Background: It is unclear whether sensitization patterns differentiate children with severe recurrent wheeze (SRW) / severe asthma (SA) from those with non-severe recurrent wheeze (NSRW) / non-severe asthma (NSA). Our objective was to compare the sensitization patterns between children with SRW/SA and NSRW/NSA from the French COBRAPed cohort. Methods: IgE to 112 components (c-sIgE) (ImmunoCAP® ISAC) were analyzed in 125 preschool (3-6 years) and 170 school-age children (7-12 years). Supervised analyses and clustering methods were applied to identify patterns of sensitization among children with positive c-sIgE. Results: We observed c-sIgE sensitization in 51% of preschool and 75% of school-age children. Sensitization to house dust mite (HDM) components was more frequent among NSRW than SRW (53% vs 24%, p<0.01). Sensitization to non-specific lipid transfer protein (nsLTP) components was more frequent among SA than NSA (16% vs 4%, p<0.01) and associated with a FEV1/FVC <-1.64 z-score. Among sensitized children, seven clusters with varying patterns were identified. The two broader clusters identified in each age group were characterized by “few sensitizations, mainly to HDM”. One cluster (n=4) with “multiple sensitizations, mainly to grass pollen, HDM, PR-10, and nsLTP” was associated with SA in school-age children. Conclusions: Although children with wheeze/asthma display frequent occurrences and high levels of sensitization, the sensitization patterns did not clearly discriminate children with severe disease from those with milder disease. These results suggest that the severity of wheeze/asthma may depend on both IgE- and non-IgE-mediated mechanisms.

INTRODUCTION: Exacerbations in preschool wheezers increase the risk of impaired lung function and asthma persistence at school age. Bronchial remodelling-based latent classes identify severe preschool wheezers at increased risk of frequent exacerbations (>3) but failed to distinguish those without exacerbation from those with low exacerbations rate (1-2 exacerbations) in the year following bronchoscopy. We thus aimed to identify further independent factors associated with no, low or high exacerbation rates. METHODS: In this post-hoc analysis, 80 severe preschool wheezers from the “P’tit Asthme” and “RESPIRE” studies were divided into 3 groups: No-Ex (0 exacerbation in the year following the bronchoscopy, n=20), Low-Ex (1-2 exacerbations, n=27) and High-Ex (≥3 exacerbations, n=33). Associations between variables and groups were assessed using multinomial logistic regressions. RESULTS: Atopic dermatitis, age at the first wheezing episode, Haemophilus and Streptococcus genera in the bronchoalveolar lavage fluid (BALF), bronchial smooth muscle (BSM) area, reticular basement membrane (RBM) thickness and RBM-BSM distance were all significantly different between No-Ex and/or Low-Ex and/or High-Ex. However, only atopic dermatitis, age at first episode of wheezing, Haemophilus genus in the BALF, RBM-BSM distance and BSM area were significantly and independently associated with exacerbation frequency. Among them, the BSM area was the sole parameter independently associated with each group. CONCLUSION: While atopic dermatitis, age at the first episode of wheezing, Haemophilus in BALF, RBM-BSM distance and BSM area appeared to be relevant independent parameters associated with exacerbation susceptibility in severe preschool wheezers, only the increased BSM area discriminated between each of the three-exacerbation frequency-based groups.

Background: The ability to perceive bronchial obstruction is variable in asthma. This is one of the main causes of inaccurate asthma control assessment, on which therapeutic strategies are based. Objective: Primary: To evaluate the ability of a clinical and spirometric telemonitoring device to characterize symptom perception profile in asthmatic children. Secondary: To evaluate its impact on asthma management (control, treatment, respiratory function variability) and the acceptability of this telemonitoring system. Method: 26 asthmatic children aged 6-18 years equipped with a portable spirometer and a smartphone application were monitored remotely for 3 months. Clinical and spirometric data were automatically transmitted to a secure internet platform. A medical team contacted the patient to optimize management. Three physicians blindly and independently classified the patients according to their perception profile. The impact of telemonitoring on the quantitative data was assessed at the beginning (T0) and end (T3 months) of telemonitoring, using matched statistical tests. Results: Patients could initially be classified according to their perception profile, with a concordance between the 3 observers of 64% (kappa coefficient: 0.55, 95%CI [0.39; 0.71]). After further discussion, a consensus was reached and resulted in 97% concordance (kappa coefficient: 0.97, 95%CI [0.91; 1.00]). There was a trend towards improvement in the ACT score, and a significant > 40% decrease in FEV1 and PEF variability, with good acceptance of the device. Conclusion: Clinical and spirometric telehome monitoring is applicable and can help define the perception profile of bronchial obstruction in asthmatic children. The device was generally well accepted.