Background Sensitization to individual cat and dog allergen molecules can contribute differently to development of allergy to these animals. Objective We sought to investigate the association between ...sensitization patterns to cat and dog allergen molecules during childhood and symptoms to these furry animals up to age 16 years. Methods Data from 779 randomly collected children from the Barn/Children Allergy/Asthma Milieu Stockholm Epidemiologic birth cohort at 4, 8, and 16 years were used. IgE levels to cat and dog were determined by using ImmunoCAP, and levels to allergen molecules were determined by using an allergen chip based on ISAC technology (Mechanisms for the Development of Allergy chip). Allergy was defined as reported rhinitis, conjunctivitis, or asthma at exposure to cat or dog. Results Cross-sectionally, IgE to Fel d 1 and cat extract had similar positive predictive values for cat allergy. IgE to Can f 1 showed a higher positive predictive value for dog allergy than dog extract IgE. Sensitizations to Fel d 1 and Can f 1 in childhood were significantly associated with symptoms to cat or dog at age 16 years. Polysensitization to 3 or more allergen molecules from cat or dog was a better longitudinal predictor of cat or dog symptoms than results of IgE tests with cat or dog allergen extract, respectively. Cross-sectionally, cat/dog-polysensitized children had higher IgE levels and more frequent symptoms to cat and dog than monosensitized children. Conclusions Sensitization to Fel d 1 and Can f 1 in childhood and polysensitization to either cat or dog allergen molecules predict cat and dog allergy cross-sectionally and longitudinally significantly better than IgE to cat or dog extract.
Background Isolated Ara h 8 sensitization is suggested to be associated with no or mild symptoms among peanut-sensitized subjects. Objective We sought to investigate the occurrence of systemic ...reactions in children with isolated sensitization to Ara h 8. Methods Participants were 144 children sensitized to Ara h 8 (≥0.35 kUA /L) but not to Ara h 1, Ara h 2, or Ara h 3 (<0.35 kUA /L). An open oral challenge with peanut was performed in those subjects who did not consume peanut regularly, and an extended IgE reactivity profile was obtained. If the child had a documented history of systemic reactions up to grade I anaphylaxis, double-blind, placebo-controlled food challenges were performed. Results One hundred twenty-nine (89.5%) children were either peanut consumers or did not react to peanut challenge. Another 14 (9.7%) children experienced oral cavity symptoms at the first 2 but not subsequent challenge doses. At the time of the double-blind, placebo-controlled food challenge, 1 boy with a previous mild systemic reaction to peanut experienced lip swelling, stomach cramping, and objective tiredness. Reanalysis of IgE levels showed an increase in peanut IgE levels from 1.5 to 8.8 kUA /L, but IgE levels to Ara h 8 remained stable and IgE levels to Ara h 1, Ara h 2, and Ara h 3 were all still less than 0.35 kUA /L. The IgE level to Ara h 6 was 0.45 kUA /L. Conclusion Isolated Ara h 8 sensitization indicates tolerance to peanuts in almost all cases. However, sensitization against thus far unidentified determinants in peanut might cause symptoms in rare cases.
Background Not much data are available from large, unselected, birth cohort studies on the natural course and comorbidities of rhinitis in children. Objective To study phenotypes of rhinitis in ...relation to the natural course and comorbidities of allergic diseases in preschool-age and early school-age children. Methods We analyzed data from a birth cohort of 2024 children, for whom information on IgEs against 8 common inhaled allergens was available, collected at age 4 and 8 years. The children were assigned to groups of allergic rhinitis (rhinitis with sensitization to allergens), nonallergic rhinitis (rhinitis without sensitization), allergic sensitization but no rhinitis, or neither rhinitis nor sensitization. Results The proportion of children with allergic rhinitis increased from 5% to 14% from age 4 to 8 years, whereas the proportion of children with nonallergic rhinitis decreased slightly over the same period of development, from 8% to 6%. Of the children with allergic rhinitis when they were 4 years old, 12% underwent remission by the time they were 8 years old; of the children with nonallergic rhinitis, 73% underwent remission during this period of development. Among 4-year-olds without rhinitis who were sensitized to allergen, 56% had allergic rhinitis when they were 8 years old. Among 4- and 8-year-olds, allergic rhinitis and nonallergic rhinitis were associated with asthma, eczema, and food hypersensitivity. Twenty-five percent of 8-year-olds with allergic rhinitis also had oral allergy syndrome. Conclusions Fewer preschool-age children with allergic rhinitis undergo remission than do those with nonallergic rhinitis. Sensitization to inhaled allergens at an early age (4 years) precedes the development of allergic rhinitis, whereas symptoms of rhinitis do not. Oral allergy syndrome is common among 8-year-olds with allergic rhinitis.
IgE signatures to peanut allergen measured in early childhood allow predicting the likelihood of peanut allergy in adolescence. Peanut symptoms and Ara h 2 IgE >2.0 ISU-E at 4 years predict peanut ...allergy in adolescence.
Asthma, rhinitis, and eczema are complex diseases with multiple genetic and environmental factors interlinked through IgE-associated and non–IgE-associated mechanisms. Mechanisms of the Development ...of ALLergy (MeDALL; EU FP7-CP-IP; project no: 261357; 2010-2015) studied the complex links of allergic diseases at the clinical and mechanistic levels by linking epidemiologic, clinical, and mechanistic research, including in vivo and in vitro models. MeDALL integrated 14 European birth cohorts, including 44,010 participants and 160 cohort follow-ups between pregnancy and age 20 years. Thirteen thousand children were prospectively followed after puberty by using a newly standardized MeDALL Core Questionnaire. A microarray developed for allergen molecules with increased IgE sensitivity was obtained for 3,292 children. Estimates of air pollution exposure from previous studies were available for 10,000 children. Omics data included those from historical genome-wide association studies (23,000 children) and DNA methylation (2,173), targeted multiplex biomarker (1,427), and transcriptomic (723) studies. Using classical epidemiology and machine-learning methods in 16,147 children aged 4 years and 11,080 children aged 8 years, MeDALL showed the multimorbidity of eczema, rhinitis, and asthma and estimated that only 38% of multimorbidity was attributable to IgE sensitization. MeDALL has proposed a new vision of multimorbidity independent of IgE sensitization, and has shown that monosensitization and polysensitization represent 2 distinct phenotypes. The translational component of MeDALL is shown by the identification of a novel allergic phenotype characterized by polysensitization and multimorbidity, which is associated with the frequency, persistence, and severity of allergic symptoms. The results of MeDALL will help integrate personalized, predictive, preventative, and participatory approaches in allergic diseases.
To the Editor: It has been shown that IgE antibodies to common allergens start with the development of such antibodies to foods followed by IgE antibodies to airborne allergens.1,2 Cross-reactive IgE ...is common to pollens and some pathogenesis-related proteins in fruits, vegetables, legumes, and grains.3,4 Because information on the development and co-occurrence of allergen-specific IgE antibodies from early childhood up to adolescence is limited in large population samples, we sought to evaluate the development, progression, and transition of IgE antibodies to common airborne and food allergens. Definitions of exposures (parental allergy, breast-feeding, and second-hand tobacco smoke) and outcomes such as asthma, rhinitis, and eczema at 4 to 16 years are provided in this article's Online Repository and Table E1 at www.jacionline.org.6 At each follow-up, sera were first analyzed with Phadiatop and fx5, mixes with 14 airborne and food allergens, respectively.
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