Phenotypes and endotypes of asthma in children

Asthma remains the most common chronic non-infectious respiratory disease in children, affecting about 14 – 15% of the global pediatric population. Current research shows that asthma is not a single disease, but a spectrum of different endotypes and phenotypes. Phenotypes describe the observed demographic and clinical characteristics of asthma, while endotypes reflect the underlying pathogenetic mechanisms of the disease. The aim. The review systematizes current data on clinical phenotypes (allergic and non-allergic asthma, preschool-age asthma, severe asthma) and inflammatory endotypes (T2-high and T2-low) of asthma in children. Results. Biomarkers used to identify endotypes and their clinical significance are analyzed. The main problems in determining phenotypes and endotypes of asthma in children are highlighted, including the possibility of combining several phenotypes in one patient, temporal instability of biomarkers, and the influence of comorbid conditions. Particular attention is paid to insufficient study of non-allergic asthma and T2-low endotype in children. Conclusion. It is shown that the determination of phenotypes and endotypes of asthma is critical for personalizing therapy and improving the prognosis of the disease. However, further studies of their stability over time and validation in prospective studies are needed for more effective use in clinical practice.

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