2006 survey. We used multiple logistic regression to investigate whether mildew/musty odour and increased concentrations of Alternaria alternata allergen, Aspergillus fumigatus antigens, house dust mite and endotoxin antigens increase the risk of eczema, allergy and asthma. We stratified models by total IgE < 170 and ≥ 170 KU/L to assess allergic and non-allergic asthma outcomes. Exposure to multiple biological agents and risk of reporting eczema, allergy and asthma were also investigated.

RESULTS

Reporting of a mildew/musty odour was associated with increased risk of childhood asthma (OR 1.60; 95% CI 1.17-2.19), and adult eczema, allergy and asthma (OR 1.92; 95% CI 1.39-2.63, OR 1.59 95% CI 1.26-2.02 and OR 1.61 95% CI 1.00-2.57, respectively). Risk of asthma was associated with total IgE ≥ 170 KU/L in children (OR 1.81; 95% CI 1.01-3.25) and total IgE < 170 KU/L in adults (OR 1.91; 95% CI 1.07-3.42). Children and adults exposed to more than eight biological agents present in the home were at reduced risk of eczema (OR 0.17; 95% CI 0.04-0.77) and asthma (OR 0.49; 95% CI 0.25-0.97), respectively.

CONCLUSION

Exposure to a mildew/musty odour, as a proxy for exposure to fungus, was implicated in an increased risk of atopic diseases. Sensitisation may play a different role in children and adults, and exposure to multiple allergens may reduce the risk of atopic disease.

Relationship between respiratory and food allergy and evaluation of preventive measures

Food allergy and respiratory allergy are two frequently associated diseases and with an increasing prevalence. Several reports show the presence of respiratory symptoms in patients with food allergy, while certain foods may be related to the development or exacerbation of allergic rhinitis and asthma. The present update focuses on this relationship, revealing a pathogenic and clinical association between food and respiratory allergy. This association is even more intense when the food hypersensitivity is persistent or starts in the early years of life. Food allergy usually precedes respiratory allergy and may be a risk factor for allergic rhinitis and asthma, becoming a relevant clinical marker for severe atopic asthma. Furthermore, the presence of co-existing asthma may enhance life-threatening symptoms occurring during a food allergic reaction. Recommendations for dietary restrictions during pregnancy and breastfeeding to prevent the development of respiratory allergy are controversial and not supported by consistent scientific data. Current recommendations from medical societies propose exclusive breastfeeding during the first four months of life, with the introduction of solid food in the fourth to the seventh month period of life. A delayed introduction of solid food after this period may increase the risk of developing subsequent allergic conditions. Further studies are encouraged to avoid unjustified recommendations involving useless dietary restrictions.

Association of food allergy and atopic dermatitis exacerbations

BACKGROUND

Atopic dermatitis (AD) and food allergy frequently coexist in children.

OBJECTIVE

To examine the association between food allergy and AD.

METHODS

Between 2001 and 2011, children referred to our tertiary care center underwent double-blind, placebo-controlled food challenges (DBPCFCs) for one or more suspected food allergies as part of regular care. Immediate reactions were observed and recorded by allergy nursing staff, whereas late reactions were ascertained by semistructured telephone interview 48 hours after challenge. To test to which degree specific IgE results were predictive in the outcome of DBPCFCs in children with and without (previous and current) AD, logistic regression analysis was performed.

RESULTS

A total of 1186 DBPCFCs were studied. Sensitization to foods occurred significantly more often in children with previous AD. The association between specific IgE results and the outcome of DBPCFCs was significant for children with and without (previous and current) AD but stronger for children without current AD. The positivity rate of DBPCFCs in children with mild, moderate, and severe AD was 53.3%, 51.7%, and 100%, respectively. Children with AD and a history of worsening AD as their only symptom reacted as often to placebo as to challenge food.

CONCLUSION

Children with current AD are more frequently asymptomatically sensitized to the foods in question than those without AD. In addition, children suspected of food allergy should be considered for testing, regardless of the severity of their AD. Our results suggest that children with exacerbation of AD in the absence of other allergic symptoms are unlikely to be food allergic.

IgE antibodies in relation to prevalence and multimorbidity of eczema, asthma, and rhinitis from birth to adolescence

BACKGROUND

Eczema, asthma, and rhinitis affect a large proportion of children, but their prevalence varies with age. IgE antibodies are also common in the pediatric population. However, the links between IgE, disease, and trajectories are unclear.

