Airway inflammatory biomarkers in different asthma phenotypes

Background Asthma is a diverse disease with various phenotypes. Correlation of clinical asthma phenotypes with their underlying inflammatory biomarkers could help tailor asthma management and in turn improve the patient’s outcome. Aim of the study To validate the clinical classification of asthma phenotypes and to portray cough-predominant asthma phenotype and wheezy phenotype in accordance with their related inflammatory biomarkers. Patients and methods This is a case–control study comprising 50 patients with cough-predominant asthma phenotype and 50 patients with wheezy asthma phenotype, together with 50 healthy controls. Serum interleukin-10 (IL-10), transforming growth factor-beta 1 (TGF-β1), and total serum immunoglobulin E (IgE) levels were assessed using immunoassay techniques. Results The asthmatic children showed a significant increase of eosinophilic percentage, total serum IgE, and TGF-β1, when compared with the control group, whereas they showed a significant decrease of serum IL-10 when compared with the control group. As regards the clinical characteristics of both phenotypes, the prevalence of associated allergic rhinitis and atopic dermatitis in patients with cough-predominant asthma was significantly higher compared with the wheezy group. As regards laboratory biomarkers, total serum IgE was significantly elevated in cough-predominant asthma phenotype compared to wheezy phenotype. No significant differences were found between both phenotypes regarding serum TGF-β1 and IL-10. Conclusion Cough-predominant asthma phenotype is characterized by prominent atopic features (allergic manifestations and elevated total IgE). However, cough-predominant asthma and wheezy asthma phenotypes were similar regarding serum TGF-β1 and IL-10.