Atopic Children Research Articles

The Role of TSLP and IL-1 β and Their Genetic Variants in the Pathogenesis of Single and Multiple Atopic Diseases in Children.

Allergic diseases commonly coexist, manifesting in a sequence described as the "allergic march". Background/Objectives: This study aimed to evaluate TSLP's and IL-1β's potential as biomarkers in both single and multi-pediatric atopic diseases like atopic eczema, food allergy, and anaphylaxis and analyze specific SNPs in the TSLP and IL-1β genes to determine their associations with their occurrence and severity. Methods: This analysis included 109 atopic children diagnosed with atopic dermatitis, food allergy, or anaphylaxis alongside a control group of 57 non-atopic children. Recruitment was facilitated through the use of a comprehensive questionnaire. For the study population, the allergen profile was characterized at the molecular level by measuring specific IgE to purified natural or recombinant allergens, assessing serum levels of circulating TSLP and IL-1β, and identifying single-nucleotide polymorphisms in TSLP (rs2289277) and IL-1β (rs16944 C-511T). Results: The serum levels of TSLP and IL-1β were elevated in the study groups compared to the control group, highlighting their significance in the pathogenesis of the studied diseases. Carrying a higher number of the risk allele [C] in the TSLP SNP rs2289277 is associated with the greatest likelihood of having multiple concurrent allergic conditions, with the highest risk observed in individuals with all three conditions-atopic dermatitis, food allergy, and anaphylaxis, simultaneously. Moreover, children carrying the risk allele had a twofold increased risk of polysensitization, which rose to sixfold in those with two copies of the risk allele. Although no significant variations in genotype frequencies were detected for IL-1β rs16944, significant associations were observed for TSLP rs2289277, particularly with conditions such as atopic dermatitis, food allergy, anaphylaxis, and combinations of these diseases. Conclusions: Further research is required to elucidate these pathways and their role in the development of allergic diseases.

Birthing parent adverse childhood experiences and risk of atopic diseases in 5-year-old children.

Following up on previous findings from the All Our Families (AOF) cohort, the current study investigated the relationship between birthing parent history of adverse childhood experiences (ACEs) and child atopy, including asthma, allergy, and eczema, at five years of age. Potential indirect effects were explored. Participants completed the ACEs scale, validated questionnaires of anxiety and depression symptoms, and reported on their and their children's atopic disease history. Archival analyses of AOF data (N = 3,387) was conducted using logistic regression and path analysis with counterfactually based indirect effects. Birthing parent history of ACEs was associated with an 18% increased risk of child allergy at five years (OR = 1.18, 95% CI: 1.09, 1.20). Exploratory path analyses indicated a significant indirect effect of ACEs through birthing parent history of atopy on child asthma, allergy, and eczema at five years. There were no significant indirect effects through birthing parent symptoms of anxiety or depression during pregnancy, at two or five years postpartum. Birthing parent history of ACEs, combined with birthing parent history of atopy, may elevate the risk of child atopy. This presents an opportunity for early intervention for children at risk of atopic disease.

Low glycaemic index diet in pregnancy and child asthma: follow-up of the ROLO trial.

Epidemiological evidence suggests that a higher intake of sugar during pregnancy is associated with a higher risk of childhood asthma and atopy. However, randomised trial evidence supporting such a link is lacking. This study aimed to examine whether a low glycaemic index (GI) dietary intervention during pregnancy decreases the risk of childhood asthma and eczema. This is a secondary analysis of 514 children from the ROLO trial. Healthy women were randomised to receive an intervention of low GI dietary advice or routine care from early pregnancy. Mothers reported current doctor-diagnosed eczema in their children at 2 years (n 271) and current doctor-diagnosed asthma and eczema in their children at 5 (n 357) and 9-11 years (n 391) of age. Multivariable logistic regression models were used test the effect of the intervention on child outcomes overall and stratified by maternal education. There was a suggestion of a reduction in asthma at 5 years of age in children whose mothers received the low GI dietary intervention during pregnancy compared with usual care (adjusted OR 0·46 (95 % CI 0·19, 1·09); P = 0·08). In stratified adjusted analyses, the intervention was associated with a reduced risk of asthma at 5 years of age in children born to mothers with incomplete tertiary level education but not in those with complete tertiary level education (OR 0·14 (95 % CI 0·02, 0·69); P = 0·010 and OR 1·03 (95 % CI 0·34, 3·13); P = 0·94, respectively). A low GI diet in pregnancy may reduce the risk of developing asthma in childhood, particularly amongst children born to mothers with lower educational attainment.