OBJECTIVE

To better understand the links between sensitization and disease, we studied IgE sensitization ever in relation to eczema, asthma, and rhinitis, in children followed up to 16 years of age.

METHODS

From the Swedish population-based birth cohort BAMSE, 2607 children were included. Parental reports from six time points between 1 and 16 years were used to identify children with eczema, asthma, and rhinitis. Blood was collected at 4, 8, and 16 years, and sensitization ever was defined as allergen-specific IgE ≥0.35 kUA /l to common food and/or inhalant allergens at any time point. Odds ratios for eczema, asthma, rhinitis, and multimorbidity in relation to sensitization ever were calculated using generalized estimating equations.

RESULTS

Fifty-one percent were sensitized at least once up to 16 years. Almost a quarter of ever-sensitized children did not have any disease. After adjustment for potential confounders, sensitization ever was significantly associated with the following: (i) eczema throughout childhood, (ii) multimorbidity of eczema, asthma, and rhinitis from 1 to 16 years (OR for multimorbidity: 5.11, 95% CI: 3.99-6.55), (iii) asthma and rhinitis from 4 to 16 years of age.

CONCLUSIONS

Specific IgE is strongly associated with eczema and allergic multimorbidity throughout childhood and with asthma and rhinitis from age 4 years. However, 23% of the children with IgE sensitization do not develop any disease in childhood.

Incidence and risk factors for food hypersensitivity in UK infants: results from a birth cohort study

BACKGROUND

The prevalence of food hypersensitivity in the UK is still largely open to debate. Additionally its pathogenesis is also unclear although it is known that there are differing phenotypes. Determining its prevalence, along with identifying those factors associated with its development will help to assess its clinical importance within the national setting and also add to the debate on appropriate prevention strategies.

METHODS

A population based birth cohort study conducted in Hampshire, UK as part of the EuroPrevall birth cohort study. 1140 infants were recruited with 823 being followed up until 2 years of age. Infants with suspected food reactions were assessed including specific IgE measurement and skin prick testing. Diagnosis of food hypersensitivity was by positive double-blind, placebo-controlled food challenge (DBPCFC) where symptoms up to 48 h after the end of the food challenge were considered indicative of a food hypersensitivity. Factors associated with food hypersensitivity and its two phenotypes of IgE-mediated and non-IgE-mediated disease were modelled in a multivariable logistic regression analysis.

RESULTS

Cumulative incidence of food hypersensitivity by 2 years of age was 5.0 %. The cumulative incidence for individual food allergens were hens' egg 2.7 % (1.6-3.8); cows' milk 2.4 % (1.4-3.5); peanut 0.7 % (0.1-1.3); soy 0.4 % (0.0-0.8); wheat 0.2 % (0.0-0.5) and 0.1 % (0.0-0.32) for fish. The cumulative incidence of IgE-mediated food allergy was 2.6 % with 2.1 % reacting to hens' egg. For non-IgE-mediated food allergy the cumulative incidence was 2.4 % (cows' milk 1.7 %). Predictors for any food hypersensitivity were wheeze, maternal atopy, increasing gestational age, age at first solid food introduction and mean healthy dietary pattern score. Predictors for IgE mediated allergy were eczema, rhinitis and healthy dietary pattern score whereas for non-IgE-mediated food allergy the predictors were dog in the home, healthy dietary pattern score, maternal consumption of probiotics during breastfeeding and age at first solid food introduction.

CONCLUSIONS

Just under half the infants with confirmed food hypersensitivity had no demonstrable IgE. In an exploratory analysis, risk factors for this phenotype of food hypersensitivity differed from those for IgE-mediated food allergy except for a healthy infant diet which was associated with less risk for both phenotypes.

A clinical biomarker assay to quantitate thymic stromal lymphopoietin in human plasma at sub-pg/ml level

BACKGROUND

Thymic stromal lymphopoietin (TSLP) is an attractive therapeutic target for the treatment of allergic diseases, and plasma TSLP is a potential patient selection marker in the development of therapeutic agents.

