Neutrophilic Steroid-Refractory Recurrent Wheeze and Eosinophilic Steroid-Refractory Asthma in Children.

Background: Little is known about inflammatory pathways of severe recurrent wheeze in preschool children and severe asthma in children.

Objectives: The aim of the Severe Asthma Molecular Phenotype cohort was to characterize phenotypes of severe recurrent wheeze and severe asthma during childhood in terms of triggers (allergic or not), involved cells (eosinophil or neutrophil), and corticoid responsiveness.

Methods: Children with moderate-to-severe asthma and preschool children with moderate-to-severe recurrent wheeze were enrolled prospectively.

What lessons can be learned about asthma phenotypes in children from cohort studies?

'Phenotyping' asthma by multivariate analyses and more recently by unsupervised analysis has been performed in children cohorts. We describe the key findings that have emerged from these cohorts. It would appear that there are three wheeze phenotypes in children of preschool age: the mild episodic viral wheeze phenotype; the multitrigger atopic wheeze; and, less often encountered, the severe non-atopic wheeze.

Casein-specific IL-4- and IL-13-secreting T cells: a tool to implement diagnosis of cow's milk allergy.

Background: Cow's milk allergy (CMA) is a frequent food allergy in young children. The oral food challenge is the gold standard for diagnosis, and there is currently no reliable biological test. Our aim was to evaluate the diagnostic potential of a functional assay quantifying allergen-specific Th2 cells in CMA children.

Quantification of circulating house dust mite-specific IL-4- and IL-13-secreting T cells correlates with rhinitis severity in asthmatic children and varies with the seasons.

Background: Defining suitable markers to diagnose and monitor allergy and its severity is essential to correctly assign patients for specific immunotherapy. Circulating levels of specific IgE are good markers of sensitization, but not of clinically symptomatic allergy.

Objective: To quantify circulating interleukin (IL)-4- and IL-13-secreting T cells specific for house dust mite (HDM) in children presenting HDM-allergic asthma associated or not with rhinitis and correlate results with clinical symptoms.

Childhood allergic asthma is not a single phenotype.

Objective: IgE-mediated allergic asthma phenotype appears to be heterogeneous. We set out to define distinct allergic phenotypes by unsupervised cluster analysis.

Study Design: A total of 18 variables were analyzed: sex and age, eczema and food allergy, asthma duration, asthma severity and control, severe exacerbations, total IgE level, allergic sensitization, fractional exhaled nitric oxide, and functional parameters.

Wheeze phenotypes in young children have different courses during the preschool period.

Background: Rules for predicting the course of asthma in wheezy infants have low specificity.

Objective: To determine if the novel phenotypes-mild early viral wheeze (EVW), atopic multiple-trigger wheeze (MTW), and nonatopic uncontrolled wheeze (NAUW)-have different courses during the preschool period.

Methods: Part of the prospectively followed Trousseau Asthma Program cohort was phenotyped using cluster analysis with 12 parameters (sex, asthma severity and control with inhaled corticosteroid [ICS], parental asthma, allergic rhinitis, eczema, food allergy, EVW or MTW, and allergen exposure trigger).

Novel severe wheezy young children phenotypes: boys atopic multiple-trigger and girls nonatopic uncontrolled wheeze.

Background: Recurrent wheezing during infancy is a heterogeneous disorder that has been associated with early-onset asthma.

Objective: To identify phenotypes of severe recurrent wheezing and therapeutic approaches.

Methods: We performed cluster analysis with 20 variables of 551 children with active asthma, younger than 36 months old, and enrolled in the Trousseau Asthma Program.

Two novel, severe asthma phenotypes identified during childhood using a clustering approach.

Unsupervised cluster analysis has already been used to identify severe phenotypes of childhood asthma, but without taking into account inflammatory markers. The aim of this study was to define independent homogeneous phenotypic clusters of severe asthma in a cohort of asthmatic children. Cluster analysis was applied to 19 variables from 315 children enrolled in the Trousseau Asthma Program in Paris, France.