ABSTRACT
PURPOSE OF REVIEW: The goal of this review is to present an updated summary of the various approaches to prevent childhood food allergies and report recent advances in potential prevention trials for food allergy. RECENT FINDINGS: Several approaches related to maternal dietary supplementation as well as infant GI-based supplementation have been tried and are the subject of ongoing clinical investigation. The prevalence of food allergy appears to be increasing but several, varied approaches to prevention are being actively pursued such that an effective strategy may not be too far in the future.
Subject(s)
Food Hypersensitivity/prevention & control , Primary Prevention/methods , Child , Female , Humans , Infant , PregnancyABSTRACT
Epigenetic mechanisms integrate both genetic variability and environmental exposures. However, comprehensive epigenome-wide analysis has not been performed across major childhood allergic phenotypes. We examined the association of epigenome-wide DNA methylation in mid-childhood peripheral blood (Illumina HumanMethyl450K) with mid-childhood atopic sensitization, environmental/inhalant and food allergen sensitization in 739 children in two birth cohorts (Project Viva-Boston, and the Generation R Study-Rotterdam). We performed covariate-adjusted epigenome-wide association meta-analysis and employed pathway and regional analyses of results. Seven-hundred and five methylation sites (505 genes) were significantly cross-sectionally associated with mid-childhood atopic sensitization, 1411 (905 genes) for environmental and 45 (36 genes) for food allergen sensitization (FDR<0.05). We observed differential methylation across multiple genes for all three phenotypes, including genes implicated previously in innate immunity (DICER1), eosinophilic esophagitis and sinusitis (SIGLEC8), the atopic march (AP5B1) and asthma (EPX, IL4, IL5RA, PRG2, SIGLEC8, CLU). In addition, most of the associated methylation marks for all three phenotypes occur in putative transcription factor binding motifs. Pathway analysis identified multiple methylation sites associated with atopic sensitization and environmental allergen sensitization located in/near genes involved in asthma, mTOR signaling, and inositol phosphate metabolism. We identified multiple differentially methylated regions associated with atopic sensitization (8 regions) and environmental allergen sensitization (26 regions). A number of nominally significant methylation sites in the cord blood analysis were epigenome-wide significant in the mid-childhood analysis, and we observed significant methylation - time interactions among a subset of sites examined. Our findings provide insights into epigenetic regulatory pathways as markers of childhood allergic sensitization.
Subject(s)
Biomarkers/analysis , DNA Methylation , Environmental Illness/epidemiology , Epigenome , Food Hypersensitivity/epidemiology , Hypersensitivity, Immediate/epidemiology , Adult , Child , CpG Islands , Cross-Sectional Studies , Environmental Illness/diagnosis , Environmental Illness/genetics , Environmental Illness/immunology , Female , Fetal Blood/chemistry , Follow-Up Studies , Food Hypersensitivity/diagnosis , Food Hypersensitivity/genetics , Food Hypersensitivity/immunology , Genome-Wide Association Study , Gestational Age , Humans , Hypersensitivity, Immediate/diagnosis , Hypersensitivity, Immediate/genetics , Hypersensitivity, Immediate/immunology , Incidence , Longitudinal Studies , Male , Phenotype , Prognosis , United States/epidemiologyABSTRACT
BACKGROUND: Many parents of food allergic children have concerns about the development of food allergies in their other children. OBJECTIVE: We sought to determine prevalence of food sensitization and clinical food allergy among siblings of food allergic children. METHODS: Two thousand eight hundred and thirty-four children were enrolled in the Chicago Family Cohort Food Allergy study. One thousand one hundred and twenty children (ages 0-21 years) with a food allergy (defined by a reported reaction history and evidence of food-specific IgE or skin prick test) and at least 1 biological sibling were included in this study. RESULTS: Among siblings of children with food allergy, 33.4% had no sensitization and no clinical symptoms to food. Fifty-three percent had a positive food serum-specific IgE or skin prick test, but no reported symptoms of food allergy. Only 13.6% of siblings were both sensitized and clinically reactive to the same food. Milk allergy was the most common allergy among siblings (5.9%), followed by egg allergy (4.4%) and peanut allergy (3.7%). CONCLUSIONS: In a large cohort of food allergic families, only a small proportion of siblings were both sensitized and clinically reactive to a food. Sensitization without reactivity was common among siblings. Testing for food allergy in siblings without a history of clinical reactivity appears to be unjustified. Screening may lead to negative consequences related to potential misdiagnosis and unnecessary avoidance of a food. More data are needed to determine the absolute risk of food allergy development in siblings of food allergic children.
Subject(s)
Food Hypersensitivity/epidemiology , Siblings , Adolescent , Adult , Allergens/immunology , Child , Child, Preschool , Female , Food/adverse effects , Food Hypersensitivity/blood , Food Hypersensitivity/diagnosis , Humans , Infant , Infant, Newborn , Male , Skin Tests , Young AdultABSTRACT
Pediatric food allergy is a growing health problem in the United States that has been found to adversely impact the quality of life of both affected children and their caregivers. This article provides a review of how food allergy affects the quality of life of patients and their families within the domains of school, social activities, relationships, and daily life. Efforts to improve food allergy-related quality of life among caregivers are also discussed.