RESULTS

We developed and validated an ultrasensitive electrochemiluminescence assay for measurement of TSLP in plasma with a lower limit of quantitation of 0.12 pg/ml, which allowed the quantitation of TSLP in approximately 90% of human plasma samples tested. The assay demonstrated excellent performance characteristics, including precision, accuracy, sensitivity and dilution linearity. Stability and biological variability of TSLP in plasma were also assessed for clinical sample analysis and data interpretation.

CONCLUSION

The validated TSLP assay enables assessment of circulating TSLP as a patient selection marker in the development of therapeutics to treat atopic diseases.

Food Allergy in Infants With Atopic Dermatitis: Limitations of Food-Specific IgE Measurements

BACKGROUND AND OBJECTIVES

Children with atopic dermatitis (AD) have a higher risk for development of food allergies. The objective of this study was to examine incidence of food allergy development in infants with AD and the predictive value of food-antigen-specific immunoglobulin E measurements.

METHODS

This trial examined the long-term safety and efficacy of pimecrolimus cream 1% in >1000 infants (3-18 months) with mild-to-severe AD without a history of food allergy. Food allergy development was followed throughout a 36-month randomized double-blind phase followed by an open-label (OL) phase up to 33 months. Additionally, sIgE for cow's milk, egg white, peanut, wheat, seafood mix, and soybean was measured by ImmunoCAP at baseline, end of the double-blind phase, and end of OL phase.

RESULTS

By the end of the OL phase, 15.9% of infants with AD developed at least 1 food allergy; allergy to peanut was most common (6.6%), followed by cow's milk (4.3%) and egg white (3.9%). Seafood, soybean, and wheat allergies were rare. Levels of sIgE for milk, egg, and peanut increased with severity of AD, as determined by Investigator's Global Assessment score. We assigned sIgE decision points for the 6 foods and tested their ability to predict definite food allergy in this population. Positive predictive values for published and newly developed sIgE decision points were low (<0.6 for all values tested).

CONCLUSIONS

In a large cohort of infants at risk for development of food allergy, sIgE levels were not clinically useful for predicting food allergy development.

The perception of allergen-specific immunotherapy among pediatricians in the primary care setting

BACKGROUND

Allergic respiratory diseases are constantly increasing in prevalence. Allergen Immunotherapy (AIT) represent a valuable therapeutic tool as symptomatic and preventative approach, expecially in children. In Italy, primary care pediatricians (PCP) represent the first-line contact and interface for prescription, use and management of AIT. We attempted to evaluate the perception of AIT practice among PCP.

METHODS

A questionnaire was built-up, based on literature, guidelines and with the contribution of pediatricians. The questionnaire, including 12 items, was e-mailed to 180 PCP, randomly chosen from mailing lists. The questionnaire explored the personal perception of AIT, the comparison between subcutaneous and sublingual AIT and the overall awareness about the treatment.

RESULTS

130 questionnaires were eligible for analysis. There was a satisfactory knowledge of the characteristics of AIT, its aims and limits, although the positioning of the treatment in guidelines was insufficiently known. Overall, the prescription of AIT made by other specialists was accepted and agreed (78 %). The majority of pediatricians felt that a more intense divulgation and information about AIT would be needed (90 %).

CONCLUSION

AIT is in general well known and accepted among PCP, although a more intense divulgation effort is required.

Evaluation of Serum Cytokines Levels and the Role of Cannabidiol Treatment in Animal Model of Asthma

Asthma represents a public health problem and traditionally is classified as an atopic disease, where the allergen can induce clinical airway inflammation, bronchial hyperresponsiveness, and reversible obstruction of airways. Studies have demonstrated the presence of T-helper 2 lymphocytes in the lung of patients with asthma. These cells are involved in cytokine production that regulates immunoglobulin synthesis. Recognizing that T cell interaction with antigens/allergens is key to the development of inflammatory diseases, the aim of this study is to evaluate the anti-inflammatory potential of cannabidiol (CBD) in this setting. Asthma was induced in 8-week-old Wistar rats by ovalbumin (OVA). In the last 2 days of OVA challenge animals received CBD (5 mg/kg, i.p.) and were killed 24 hours after. The levels of IL-4, IL-5, IL-13, IL-6, IL-10, and TNF-α were determinate in the serum. CBD treatment was able to decrease the serum levels of all analyzed cytokines except for IL-10 levels. CBD seems to be a potential new drug to modulate inflammatory response in asthma.

