Clinical phenotypes in asthma during childhood

Area of Science:

• Pulmonology
• Allergy and Immunology
• Pediatric Respiratory Medicine

Background:

• Asthma is a complex respiratory disease with varied phenotypes based on onset, triggers, comorbidities, and inflammation.
• Early-onset asthma with multiple allergies and comorbidities is associated with persistent and severe disease in childhood.
• Phenotypic variation can occur over time due to evolving etiological triggers.

Purpose of the Study:

• To explore the heterogeneity of asthma phenotypes and their prognostic implications.
• To highlight the role of inflammatory cells and endotypes in asthma severity and prognosis.
• To discuss the potential link between severe asthma phenotypes and the development of chronic obstructive pulmonary disease (COPD).

Main Methods:

• Review of current understanding of asthma heterogeneity and phenotypes.
• Analysis of inflammatory pathways (eosinophilic and neutrophilic) and associated biomarkers.
• Discussion of prognostic factors, including age of onset, comorbidities, and specific inflammatory profiles.

Main Results:

• Asthma phenotypes are diverse, impacting disease severity and progression.
• Early-onset allergic asthma with multiple sensitizations predicts a poorer prognosis.
• Severe asthma is linked to distinct inflammatory endotypes: neutrophilic (often in younger children/teenagers, associated with obesity/microbiota) and eosinophilic (often in teenagers, linked to atopy).

Conclusions:

• Classifying asthma by endotypes and biomarkers is crucial for predicting prognosis and developing targeted therapies.
• Neutrophil and eosinophil-driven inflammation represent key endotypes in severe asthma.
• Severe asthma phenotypes may contribute to the development of adult COPD.