Reconstructing Phenotypes in Recurrent Severe Wheeze in Young Children
Year: 2021
Type: editorial
Abstract: Recurrent wheeze in preschool children is troublesome for patients and providers alike.Almost half of young children wheeze by age 6 years (1) and preschool children have the highest rate of emergency department visits for asthma symptoms (2).Clinicians are often challenged to make a diagnosis, choose therapy, and discuss prognosis with families amid great heterogeneity of recurrent wheeze.Several clinical categorizations, including episodic viral wheeze (EVW) and multitrigger wheeze (MTW) (3), that reflect some combination of pattern of wheeze and similarity to childhood asthma have been used to help clinical decision-making, but fall short of truly capturing the heterogeneity of the condition (4).Fortunately, most young children with recurrent wheeze improveover time (1)or respond well to available asthma therapies (5, 6).One of the fundamental limitations to advancing our understanding of preschool wheeze is the limited access to airway samples and functional assessments of underlying lung pathophysiology in the context of the symptoms and inflammatory phenotype.Children in this age group are frequently unable to produce high-quality pulmonary function tests, and there is a high threshold for subjecting a young child to the risk of anesthesia and bronchoscopy until many medical interventions have been exhausted.Research bronchoscopy in children is unethical.In this issue of the Journal, Robinson and colleagues (pp.523-535) aimed to identify the pathophysiologic underpinnings of severe respiratory disease in young children (7).They evaluated clinical symptoms, blood inflammatory markers, allergic sensitization, and BAL samples for cytology and microbes in 105 preschool children with recurrent severe wheeze (RSW) and 31 with nonwheeze respiratory disorders (NWRD) (i.e., recurrent croup, stridor, recurrent pneumonia) presenting for clinically indicated bronchoscopy.The authors examine the phenotypic and endotypic differences between the RSW and NWRD groups, then among the RSW group, based on the European Respiratory Society-endorsed wheezing phenotypes of EVW and MTW (3).Finally, an unbiased cluster analysis segregates a combination of eight clinicopathologic features and prescription of inhaled corticosteroid therapy to create four phenotypic clusters.Surprisingly, there were no differences between neutrophils, eosinophils, or presence of bacteria in BAL samples between the RSW and NWRD groups; only blood eosinophil count was higher in the RSW group.Similarly, among children with RSW, there were no differences in lower airway pathology identified between those
Author: Jonathan M. Gaffin
Institutions: Boston Children's Hospital, Harvard University
Language: English
Subfield: Physiology
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
OpenAlex ID: W3176578861