FLG P478S polymorphisms and environmental risk factors for the atopic march in Taiwanese children: a prospective cohort study

BACKGROUND

Little is known about the role of genetic and environmental modifiers in atopic march.

OBJECTIVE

To investigate the effects of filaggrin (FLG) P478S polymorphisms and environmental factors on the risk of asthma in a cohort of children with atopic dermatitis (AD).

METHODS

In 2010, 3,246 children from Childhood Environment and Allergic Diseases Cohort Study cohort were recruited. There were 485 children with AD who were invited for further clinical evaluation. Environmental exposures and skin prick tests for allergens were collected at 3 years of age and the development of asthma was determined at 6 years. Multivariate logistic regressions were performed to estimate the association between genetic and environmental factors and the development asthma in children with AD.

RESULTS

Of 397 children with AD who completed the follow-up, 97 developed asthma. After controlling for potential confounders, only mite sensitizations (odds ratio 1.89, 95% confidence interval 1.10-3.25) and the FLG TT genotype (odds ratio 2.26, 95% confidence interval 1.33-3.84) were significantly associated with the development of asthma in children with AD. Mite sensitizations and FLG variants had a synergistic effect on the development of asthma. When children with FLG variants were exposed to mite, the risk for asthma was compounded compared with those with FLG variants without mite exposure (odds ratio 3.58, 95% confidence interval 1.81-7.08).

CONCLUSION

Mite sensitization and the FLG TT genotype couldt be associated with the development of atopic march.

Rhinitis in the first 18 months of life: exploring the role of respiratory viruses

BACKGROUND

Rhinitis is common in early childhood, but allergic rhinitis is considered a later manifestation of the atopic march. This study aimed to evaluate rhinitis (allergic and non-allergic) in the first 18 months of life, its link with other atopic manifestations and the role of respiratory viruses.

METHODS

Subjects (n = 1237) of the Singapore GUSTO birth cohort were followed up quarterly until 18 months of age with questionnaires to screen for rhinitis symptoms lasting at least 2 wk and with monthly calls to positive subjects to detect prolonged/recurrent rhinitis symptoms (total duration ≥ 4 wk). Anterior nasal swabbing for molecular-based virus detection was conducted during these visits and near (within a month) rhinitis episodes. Skin prick testing to common environmental and food allergens was conducted at the 18 month visit.

RESULTS

Prolonged/recurrent rhinitis was significantly associated with history of parental atopy (mother: aOR = 2.17; father: aOR = 1.82) and atopic comorbidities of eczema (aOR = 2.53) and wheeze (aOR = 4.63) (p < 0.05), though not with allergen sensitization. Although the frequency of nasal respiratory virus detection during scheduled quarterly visits did not differ between prolonged/recurrent rhinitis and matched controls (p > 0.05), virus detection was higher in swabs obtained within a month following rhinitis episodes in prolonged/recurrent rhinitis subjects compared with scheduled visits (adjusted p = 0.04).

CONCLUSIONS

Based on the duration of rhinitis symptoms, this study defined a subset of early childhood rhinitis which was associated with atopic predisposition and comorbidities. Persistent respiratory viral shedding may contribute to the symptomatology. Whether this entity is a precursor of subsequent childhood allergic rhinitis will require longer follow-up.

Differences in Comorbidity Profiles between Early-Onset and Late-Onset Alopecia Areata Patients: A Retrospective Study of 871 Korean Patients

Background

Alopecia areata (AA) is a common dermatologic condition with a broad spectrum of clinical features and age of onset, classically characterized by nonscarring patches of hair loss. In the past, early-onset (before adolescence) AA has been associated with various autoimmune diseases, especially atopic diseases and lupus erythematosus and demonstrates a worse prognosis compared with late onset AA.

Objective

To evaluate the differences in the comorbidity profile of AA with regard to age at onset.

Methods

We completed a retrospective study of 871 Korean AA patients seen at our department within the last 10 years. After these patients were subdivided according to onset before or after age 13 years, the two groups were compared on the basis of their comorbid disorders, family history of AA, and hematologic test results.

Results

Our results demonstrate that significantly more patients in the early-onset group had a personal history of atopic dermatitis or family history of AA. These findings are consistent with previous reports associating early-onset AA with autoimmune diseases and a family history of AA in different ethnic populations. Most of the serologic test values showed no significant differences between the groups and the results were considerably affected by age.