Networks of human milk microbiota are associated with host genomics, childhood asthma, and allergic sensitization

The human milk microbiota (HMM) is thought to influence the long-term health of offspring. However, its role in asthma and atopy and the impact of host genomics on HMM composition remain unclear. Through the CHILD Cohort Study, we followed 885 pregnant mothers and their offspring from birth to 5 years and determined that HMM was associated with maternal genomics and prevalence of childhood asthma and allergic sensitization (atopy) among human milk-fed infants. Network analysis identified modules of correlated microbes in human milk that were associated with subsequent asthma and atopy in preschool-aged children. Moreover, reduced alpha-diversity and increased Lawsonella abundance in HMM were associated with increased prevalence of childhood atopy. Genome-wide association studies (GWASs) identified maternal genetic loci (e.g., ADAMTS8, NPR1, and COTL1) associated with HMM implicated with asthma and atopy, notably Lawsonella and alpha-diversity. Thus, our study elucidates the role of host genomics on the HMM and its potential impact on childhood asthma and atopy.

Serum leptin and adiponectin function as indicators of allergic sensitization in pediatric adenotonsillar hypertrophy.

Obesity is commonly linked to both adenotonsillar hypertrophy (ATH) and allergic disorders, in which the roles of adipokines are not fully illuminated. This study aims to investigate the levels of leptin and adiponectin and their associations with allergic sensitization in pediatric ATH. Serum levels of specific immunoglobulin E (IgE), leptin and adiponectin were quantified in 35 controls and 111 ATH children, in which 54 were non-atopic and 57 were atopic. Spearman's correlation analysis and polynomial linear trend test were conducted. The odds ratios and 95% confidence intervals were calculated by binary logistic regression after multivariable adjustment. The serum level of leptin and leptin/adiponectin (L/A) ratio was significantly increased in children with ATH. An increase in leptin level and L/A ratio and a decrease in adiponectin level were observed in atopic children compared with non-atopic children. Among ATH children, the level of adiponectin was negatively while L/A ratio was positively correlated with specific IgE. After multivariable adjustment, leptin was significantly associated with increased risk of atopy to D. pteronyssinus and D. farina, and adiponectin was significantly associated with decreased risk of atopy to willow and mugwort. Leptin was associated with higher odds while adiponectin was associated with lower odds of overall atopy. Besides, significant multiplicative interactions of obesity with leptin and adiponectin on atopy were observed respectively. Leptin and adiponectin were both associated with allergic sensitization and function differently in pediatric ATH. Mechanistic studies are needed to elucidate the involvement of adipokines in allergic sensitization of pediatric ATH.

The complicated relationship between asthma and swimming

Introduction: Apart from pharmacological treatment, non-pharmacological strategies including physical activity play a significant role in the management of asthma. The aim of this paper is to examine various topics related to swimming and asthma. They include the detailed effect of swimming on asthma control,the potential role of swimming in early childhood asthma development, exercise induced asthma in swimmers as well as the relationship between asthma and cold water swimming. Review methods: This article is based on the literature found in the PubMed Database from the period of 1971-2024 with the use of keywords such as “asthma”, “swimming”, “cold water swimming”, “exercise induced asthma”, “childhood asthma” Description of the state of knowledge: Swimming is a safe form of physical activity for asthma patients.Swimming training enhances aerobic capacity, reduces exercise-induced bronchoconstriction and improves lung function in both pediatric and adult patients. However, there is a concern regarding indoor swimming pools that chlorine can potentially induce airway inflammation. There is research suggesting that early life swimming pool exposure may contribute to the asthma development in atopic children. There is some premise to the thought that cold water swimming may help alleviate asthma symptoms, but it also carries many risks.Swimming is a major cause of exercise induced asthma in professional athletes. Conclusions: Alongside appropriate pharmacological treatment, swimming is a valuable strategy in asthma management in both pediatric and adult asthma patients. The risks of chlorinating pools are still not known to outweigh the benefits of swimming for asthmatics. Further research should be carried out on safety of early swimming in atopic children. Cold water swimming should also be evaluated in terms of safety and potential benefits for asthma patients.

