Reply: To PMID 25458910

Microbes and the Role of Antibiotic Treatment for Wheezy Lower Respiratory Tract Illnesses in Preschool Children

PURPOSE OF REVIEW

Antibiotics are commonly used to treat wheezy lower respiratory tract illnesses in preschoolers, although these infections have been traditionally thought to be predominantly of viral origin. Our purpose is to review recent research pertaining to the role of antibiotics in lower respiratory tract illnesses and on subsequent asthma development, as well as the possible mechanisms of their effects.

RECENT FINDINGS

Increasing evidence suggests that asthma pathogenesis is associated with events during infancy and early childhood, particularly respiratory tract infections. While viruses are frequently detected in children with lower respiratory tract infections, the presence of potentially pathogenic bacteria is also often detected and may play a role in asthma pathogenesis. Recent evidence suggests that use of macrolides, particularly azithromycin, may decrease the risk of and duration of lower respiratory tract illnesses and prevent future episodes in specific high-risk populations. Infants and preschoolers who have wheezy lower respiratory tract illnesses have a higher risk of asthma development. Alterations in the microbiome are thought to be influential. While several recent studies identify azithromycin as a therapeutic option in these illnesses, additional research is needed.

Advances in asthma 2015: Across the lifespan

In 2015, progress in understanding asthma ranged from insights to asthma inception, exacerbations, and severity to advancements that will improve disease management throughout the lifespan. 2015's insights to asthma inception included how the intestinal microbiome affects asthma expression with the identification of specific gastrointestinal bacterial taxa in early infancy associated with less asthma risk, possibly by promoting regulatory immune development at a critical early age. The relevance of epigenetic mechanisms in regulating asthma-related gene expression was strengthened. Predicting and preventing exacerbations throughout life might help to reduce progressive lung function decrease and disease severity in adulthood. Although allergy has long been linked to asthma exacerbations, a mechanism through which IgE impairs rhinovirus immunity and underlies asthma exacerbations was demonstrated and improved by anti-IgE therapy (omalizumab). Other key molecular pathways underlying asthma exacerbations, such as cadherin-related family member 3 (CDHR3) and orosomucoid like 3 (ORMDL3), were elucidated. New anti-IL-5 therapeutics, mepolizumab and reslizumab, were US Food and Drug Administration approved for the treatment of patients with severe eosinophilic asthma. In a clinical trial the novel therapeutic inhaled GATA3 mRNA-specific DNAzyme attenuated early- and late-phase allergic responses to inhaled allergen. These current findings are significant steps toward addressing unmet needs in asthma prevention, severity modification, disparities, and lifespan outcomes.