Conclusion

This study is significant because it is a large group study in Korean AA patients, and Korean AA patients with an onset age before adolescence show similar clinical manifestations to other ethnic populations.

Probiotics in the prevention of eczema: a randomised controlled trial

OBJECTIVE

To evaluate a multistrain, high-dose probiotic in the prevention of eczema.

DESIGN

A randomised, double-blind, placebo-controlled, parallel group trial.

SETTINGS

Antenatal clinics, research clinic, children at home.

PATIENTS

Pregnant women and their infants.

INTERVENTIONS

Women from 36 weeks gestation and their infants to age 6 months received daily either the probiotic (Lactobacillus salivarius CUL61, Lactobacillus paracasei CUL08, Bifidobacterium animalis subspecies lactis CUL34 and Bifidobacterium bifidum CUL20; total of 10(10) organisms/day) or matching placebo.

MAIN OUTCOME MEASURE

Diagnosed eczema at age 2 years. Infants were followed up by questionnaire. Clinical examination and skin prick tests to common allergens were done at 6 months and 2 years.

RESULTS

The cumulative frequency of diagnosed eczema at 2 years was similar in the probiotic (73/214, 34.1%) and placebo arms (72/222, 32.4%; OR 1.07, 95% CI 0.72 to 1.6). Among the secondary outcomes, the cumulative frequency of skin prick sensitivity at 2 years was reduced in the probiotic (18/171; 10.5%) compared with the placebo arm (32/173; 18.5%; OR 0.52, 95% CI 0.28 to 0.98). The statistically significant differences between the arms were mainly in sensitisation to cow's milk and hen's egg proteins at 6 months. Atopic eczema occurred in 9/171 (5.3%) children in the probiotic arm and 21/173 (12.1%) in the placebo arm (OR 0.40, 95% CI 0.18 to 0.91).

CONCLUSIONS

The study did not provide evidence that the probiotic either prevented eczema during the study or reduced its severity. However, the probiotic seemed to prevent atopic sensitisation to common food allergens and so reduce the incidence of atopic eczema in early childhood.

TRIAL REGISTRATION NUMBER

ISRCTN26287422.

Cross-sectional comparison of the characteristics of respiratory allergy in immigrants and Italian children

BACKGROUND

Immigrants represent a good epidemiological model to evaluate the relative influence of environmental and inherited factors on the development of allergy. Several studies on allergy in adults have been published, but few data in children are available. We aimed to investigate the differences, between Italian and immigrant children, in clinical characteristics of respiratory allergy.

METHODS

This was a multicentre cross-sectional study involving children born in Italy from Italian parents and children born either in Italy or abroad from immigrants. Children referred firstly for allergic respiratory disease (rhinitis/asthma), with an ascertained clinical diagnosis and IgE sensitization to inhalants, were included. Demographic features, comorbidities, severity of disease, and sensitization profile were compared between Italians and immigrants, separating also those born in Italy from immigrant parents and those born abroad.

RESULTS

One hundred and sixty-five immigrant allergic children were enrolled (100 male, mean age 8.3 yr), 128 of whose had both parents immigrated. Italian children were 237 (156 male, mean age 8.4 yr). The Italian and immigrant children were similar, apart from pet's ownership and family size. There was no difference in the severity of rhinitis/asthma between the groups, whereas significant differences were found in the pattern of sensitization: immigrant children were more frequently sensitized to house dust mites (73.3% vs. 51%, respectively; p = 0.002) and less to grass (41.8% vs. 57.8%; p = 0.002); this was retained also in monosensitized children. Immigrant children born in Italy (n = 105) had a lower prevalence of rhinitis vs. Italians (68.3% vs. 87.6%, respectively, p = 0.003) and of sensitization to grass (28.3% vs. 49.5%, respectively, p = 0.008). No difference was found among macro-regions of origin and demographic or clinical features.

CONCLUSIONS

Immigrant children born either in Italy or abroad did not show significant differences in the clinical pattern of the respiratory allergic disease when compared to children born from Italian parents.