Analyzing Racial Disparities in Pediatric Atopic Comorbidity Emergency Department Visitation Using Electronic Health Records

BackgroundAlthough atopic diseases and associated co-morbidities are prevalent in children, little is known about racial differences in emergency department (ED) visitation. ObjectiveWe sought to examine racial differences in ED visitation among children with allergic comorbidities. MethodsWe conducted a retrospective study of patients (<21 years) who visited the ED at a large pediatric hospital for atopic dermatitis (AD), food allergy (FA), asthma, allergic rhinitis (AR), and eosinophilic esophagitis (EoE) from 2015 to 2019. We determined the probability of ED encounter-free using hazard ratios (HR) and time to recurrence (TTR) of ED encounter for patients identified as Black/African American (AA) and White/European American (EA). We assessed potentially underlying allergic, demographic, and place-based factors, and potential interactions between factors. ResultsA total of 30,894 patients (38% AA, 62% EA) had 83,078 ED encounters (38,378 first ED encounters, and 44,700 recurrent ED encounters) during the study period. Asthma and AR showed the highest rate of comorbidity in ED encounters in both AA and EA children. AA children exhibited higher HR for encounter following index AD and asthma encounters. We found an interaction between the type of insurance and race in ED encounters for AD, FA, AR, and EoE. In AA children, those insured by Medicaid demonstrated a higher HR for any encounter compared to those with commercial insurance. Conversely, in EA children, those with Medicaid insurance showed a lower HR compared to their commercially insured peers. Regardless of race, allergic comorbidity increased the HR of ED encounter (1.12-1.62) for all allergic diseases. At 5-years follow up, mean differences in TTR were shorter in AA children compared to EA children in AD, FA, and asthma. ConclusionIdentification of disease-specific racial disparities in ED visitation related to atopic diseases is a necessary first step toward the design and implementation of interventions capable of equitably reducing emergency care in atopic comorbid children.

Low glycaemic index diet in pregnancy and child asthma and eczema: follow-up of the ROLO trial

Atopic diseases, including asthma and eczema, represent a substantial public health problem in children and adolescents globally; asthma is the commonest chronic disorder of childhood(1). Research suggests that the origins of childhood asthma lie in utero, and several components of the maternal diet during pregnancy have been investigated in relation to atopic outcomes in children. Epidemiological evidence suggests that a higher intake of sugar during pregnancy is associated with a higher risk of childhood asthma and atopy(2,3). However, randomised trial evidence supporting such a link is lacking.Aims 1.To examine whether a low glycaemic index (GI) dietary intervention during pregnancy decreases the risk of asthma and eczema in childhood.2.To assess observationally whether maternal intake of sugar during pregnancy is positively associated with asthma and eczema in childhood.This is a secondary analysis of children from the ROLO trial. Healthy women were randomised to receive an intervention of low GI dietary advice or routine antenatal care from early pregnancy. All women completed a 3-day food diary in each trimester of pregnancy. Estimates of maternal intake of sugar in each trimester were averaged to provide mean intakes during pregnancy. Mothers reported current doctor-diagnosed eczema in their children at 2-years of age (n=271), and current doctor-diagnosed asthma and eczema in their children at 5 (n=357) and 9-11 years (n=391) of age. Multivariable logistic regression models were used a) to test the effect of the intervention on child outcomes overall, and stratified by maternal education level (with, versus without, a complete tertiary level education), and b), in observational analyses, to analyse the relation between sugar and carbohydrate intake in pregnancy and child outcomes.There was weak evidence overall for a reduction in asthma at 5-years of age in children whose mothers received the low GI dietary intervention during pregnancy compared to usual care [adjusted odds ratio (OR) 0.43 (95% CI 0.18, 1.03); P=0.06]. However, in stratified analyses the intervention was associated with a marked reduction in risk of asthma at 5-years of age in children born to mothers with lower educational attainment [adjusted OR 0.16 (0.03, 0.85); P=0.032]. Intake of sugar during pregnancy was positively associated with the development of asthma at any time point in childhood [adjusted OR per quartile of mean sugar intake 1.40 (0.99, 1.97), P-trend=0.048] and at 5-years of age [adjusted OR per quartile 1.55 (1.00, 2.40), P-trend=0.046]. No associations with eczema outcomes were found.This novel study provides stronger evidence that higher sugar intake during pregnancy is associated with an increased risk of asthma among offspring. An intervention to reduce sugar intake in pregnancy may have potential as a primary prevention strategy, particularly amongst children born to mothers with lower educational attainment.

