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Background: Longitudinal population-based data regarding tree nut allergy are limited., Objectives: We sought to determine the population prevalence of tree nut allergy at age 6 years and explore the relationship between egg and peanut allergy at age 1 year and development of tree nut allergy at age 6 years., Methods: A population-based sample of 5276 children was recruited at age 1 year and followed up at age 6 years. At age 1 year, allergies to egg and peanut were determined by means of oral food challenge, and parents reported their child's history of reaction to tree nuts. Challenge-confirmed tree nut allergy was assessed at age 6 years., Results: At age 1 year, the prevalence of parent-reported tree nut allergy was 0.1% (95% CI, 0.04% to 0.2%). Only 18.5% of infants had consumed tree nuts in the first year of life. At age 6 years, challenge-confirmed tree nut allergy prevalence was 3.3% (95% CI, 2.8% to 4.0%), with cashew the most common (2.7%; 95% CI, 2.2% to 3.3%). Of children with peanut allergy only at age 1 year, 27% (95% CI, 16.1% to 39.7%) had tree nut allergy at age 6 years compared with 14% (95% CI, 10.4% to 17.9%) of those with egg allergy only and 37% (95% CI, 27.2% to 47.4%) of those with both peanut and egg allergy., Conclusions: Tree nut allergy is uncommon in the first year of life, likely because of limited tree nut consumption. At age 6 years, tree nut allergy prevalence is similar to peanut allergy prevalence. More than a third of children with both peanut and egg allergy in infancy have tree nut allergy at age 6 years. Understanding how to prevent tree nut allergy should be an urgent priority for future research., (Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: A recent randomized trial (the Learning Early About Peanut Allergy [LEAP] study) provided evidence that earlier dietary peanut introduction reduces peanut allergy prevalence in high-risk infants. However, questions remain as to how to identify and target the "at-risk" population to facilitate timely introduction of peanut., Objective: We sought to use population-based infant peanut allergy data to understand feasibility and implications of implementing the LEAP trial intervention., Methods: Using the HealthNuts study cohort (n = 5276) of 1-year-old infants, we explored the impact of using various criteria to identify infants at high risk of developing peanut allergy, and the implications of skin prick test (SPT) screening before peanut introduction., Results: Screening all infants with early onset eczema and/or egg allergy could require testing 16% of the population and would still miss 23% of peanut allergy cases; 29% of screened infants would require clinical follow-up because of being SPT-positive. Around 11% of high-risk infants were excluded from the LEAP study because of an SPT wheal size of more than 4 mm to peanut at baseline; data from the HealthNuts study suggest that 80% of these would be peanut allergic on food challenge. There were no life-threatening events among either low- or high-risk infants whose parents chose to introduce peanut at home in the first year of life, or in 150 peanut-allergic infants during hospital-based challenges., Conclusions: Based on this large epidemiological study, a population program aiming to identify and screen all infants at risk of peanut allergy would pose major cost and logistic challenges that need to be carefully considered. Further research might be required to provide data for low-risk infants., (Copyright © 2016. Published by Elsevier Inc.)

Background: The diagnosis of food allergy (FA) can be challenging because approximately half of food-sensitized patients are asymptomatic. Current diagnostic tests are excellent makers of sensitization but poor predictors of clinical reactivity. Thus oral food challenges (OFCs) are required to determine a patient's risk of reactivity., Objective: We sought to discover genomic biomarkers of clinical FA with utility for predicting food challenge outcomes., Methods: Genome-wide DNA methylation (DNAm) profiling was performed on blood mononuclear cells from volunteers who had undergone objective OFCs, concurrent skin prick tests, and specific IgE tests. Fifty-eight food-sensitized patients (aged 11-15 months) were assessed, half of whom were clinically reactive. Thirteen nonallergic control subjects were also assessed. Reproducibility was assessed in an additional 48 samples by using methylation data from an independent population of patients with clinical FA., Results: Using a supervised learning approach, we discovered a DNAm signature of 96 CpG sites that predict clinical outcomes. Diagnostic scores were derived from these 96 methylation sites, and cutoffs were determined in a sensitivity analysis. Methylation biomarkers outperformed allergen-specific IgE and skin prick tests for predicting OFC outcomes. FA status was correctly predicted in the replication cohort with an accuracy of 79.2%., Conclusion: DNAm biomarkers with clinical utility for predicting food challenge outcomes are readily detectable in blood. The development of this technology in detailed follow-up studies will yield highly innovative diagnostic assays., (Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: The evidence on whether the atopic march observed in childhood (ie, the progression from eczema to allergic rhinitis and asthma) extends to adulthood is sparse, and there is no evidence on whether the progression leads to a specific phenotype of asthma., Objective: We sought to assess whether childhood eczema and rhinitis are risk factors for specific phenotypes of adult asthma., Methods: Participants of the Tasmanian Longitudinal Health Study recruited in 1968 (age range, 6.0-7.0 years) were followed up at age 44 years. The risk of current atopic or nonatopic asthma in middle age characterized by sensitization to aeroallergens given childhood eczema, rhinitis, or both was calculated by using multinomial logistic regression., Results: No association was found between childhood eczema or rhinitis and nonatopic adult asthma. In contrast, childhood eczema and rhinitis in combination predicted both new-onset atopic asthma by middle age (adjusted multinomial odds ratio [aMOR], 6.3; 95% CI, 1.7-23.2) and the persistence of childhood asthma to adult atopic asthma (aMOR, 11.7; 95% CI, 3.6-37.9). Participants with childhood eczema alone were at increased risk of new-onset atopic asthma (aMOR, 4.1; 95% CI, 1.9-8.8), whereas rhinitis alone predicted the persistence of childhood asthma to atopic asthma (aMOR, 2.7; 95% CI, 1.3-5.6). Of all asthma, 29.7% of persistent atopic asthma and 18.1% of new-onset atopic asthma could be attributed to having childhood eczema and rhinitis., Conclusion: Childhood eczema and rhinitis are strongly associated with the incidence and persistence of adult atopic asthma., (Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Background: A recent cohort study suggested that intake of soy milk or soy formula was associated with peanut allergy. If this finding is confirmed, it suggests an avenue for modification of diet as a peanut allergy prevention strategy., Objective: To investigate the relationship between soy consumption and peanut sensitization in a prospective cohort study of children., Methods: A total of 620 babies with a family history of allergic disease were recruited. Dietary information was obtained from telephone interviews every 4 weeks from birth until 15 months and then again at 18 months and 2 years. Skin prick tests to peanut, milk, and egg were performed at 6, 12, and 24 months. A wheal size > or = 3 mm was considered positive for sensitization., Results: Children whose parents elected to introduce soy formula or soy milk into their children's diet were more likely to be sensitized to peanuts at 2 years (odds ratio, 2.02; 95% CI, 1.04-3.92; P = .039). However, this relationship was explained by feeding of soy to children who had siblings with milk allergy or were themselves sensitized to milk. After adjusting for these factors, there was no evidence of an association between soy consumption and peanut sensitization (odds ratio, 1.34; 95% CI, 0.64-2.79; P = .434)., Conclusion: The association between soy consumption and peanut sensitization is not causal but merely a result of preferential use of soy milk in infants with a personal or family history of cow's milk allergy. Future studies should take the confounding effects related to dietary modifications by parents into account when investigating the association between diet and childhood allergic diseases.