Severe eczema in infancy can predict asthma development. A prospective study to the age of 10 years

BACKGROUND

Children with atopic eczema in infancy often develop allergic rhinoconjunctivitis and asthma, but the term "atopic march" has been questioned as the relations between atopic disorders seem more complicated than one condition progressing into another.

OBJECTIVE

In this prospective multicenter study we followed children with eczema from infancy to the age of 10 years focusing on sensitization to allergens, severity of eczema and development of allergic airway symptoms at 4.5 and 10 years of age.

METHODS

On inclusion, 123 children were examined. Hanifin-Rajka criteria and SCORAD index were used to describe the eczema. Episodes of wheezing were registered, skin prick tests and IgE tests were conducted and questionnaires were filled out. Procedures were repeated at 4.5 and 10 years of age with additional examinations for ARC and asthma.

RESULTS

94 out of 123 completed the entire study. High SCORAD points on inclusion were correlated with the risk of developing ARC, (B = 9.86, P = 0.01) and asthma, (B = 10.17, P = 0.01). For infants with eczema and wheezing at the first visit, the OR for developing asthma was 4.05(P = 0.01). ARC at 4.5 years of age resulted in an OR of 11.28(P = 0.00) for asthma development at 10 years.

CONCLUSION

This study indicates that infant eczema with high SCORAD points is associated with an increased risk of asthma at 10 years of age. Children with eczema and wheezing episodes during infancy are more likely to develop asthma than are infants with eczema alone. Eczema in infancy combined with early onset of ARC seems to indicate a more severe allergic disease, which often leads to asthma development. The progression from eczema in infancy to ARC at an early age and asthma later in childhood shown in this study supports the relevance of the term "atopic march", at least in more severe allergic disease.

Correlation of ovalbumin of egg white components with allergic diseases in children

BACKGROUND

Immunoglobulin E (IgE)-mediated food allergy, such as egg white allergy, is common in young children (<3 years old), but not all young children sensitive to egg white present with allergic symptoms. This study investigated the relationship between sensitization to egg white component allergens and clinical manifestations of allergic diseases in young children.

METHODS

From March to December 2010, 2256 children with physician-diagnosed allergic diseases were tested for serum levels of egg white, ovalbumin, and ovomucoid-specific IgE in the Pediatric Allergy and Asthma Center of Chang Gung Memorial Hospital. Serum was analyzed for specific IgE antibodies to egg white, ovalbumin, and ovomucoid by ImmunoCAP (Phadia, Uppsala, Sweden). Allergen-specific IgE levels ≥0.35 kUA/L were defined as positive.

RESULTS

There was a significantly higher sensitization rate to egg white and its components in children aged 2-4 years old. The sensitization rate to egg white, ovalbumin, and ovomucoid in this age group was 53.5%, 48.3%, and 37.2%, respectively, and the trend of the sensitization decreased with age (p < 0.001). After adjusting for age, sensitization to egg white and ovalbumin was associated with children with dermatitis [egg white: odds ratio (OR) = 1.28, 95% confidence intervals (CI) = 1.03-1.58, p < 0.05; ovalbumin: OR = 1.30, 95% CI = 1.04-1.62, p < 0.05]. Children with ovomucoid sensitization had no statistically significant risk among different groups in the current study.

CONCLUSION

Children aged 2-4 years old have higher sensitivity to egg white, ovalbumin, and ovomucoid. Children with egg white and ovalbumin sensitization have a higher risk for atopic dermatitis, and ovalbumin has a more important contribution. Furthermore, we suggested that in children with atopic dermatitis, if they are aged 2-4 years old and are having egg white and ovalbumin sensitization, avoiding eating raw or slightly heated eggs might have a beneficial effect.

Systemic sensitization with the protein allergen ovalbumin augments local sensitization in atopic dermatitis