Quand mettre en route un traitement systémique dans la dermatite atopique ?

Despite the advent of numerous new treatments for atopic dermatitis, many patients, both adults and children, are still on treatment errands and are not receiving sufficient treatment to control their disease in the long term. It is therefore important to identify patients who need systemic treatment when topical treatments are no longer suitable. The decision to initiate a systemic treatment must be based on several factors that go well beyond the marketing authorisation and reimbursement of a drug. This approach involves a multidimensional assessment of the disease’s severity, in which scores have a place if they are feasible in practice and if they take into account the patient’s perception of their symptoms and the impact of the disease on their quality of life. Shared decision-making means that the expectations of the doctor and the patient (or the patient’s family in the case of children) can be harmonised, and a suitable and realistic therapeutic objective can be defined in a collaborative manner. Identifying a patient eligible for systemic treatment at an early stage requires appropriate training in primary care (general practitioner or paediatrician) and a good city-hospital cooperation for the dermatologist or allergist in order to facilitate the patient pathway and guarantee access to «the right treatment at the right time».

Does Molluscum Contagiosum Need to be Managed Differently in Atopic Children?

The association between molluscum contagiosum and concomitant atopic dermatitis and its impact on clinical features and treatment outcomes remains unclear. This retrospective study, conducted in the paediatric dermatology clinic of a tertiary medical centre, aimed to compare molluscum patients with and without atopic dermatitis. A total of 615 children with molluscum were included, 13.17% of whom had atopic dermatitis. While the latter group exhibited higher lesion count and itchiness (p=0.026 and p=0.044, respectively), no significant differences were observed in average lesion diameter, ulceration, purulence, and erythema (p=0.239, p=0.730, p=0.682, and p=0.296, respectively). Both groups showed comparable responses to molluscum-specific and supportive treatments, with no distinct difference in outcomes or recurrence of visits. It was concluded that atopic dermatitis does not exacerbate molluscum morbidity, inflammation markers, treatment outcomes or recurrence rates.

Prevalence and Severity of COVID-19 among Pediatric Patients with Atopy: A Cross-sectional Study in Kerman, Southeast Iran.

The tragic COVID-19 pandemic affected many children worldwide. Among the factors that may influence the course of viral infections including COVID-19, it is still uncertain whether atopy has a protective or predisposing role. The study aims to address the knowledge gap by investigating the prevalence and severity of COVID-19 among atopic children in Kerman, in 2022. A descriptive-analytical cross-sectional study on children with a history of atopy was performed in Kerman Medical University. Demographic information, type of atopy (including allergic rhinitis, Hyper-Reactive Airway Disease (HRAD) or asthma, eczema, urticaria, anaphylaxis, and food allergy), history of COVID-19 infection, and disease severity were recorded. A total of 1007 children and adolescents, (boys: 56.4%, girls: 43.6%, age:5.61±2.64 years) were included in the study. History of COVID-19 infection was positive in 53.5%, with 75.9% of the cases exhibiting mild disease severity. The frequency of atopies was HRAD or asthma (67.2%), allergic rhinitis (42.6%), and food allergy (27.4%). The frequency of COVID-19 cases was significantly higher among patients with HRAD or asthma, whereas it was significantly lower among those with food allergies, anaphylaxis, and eczema. Among atopic individuals, COVID-19 severity was significantly lower in those with allergic rhinitis, while the opposite trend was observed among food-allergic individuals. This study sheds light on the relationship between atopy and COVID-19 among pediatric patients. It seems specific types of atopies may influence the risk and severity of COVID-19 infection differently. A better understanding of these associations can inform clinical management and preventive measures for vulnerable pediatric populations.

Improved childhood asthma control after exposure reduction interventions for desert dust and anthropogenic air pollution: the MEDEA randomised controlled trial

IntroductionElevated particulate matter (PM) concentrations of anthropogenic and/or desert dust origin are associated with increased morbidity among children with asthma.ObjectiveThe Mitigating the Health Effects of Desert Dust Storms Using Exposure-Reduction...

Maternal mental health disorders and offspring asthma and allergic diseases: The role of child mental health.

