Persistent ventilation inhomogeneity after an acute exacerbation in preschool children with recurrent wheezing

Abstract

Background Preschool children with recurrent wheezing suffer high morbidity. It is unclear whether objective measures of asthma control, such as pulmonary function tests (PFTs), provide additional information to the clinical assessment. Methods We recruited children between 3 and 6 years old, with a history of recurrent wheezing in the preceding year and treated for acute wheezing exacerbation in the emergency department (ED) into an observational cohort study. Children attended two outpatient visits: the first study visit within five days of discharge from the ED and the second study visit 12 weeks after the ED visit. We performed standardized symptom score (test for respiratory and asthma control in kids (TRACK)), multiple breath washout (MBW), spirometry, and clinical assessment at both visits. Results Seventy‐four children, mean (standard deviation (SD)) age of 4.32 years (0.84), attended both visits. Paired FEV0.75 and lung clearance index (LCI) measurements at both time points were obtained in 37 and 34 subjects, respectively. Feasibility for all tests improved at visit 2 and was not age‐dependent. At the second study visit, a third had controlled asthma based on the TRACK score, and the mean lung clearance index (LCI) improved from 9.86 to 8.31 (P = .003); however, 46% had an LCI in the abnormal range. FEV0.75 z‐score improved from −1.66 to −1.17 (P = .05) but remained in the abnormal range in 24%. LCI was abnormal in more than half of the children with “well‐controlled” asthma based on the TRACK score. There was no correlation between PFT measures and TRACK scores at either visit. Conclusions Lung clearance index demonstrates a persistent deficit post‐exacerbation in a large proportion of preschoolers with recurrent wheezing, highlighting that symptom scores alone may not suffice for monitoring these children.

Multicentre feasibility of multiple-breath washout in preschool children with cystic fibrosis and other lung diseases

“…Besides the role of LCI in surveillance of lung disease and its use to investigate response to therapy in patients with CF, MBW gains increasing attention for monitoring of lung function in other childhood lung disease such as asthma or PCD [29,30]. In this context, the high success rate of MBW measurements in preschool children with other lung diseases (figure 1) and detection of substantially elevated LCI values in the two children with PCD participating in our study is encouraging and provides initial support of LCI as promising noninvasive quantitative outcome measure in other early-onset lung diseases in children ( figure 3).…”

Modeling the conversion between specific IgE test platforms for nut allergens in children and adolescents

“…This study was approved by the ethics board of the Hospital for Sick Children (REB #:1000053791) and the Medical University of Vienna (EK Nr 2302/2016). Additionally, 42 children with sensitizations were selected from the Wheezy ER study on pre‐school asthma between 3 and 6 years of age (REB #:1000041089), based on inclusion criteria reported previously 16,17 . These children presented to the Emergency Department at the Hospital for Sick Children with an acute wheezing exacerbation, a history of at least two wheezing episodes during the last 12 months, and displayed sensitization to food and/or inhalant allergens 18 …”

Pulmonary functional MRI: Detecting the structure–function pathologies that drive asthma symptoms and quality of life

“…PfMRI VDP correlates strongly with LCI measurements in adult 8 and paediatric 40 patients with asthma. Given that an elevated (abnormal) LCI is thought to reflect ventilation heterogeneity caused by small airways abnormalities, even in those with normal spirometry, 39,41 PfMRI can be thought of as more sensitive to small airway dysfunction as compared to spirometry and MBW.…”