Mouse models of atopic dermatitis based on epicutaneous sensitization have shed light on the role of epicutaneous allergen entry in the development of respiratory and gastrointestinal allergy. However, the contribution of non-cutaneous modes of sensitization to skin diseases has not been evaluated. We assessed if systemic ovalbumin administration, in conjunction with local sensitization, could prime for a robust inflammatory response. Furthermore, we attempted to elucidate important aspects of disease pathogenesis previously unaddressed in mouse models. Mice that underwent intraperitoneal ovalbumin sensitization prior to epicutaneous challenge demonstrated an acute (Th2-polarized) atopic dermatitis-like phenotype upon local challenge. The inflammatory response was strikingly more robust than in mice that underwent epicutaneous sensitization alone. The lesional infiltrate contained a dendritic cell population that corresponded phenotypically with inflammatory dendritic epidermal cells of significance in human disease. Finally, in accordance with observations in human atopic dermatitis, there was an increase in cluster of differentiation (CD) 103 (α_E subunit)-expressing CD4⁺ T lymphocytes. However, the absence of CD103 on approximately 50% of infiltrating cells argues against a primary role for the α_Eβ₇ integrin in tissue homing. In conclusion, we present a mouse model of atopic dermatitis that reveals novel insights into the pathogenesis of this complex disease.

Effects of wheezing in early childhood in the development of allergic rhinitis in later years

BACKGROUND

Studies on the long-term effects of wheezing in infancy have particularly focused on asthma. There isn't adequate information about the effects of wheezing in the development of allergic rhinitis in later years.

OBJECTIVE

In this study, children with wheezing in the first year of life were investigated in terms of allergic rhinitis after five years of age.

METHODS

The study consisted of children with early-transient wheezing or persistent wheezing. The study groups were evaluated in terms of allergic rhinitis with physical examination and a questionnaire translated from International Study of Asthma and Allergies in Children (ISAAC) questionnaire after five years of age.

RESULTS

The study included 50 children; 23 (46%) had early-transient wheezing and 27 (54%) had persistent wheezing. The symptoms of allergic rhinitis were reported in 13 (48%) of children with persistent wheezing but in none of children with early-transient wheezing (p < 0.05). Skin prick tests showed positive results in 4.3% of children with early-transient wheezing and in 48.1% of children with persistent wheezing (p < 0.05).

CONCLUSION

Persistent wheezing, but not early transient wheezing seems to be a risk factor in the development of allergic rhinitis in children after five years of age.

Single parent households and increased child asthma morbidity

OBJECTIVES

To characterize whether single parent households are associated with pediatric asthma-related repeat healthcare utilization and to examine family-level psychosocial variables that may explain this relationship.

METHODS

We analyzed a prospective cohort of 526 children aged 1-16 years hospitalized for asthma or bronchodilator-responsive wheezing whose caregivers self-reported their marital status. Those reporting being "single" were considered the at-risk category. The outcome was repeat asthma-related utilization (emergency room (ER) revisit or hospital readmission) within 12 months. We assessed, a priori, four psychosocial variables (household income, caregiver risk of psychological distress, ratio of in-home children to adults, and regular attendance at childcare or a secondary home).

RESULTS

Among all children enrolled in the cohort, 40% returned to the ER or hospital for asthma within 12 months. Of all caregivers, 59% self-identified as single. Single status was significantly associated with each psychosocial variable. Children in households with lower incomes and higher ratios of children to adults were both more likely to return to the ER or hospital than children with higher incomes and lower ratios, respectively (each p < 0.05). Patients in single parent households were significantly more likely to reutilize than those in married parent households (OR 1.44, 95% CI 1.00-2.07, p < 0.05). When adjusted for income, the relationship between single parent households and reutilization became non-significant.

CONCLUSIONS

Children admitted for asthma from single parent households were more likely to have asthma-related reutilization within 12 months than children from homes with married parents. This was driven, in large part, by underlying differences in household income.

Risks of new-onset allergic sensitization and airway inflammation after early age swimming in chlorinated pools

RATIONALE

Irritant chlorination products in swimming pools can cause respiratory problems in swimmers but their possible implication in allergies development is still unclear.

OBJECTIVES

To assess prospectively whether early-life attendance at chlorinated pools increases the risks of IgE sensitization and of airways inflammation later during childhood.

METHODS

We conducted a two-year prospective study among 196 kindergarten children (mean age of 5.7 years, 54% of boys). We measured exhaled nitric oxide (eNO) and aeroallergen-specific IgE in nasal mucosa. Parents completed a questionnaire about the child's health, chlorinated pool attendance and potential confounders.

