Serum IgE as a Biomarker of Severity and Short-term Treatment Response in Steroid-naïve Children with Asthma: A Hospital-based Prospective Study

Introduction: Paediatric asthma is a growing public health challenge in Low- and Middle-Income Countries (LMICs), with increasing prevalence and substantial morbidity. Immunoglobulin E (IgE), a key mediator in type 2 airway inflammation, is often elevated in allergic asthma; however, its role as a severity biomarker and its responsiveness to treatment remain unclear in LMIC settings. Aim: To evaluate the role of serum IgE as a biomarker for baseline asthma severity and to assess its trends in relation to spirometric parameters following guideline-directed Inhaled Corticosteroid (ICS) therapy in steroid-naïve children with asthma. Materials and Methods: This hospital-based, prospective interventional study was conducted at the Department of Paediatrics, SRM Medical College Hospital and Research Centre, Chengalpattu, Tamil Nadu, India, over 14 months from October 2023 to December 2024. Children aged 5-14 years with newly diagnosed asthma were enrolled, excluding those on prior corticosteroid or anti-allergic therapy. Baseline and three-month post-treatment serum IgE levels were measured using Enzyme-linked Immunosorbent Assay (ELISA), and spirometry was performed following American Thoracic Society/European Respiratory Society (ATS/ERS) guidelines. ICSs were administered per Global Initiative for Asthma (GINA) 2023 recommendations. Correlation and Receiver Operating Characteristic (ROC) curve analysis were performed using Statistical Package for Social Sciences (SPSS) version 22.0. Results: Among 101 children, the mean age was 103.9±28.3 months, with a male predominance (64.4%). A stepwise increase in baseline IgE levels was observed with rising asthma severity. The ROC analysis demonstrated good diagnostic performance of serum IgE in identifying moderate to severe asthma, with an optimal cut-off of 362 IU/mL (sensitivity 80.4%, specificity 79.6%). Post-treatment IgE levels demonstrated a non-significant downward trend (p=0.1746) Although children with atopic dermatitis had higher mean serum IgE levels, the association was not statistically significant (p=0.6188), while spirometric improvement was consistent among all the children in the sample. Conclusion: Serum IgE correlates with baseline asthma severity and may serve as a low-cost, accessible biomarker for initial risk stratification in paediatric asthma Short-term ICS therapy did not result in a statistically significant change in serum IgE levels, indicating limited short-term biomarker responsiveness.