Evaluating Non-invasive Biomarkers to Diagnose Asthma in Children Aged 6 to Under 18 with Inconclusive Spirometry in Primary Care

What this Trial Is About

Researchers are investigating the use of accessible and non-invasive tests to improve asthma diagnosis in children aged 6 to under 18 years. Asthma is a common inflammatory disease affecting many children, but its diagnosis can be challenging due to limitations in current methods like spirometry and bronchial provocation testing, which is the gold standard but less accessible. This study aims to evaluate the usefulness of type 2 inflammation biomarkers, specifically fractional exhaled nitric oxide FeNO and blood eosinophil counts, to help diagnose asthma in children when spirometry results are inconclusive. Participants referred for bronchial provocation testing after inconclusive spirometry will have their FeNO measured using a specialized device and undergo blood tests for eosinophil counts and other markers. Additional tests include allergy testing, inflammatory protein analysis, nasosorption, and urine analysis. These procedures will take place before the methacholine challenge test. The study is observational and will include 123 children to assess the diagnostic accuracy of these biomarkers compared to the standard bronchial provocation test. During the study, participants will undergo medical assessments and complete standardized questionnaires about asthma control and quality of life. Researchers will analyze the diagnostic performance of FeNO and blood eosinophils and study their relationship with inflammatory proteins. Follow-up will include monitoring symptoms, medication use, and asthma exacerbations. The study also considers the impact of diagnostic delays on costs and environmental factors. Participation includes a baseline visit on the day of the methacholine challenge test, with no indication of long-term follow-up visits specified.

Diagnosing Asthma With Clinically Accessible, Non-invasive, and Efficient Tests: a Child-inclusive Translational Investigation