MAIN RESULTS

Ever swimming at indoor or outdoor chlorinated pools before the age of three years was associated with higher odds for new-onset IgE sensitization to house dust mite (adjusted odds ratio [aOR] 2.93, 95% confidence interval [CI] 1.14-7.55) and for new-onset increased eNO (>15 ppb; aOR, 4.54, 95% CI 1.48-13.9). For both outcomes, aORs increased dose-dependently with time spent in chlorinated pools with values reaching, respectively, 3.60 (95% CI 1.21-10.7) and 5.92 (95% CI 1.72-20.5) when the cumulative pool attendance exceeded 60 h These risks appeared independently of each other, of parental history of allergies and of pre-existing diseases, including eczema, which at baseline was more prevalent in early swimmers (aOR, 2.91; 95% CI 1.23-6.89). Such associations were not seen with IgE sensitization to pollen or cat allergens.

CONCLUSION

Attendance at chlorinated swimming pools in early life is associated with higher risks of new-onset airways inflammation and IgE sensitization to house dust mite, independently of other risk factors.

Why patients visit their doctors: assessing the most prevalent conditions in a defined American population

OBJECTIVE

To describe the prevalence of nonacute conditions among patients seeking health care in a defined US population, emphasizing age, sex, and ethnic differences.

PATIENTS AND METHODS

The Rochester Epidemiology Project (REP) medical records linkage system was used to identify all residents of Olmsted County, Minnesota, on April 1, 2009, who had consented to review of their medical records for research (142,377 patients). We then electronically extracted all International Classification of Diseases, Ninth Revision codes noted in the records of these patients by any health care institution between January 1, 2005, and December 31, 2009. We grouped International Classification of Diseases, Ninth Revision codes into clinical classification codes and then into 47 broader disease groups associated with health-related quality of life. Age- and sex-specific prevalence was estimated by dividing the number of individuals within each group by the corresponding age- and sex-specific population. Patients within a group who had multiple codes were counted only once.

RESULTS

We included a total of 142,377 patients, 75,512 (53%) of whom were female. Skin disorders (42.7%), osteoarthritis and joint disorders (33.6%), back problems (23.9%), disorders of lipid metabolism (22.4%), and upper respiratory tract disease (22.1%, excluding asthma) were the most prevalent disease groups in this population. Ten of the 15 most prevalent disease groups were more common in women in almost all age groups, whereas disorders of lipid metabolism, hypertension, and diabetes were more common in men. Additionally, the prevalence of 7 of the 10 most common groups increased with advancing age. Prevalence also varied across ethnic groups (whites, blacks, and Asians).

CONCLUSION

Our findings suggest areas for focused research that may lead to better health care delivery and improved population health.

Future therapies for food allergy

Food allergy affects 3.9% of US children and is increasing in prevalence. The current standard of care involves avoidance of the triggering food and treatment for accidental ingestions. While there is no current curative treatment, there are a number of therapeutic strategies under investigation. Allergen specific therapies include oral and sublingual immunotherapy with native food protein as well as recombinant food proteins. Allergen non-specific therapies include a Chinese herbal formula (FAHF-2) and the use of anti-IgE monoclonal antibody therapy. Although none of these treatments are ready for clinical use, these therapeutic strategies present promising options for the future of food allergy.

The IgE repertoire in children and adolescents resolved at component level: a cross-sectional study

BACKGROUND

It is well known that allergy evolves at clinical level from the birth to adulthood, and this has been clearly demonstrated also at a level of sensitization. However, little information is available on the evolution of the IgE repertoire directed to single allergenic components. In this cross-sectional, observational study, the evolution of the IgE repertoire was analysed at component level.

METHODS

Serum samples from 901 allergic patients, stratified in 6 groups according to age, were analysed by ImmunoCAP ISAC, a microarray chip that allows to identify the presence of specific IgE towards 103 different allergen components. Total IgE were also evaluated.

RESULTS

The behaviour of total IgE according to age strictly paralleled that of the sum of specific IgE directed to molecular components. As expected, food-related components (in particular those of milk and egg) were the most frequently recognized in the earliest ages, whereas specific IgE to plant allergens appeared invariably later. Nonetheless, IgE specific to mite components was the most represented in all age classes. Of note, specific IgE against cross-reacting allergens was virtually absent in the first years and tended to appear only after the age of 6.

CONCLUSION

Despite this was not a study performed on a cohort of patients followed up from birth to adolescence, the molecular patterns of allergen recognition resulted modified according to age. These findings may support, at molecular level, the clinical features of the allergic march.