This Synopsis Book reports advances and key observations that will affect the care of children with allergic and immunologic diseases now and in the near future. Reviewers selected* many articles that provide clinical “pearls” and insights that are applicable to daily practice, as well as ones that challenge our previous notions and provide data that may lead to new approaches for diagnosis and treatment.
Several studies provide results supporting the “hygiene hypothesis.” The association between maternal use or early use of antibiotics in children and risk for developing allergic disorders is explored by a few groups, and their findings provide further support that perturbations in microbial exposure in early life can influence one’s risk. Additional studies explore the influence of early life environmental exposures, including air pollution and tobacco smoke, on the development of allergic disorders.
Of note, several studies acknowledge and discuss the possibility of bias that can influence these findings. In particular, a nationwide population study from Sweden highlights the potential for several types of bias, including reverse causation and confounding by indication, that need to be considered. Nevertheless, by identifying relevant, modifiable risk factors, effective strategies to prevent allergies may be developed.
Our reviewers selected a large number of studies related to food allergies. A noteworthy study (LEAP) from the United Kingdom reported that early introduction of peanut dramatically decreases the risk of developing a peanut allergy in high-risk infants. These compelling results have led to the review of current food allergy guidelines, and it is anticipated that guideline revisions will be forthcoming to clarify how best to apply these results in clinical practice.
Additional research reinforces the knowledge that not all routes of allergen exposure are equal. Whereas early oral exposure promotes tolerance, environmental exposure to peanut allergen through inflamed eczematous skin is found to be a risk factor for sensitization. Other studies reviewed also support the increased risk of food allergen sensitization in children with eczema.
As seen in a number of studies on food allergy, improved diagnostic ability to distinguish between sensitization and allergy remains an important goal as the gold standard oral food challenge continues to be a time- and resource-intensive procedure that carries the risk of significant reactions. However, 1 study reminds us of the potential negative impact of overreliance on test results alone, specifically the overdiagnosis of food allergies when panel testing is used. This can result in unnecessary nutritional, social, and economic burdens. As 2 studies highlight, growth impairment and decreased bone mineral density are real risks for children on milk avoidance diets, emphasizing the importance of accurate food allergy diagnoses and dietary counseling to ensure optimal nutritional intake for these children.
A substantial number of articles pertaining to asthma were selected this year by our reviewers. Several studies draw attention to the effects of early airway inflammation on adult lung function, supporting the need for early diagnosis and intervention. The utility of measuring biomarkers in exhaled breath condensate in infants and young children, such as nitric oxide and volatile organic compounds, has been explored in hope of enhancing our ability to distinguish between children who are transient wheezers from children who will continue to have asthma symptoms as they get older. Additional studies examined “best practices” for asthma management and use of technology to educate and improve adherence to medications. These findings may serve to improve outcomes in children currently diagnosed with asthma.
Studies reviewed on primary immunodeficiency highlight the success of the newborn screening program in identifying infants with SCID and other severe T-cell immunodeficiencies, allowing for early intervention. By giving these infants the opportunity of initiating definitive therapy with hematopoietic stem cell transplantation soon after diagnosis, they have a high likelihood for successful immune reconstitution.
On behalf our reviewers, we hope that this supplement stimulates and informs, giving you practical information to improve the care of children with allergic and immunologic diseases now and an exciting peek out the window toward understanding therapies on the horizon. For additional information about our Section, please visit: http://www.aap.org/sections/allergy.
- Copyright © 2015 by the American Academy of Pediatrics