International consensus on (ICON) pediatric asthma

Asthma is the most common chronic lower respiratory disease in childhood throughout the world. Several guidelines and/or consensus documents are available to support medical decisions on pediatric asthma. Although there is no doubt that the use of common systematic approaches for management can considerably improve outcomes, dissemination and implementation of these are still major challenges. Consequently, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), recently formed by the EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus on (ICON) Pediatric Asthma. The purpose of this document is to highlight the key messages that are common to many of the existing guidelines, while critically reviewing and commenting on any differences, thus providing a concise reference. The principles of pediatric asthma management are generally accepted. Overall, the treatment goal is disease control. To achieve this, patients and their parents should be educated to optimally manage the disease, in collaboration with healthcare professionals. Identification and avoidance of triggers is also of significant importance. Assessment and monitoring should be performed regularly to re-evaluate and fine-tune treatment. Pharmacotherapy is the cornerstone of treatment. The optimal use of medication can, in most cases, help patients control symptoms and reduce the risk for future morbidity. The management of exacerbations is a major consideration, independent of chronic treatment. There is a trend toward considering phenotype-specific treatment choices; however, this goal has not yet been achieved.

Gene-vitamin D interactions on food sensitization: a prospective birth cohort study

BACKGROUND

It has been hypothesized that vitamin D deficiency (VDD) contributes to the development of food sensitization (FS) and then food allergy. However, the epidemiological evidence is conflicting. We aim to examine whether cord blood VDD is associated with FS and whether such association can be modified by genetic variants in a prospective birth cohort.

METHODS

This study included 649 children who were enrolled at birth and followed from birth onward at the Boston Medical Center. We defined VDD as cord blood 25(OH)D < 11 ng/ml, and FS as specific IgE ≥ 0.35 kUA/l to any of eight common food allergens in early childhood. We genotyped potentially functional single-nucleotide polymorphisms (SNPs) in 11 genes known to be involved in regulating IgE and 25(OH)D concentrations. Logistic regressions were used to test the effects of VDD on FS individually and jointly with SNPs.

RESULTS

Among the 649 children, 44% had VDD and 37% had FS. When examined alone, VDD was not associated with FS. When examined jointly with SNPs, a significant interaction between IL4 gene polymorphism (rs2243250) and VDD (p(interaction) = 0.003, p(FDR) = 0.10) was found: VDD increased the risk of FS among children carrying CC/CT genotypes (OR = 1.79, 95%CI: 1.15-2.77). Similar but weaker interactions were observed for SNPs in MS4A2 (rs512555), FCER1G (rs2070901), and CYP24A1 (rs2762934). When all four SNPs were simultaneously considered, a strong gene-VDD interaction was evident (p(interaction) = 9 × 10(-6) ).

CONCLUSIONS

Our data demonstrate that VDD may increase the risk of FS among individuals with certain genotypes, providing evidence of gene-vitamin D interaction on FS.

Familial aggregation of food allergy and sensitization to food allergens: a family-based study

BACKGROUND

The increasing prevalence of food allergy (FA) is a growing clinical and public health problem. The contribution of genetic factors to FA remains largely unknown.

OBJECTIVE

This study examined the pattern of familial aggregation and the degree to which genetic factors contribute to FA and sensitization to food allergens.

METHODS

This study included 581 nuclear families (2,004 subjects) as part of an ongoing FA study in Chicago, IL, USA. FA was defined by a set of criteria including timing, clinical symptoms obtained via standardized questionnaire interview and corroborative specific IgE cut-offs for > or =95% positive predictive value (PPV) for food allergens measured by Phadia ImmunoCAP. Familial aggregation of FA as well as sensitization to food allergens was examined using generalized estimating equation (GEE) models, with adjustment for important covariates including age, gender, ethnicity and birth order. Heritability was estimated for food-specific IgE measurements.

RESULTS

FA in the index child was a significant and independent predictor of FA in other siblings (OR=2.6, 95% CI: 1.2-5.6, P=0.01). There were significant and positive associations among family members (father-offspring, mother-offspring, index-other siblings) for total IgE and specific IgE to all the nine major food allergens tested in this sample (sesame, peanut, wheat, milk, egg white, soy, walnut, shrimp and cod fish). The estimated heritability of food-specific IgE ranged from 0.15 to 0.35 and was statistically significant for all the nine tested food allergens.

CONCLUSION

This family-based study demonstrates strong familial aggregation of FA and sensitization to food allergens, especially, among siblings. The heritability estimates indicate that food-specific IgE is likely influenced by both genetic and environmental factors. Together, this study provides strong evidence that both host genetic susceptibility and environmental factors determine the complex trait of IgE-mediated FA.

Allergy evaluation and immunotherapy

Up to 10% of children and adolescents in the United States may have asthma and up to 40% may be affected by allergic rhinitis. Most people know that asthma is a serious disease, but "hay fever" is often mistakenly considered trivial. However, hay fever symptoms can significantly influence a patient's quality of life, causing fatigue, headache, and even cognitive impairment. Both asthma and allergic rhinitis can result in lost sleep, many missed school days, and the inability to participate in sports and other recreational activities in which young people engage. An appropriate diagnosis is the first step toward improving quality of life for these young patients. This article reviews diagnostic procedures for allergic disease, and-because compliance is frequently an issue with school-aged patients-it also reviews current thinking on allergen immunotherapy, a treatment that provides effective long-term control in appropriately selected patients.

A follow-up study in a lead smelter community following the introduction of an effective pollution control system

A follow-up study using biological and environmental monitoring was performed in a lead smelter community to assess the health risk of inhabitants and to establish how long it takes after the introduction of an effective emission control system to declare a lead-contaminated area safe for normal living. In specific population groups (mothers and children) biological indicators of lead exposure and lead effect on hemoglobin synthesis were determined 2 years before and 11 consecutive years after the installation of bag filters. At the same time lead was monitored in the airborne and deposited particulates, in household dust and in soil. The results clearly show that the process of normalization is rather slow. The difference in blood lead and erythrocyte delta-aminolevulinic acid dehydratase between the exposed and control groups, even 12 years after bag filters installation, was still remarkable. It appears that soil, contaminated with lead from past exposure, is a major source of increased lead absorption in a population for many years.