Maternal psychological stress during pregnancy and postnatally has been shown to be associated with offspring atopic diseases (asthma, atopic dermatitis and allergic rhinitis). The aim of this study was to assess whether this association may be attributable to the child's own mental health disorders. The study population included 15,092 twin children born 2002-2010 in Sweden. Questionnaire data at age 9 years was linked to national patient- and prescription registers. Maternal mental health during pregnancy and 3 years postnatally were identified from diagnosis and medication data (depression, anxiety and stress disorders). Atopic diseases in children were identified from questionnaires, diagnosis and medication data. Child mental health status (depression and anxiety) was identified from questionnaires. Three-way decomposition methods tested for mediation or interaction by child mental health disorders. Maternal mental health disorders were associated with most child atopic diseases including asthma aRR1.36 (95% CI 1.12, 1.60), and child mental health disorders, aRR1.73 (95% CI 1.56, 1.92). Children with mental health disorders were comorbid for atopic diseases with only asthma reaching statistical significance, aRR1.29 (95% CI 1.14, 1.47). Three-way decomposition found that mediation or interaction by child mental health disorders did not account for the mother mental health and child atopy associations except in parent-report asthma, where child mental health disorders mediated 13.4% (95% CI 2.1, 24.7) of the effect, but not for objectively defined (diagnosis and medication) asthma. The associations between maternal mental health and child asthma and allergic diseases do not appear to be attributable to child mental health disorders.

Association between Breastfeeding and Development of Atopy

Objective: This study aimed to investigate the relationship between breastfeeding and the development of atopy. Methods: A hospital-based cross-sectional study was conducted in the pediatrics and obstetrics/gynecological clinics&amp;apos; waiting areas and admission wards of the Maternity and Children Hospital in Hail region, between November 2022 and February 2023, targeting mothers with at least one child over the age of one month. Results: A sample of 423 children from Hail was studied in the current research. Most of them were over 12 months old. Although most of the participants believed that breastfeeding reduced the incidence of atopic skin disease, the most prevalent type of feeding was formula feeding, followed by mixed feeding and exclusive breastfeeding. The study showed no significant effects of breastfeeding type on the development of allergies in children, as well as breastfeeding type and duration. However, there was a significant association between formula feeding and the development of allergic rhinitis, as it increases the incidence. Conclusion: The findings of this study demonstrated that no definitive link could be made between breastfeeding duration and the development of atopy or between breastfeeding type and the occurrence of atopy in children. However, the study showed that formula feeding was a significant risk factor for the development of allergic rhinitis.

Sleep improvements following atopic dermatitis management in young children

The purpose of this pilot study was to assess improvements in associated sleep and caregiver mood following treatment of atopic dermatitisin young children. Participants included children (n=23; Mage =22.0months) and their caregivers. Topical management of atopic dermatitis was conducted for 2 weeks, with measures of skin, sleep (child, caregiver), and mood (caregiver) at baseline and day 14. Topical management resulted in significant improvements in child skin, with associated increases in sleep consolidation. There were similar improvements in caregiver nightwakings, with nighttime sleep duration improving by over an hour. Caregivers also reported more energy to engage with their family and feeling better rested. Overall, topical management significantly improved atopic dermatitis. There were concomitant improvements in sleep outcomes for children and their caregivers, as well as caregiver mood. Daily management of atopic dermatitis may result in improvements in not just skin health but also sleep and family well-being.

Spectra of sensitization to aeroallergens in patients with allergy from the upper chirchik district of the Republic of Uzbekistan

BACKGROUND: Allergic airway diseases caused by hypersensitivity to aeroallergens are the most common manifestation of atopy in children and adults. However, sensitization in the population primarily depends on the allergenic composition of the air environment. Identification of sensitization is a prerequisite for successful treatment of allergic diseases, although the structure of sensitization may have regional characteristics. AIM: To study the spectrum of sensitization in people with allergic diseases, namely, allergic rhinitis, bronchial asthma of varying severity, and atopic dermatitis, in the Upperchirchik district of the Tashkent region, which is characterized by a long period of flowering of weeds (wormwood, saltwort, and quinoa, from the end of August to the end of November), cereals (timothy, foxtail, rye, and bluegrass), and herbs (from the end of February to the end of July); the duration of flowering is associated with the peculiarities of climatic and geographic conditions. MATERIALS AND METHODS: From January to May 2022, a clinical and allergological examination was conducted on 100 patients with allergic diseases; of these, 38 were children aged 2–18 years (including 20 children with allergic rhinitis, 12 with bronchial asthma, 6 with atopic dermatitis) and 62 were adults (including 32 patients with allergic rhinitis, 13 with bronchial asthma, 17 with atopic dermatitis). To study the total IgE in the blood serum, allergen-specific IgE and standard diagnostic allergens were used for skin testing. RESULTS: Among all examined patients, the most frequent were intermittent and persistent forms of allergic rhinitis in 52 (52%), bronchial asthma in 25 (25%), atopic dermatitis in 23 (23%), combination of allergic rhinitis + bronchial asthma in 13 (13%), allergic rhinitis + atopic dermatitis in 12 (12%), and atopic dermatitis + bronchial asthma in 9 (9%) patients. Combined sensitization to pollen and household and food allergens was detected in 90% of the patients, monosensitization to allergens of cereal grasses (meadow Timothy and meadow bluegrass) in 6% and to allergens of weeds (wormwood and quinoa) in 4%. Sensitization to house dust (h1) was detected in 29 children and 51 adults. The frequency of sensitization to food allergens was higher in children than in adults: to cow’s milk allergens in 28.9% of children and 8.1% of adults; to egg allergens in 44.7% of children and 24.2% of adults; and to nut allergens in 38.7% of children and 34.2% of adults. CONCLUSION: The spectrum of sensitization to allergens in patients with allergic diseases in the Upperchirchik district of the Tashkent region is characterized by a predominance of sensitization to pollens and household allergens in children and adults, with a significant proportion of polysensitized patients in all age groups.

The Association of Prenatal C-Reactive Protein Levels With Childhood Asthma and Atopy.

The Association of Prenatal C-Reactive Protein Levels With Childhood Asthma and Atopy.

Patch Testing in Atopic Children: Is There a Difference?

Patch Testing in Atopic Children: Is There a Difference?

Atopic March in Children: A Case Report and Review of Current Literature

Background: The concept of atopic march was introduced about 15 years ago to define the temporal progression of different allergic conditions, from atopic dermatitis and food allergies in earliest childhood to the development of asthma and allergic rhinitis in older children. Case Presentation: The authors describe a case report of a young girl who went through the stages of atopic march. The child first showed atopic dermatitis and food allergy in infancy, and, after-wards, she manifested allergic rhinitis and asthma in childhood. Discussion: This timeline reflects the atopic march's spatial evolution, beginning with the skin and gastrointestinal tract and progressing to the upper and lower airways. Conclusion: In accord with the most recent evidence, rather than being defined in terms of chrono-logical progression, atopic diseases should be investigated as a spectrum of atopic disorders that might take various developmental paths. According to this theory, the use of Component Resolved Diagnosis in atopic children can be beneficial for highlighting and predicting the atopic profile du-ring the earliest years of life before symptoms arise, helping to stratify the clinical risk and preven-ting the onset of the atopic march and severe responses.

The link between early childhood lower airway symptoms, airway hyperresponsiveness, and school-age lung function

BackgroundThe role of early airway hyperresponsiveness (AHR) in the lung function of school-age children is currently unclear. ObjectiveTo conduct a prospective follow-up study of lung function in schoolchildren with a history of lower airway symptoms and AHR to methacholine in early childhood and to compare the findings to schoolchildren with no previous or current lung diseases. We also explored symptoms and markers of type 2 inflammation. MethodsIn 2004 to 2011, data on atopic markers, lung function, and AHR to methacholine were obtained from 193 symptomatic children under 3 years old. In 2016 to 2018, a follow-up sample of 84 children (median age, 11 years; IQR, 11-12) underwent measurements of atopic parameters, lung function, and AHR to methacholine. Moreover, in 2017 to 2018, 40 controls (median age, 11 years; IQR, 9-12) participated in the study. ResultsSchoolchildren with early childhood lower airway symptoms and increased AHR had more frequent blood eosinophilia than their peers without increased AHR and lower prebronchodilator forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity Z-scores than those without increased AHR and controls. Post-bronchodilator values were not significantly different between the two AHR groups. Atopy in early childhood (defined as atopic eczema and at least 1 positive skin prick test result) was associated with subsequent lung function and atopic markers, but not AHR. ConclusionIn symptomatic young children, increased AHR was associated with subsequent obstructive lung function, which appeared reversible by bronchodilation, and blood eosinophilia, indicative of type 2 inflammation.