Diagnosing asthma in children using simple non-invasive tests

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

This study will test whether measuring exhaled nitric oxide (FeNO) and a blood eosinophil count can help diagnose asthma in children aged 6–17 when spirometry doesn't give a clear answer.

Quick facts

• Study type: Observational
• Enrollment: 123 (estimated)
• Ages: 6 Years to 17 Years
• Sex: All
• Sponsor: Université de Sherbrooke (Academic / other)
• Locations: 3 sites (Montreal, Quebec and 2 other locations)
• Trial ID: NCT07011394 on ClinicalTrials.gov

What this trial studies

This prospective observational study enrolls children 6 to <18 years who have asthma-like symptoms, inconclusive spirometry, and are referred from primary care for a methacholine bronchial provocation test. At participating pediatric centers, each child will have FeNO measured and a blood eosinophil count taken before undergoing the bronchial provocation test, which serves as the diagnostic reference. The investigators will calculate diagnostic performance metrics (sensitivity, specificity, predictive values) for FeNO and blood eosinophils alone and in combination and seek validated cut-offs applicable to primary care. The approach aims to determine whether these accessible, non-invasive biomarkers can reduce delays and misdiagnosis compared with current hospital-based diagnostic pathways.

Who should consider this trial

Good fit: Children aged 6 to <18 years with symptoms suggestive of asthma who have inconclusive spirometry and are referred for methacholine provocation by a non-specialist provider.

Not a fit: Children who recently used corticosteroids, have had a recent respiratory infection, are recent smokers, or have major cardiopulmonary disease are excluded and unlikely to benefit from the tests in this protocol.

Why it matters

Potential benefit: If successful, these simple tests could enable faster, less invasive asthma diagnosis in primary care, reducing delays to treatment and unnecessary specialist referrals.

How similar studies have performed: Previous studies in specialist clinics have shown that FeNO and blood eosinophils can aid asthma diagnosis and predict steroid response, but their usefulness in primary care and in younger children remains inadequately validated.

Eligibility criteria

Inclusion Criteria:

* Individuals aged 6 to \<18 years, presenting symptoms suggestive of asthma
* Patients referred for a methacholine bronchial provocation test by primary care (defined as non-pulmonologist, non-ENT specialist, non-allergist)
* Spirometry inconclusive

Exclusion Criteria:

* Use of an inhaled or systemic corticosteroid in the previous 48 hours;
* Smoking in the previous 6 hours; history of viral and/or bacterial respiratory infection in the past 4 weeks;
* major cardiopulmonary disease, including: a) chronic obstructive pulmonary disease (COPD), defined by all of the following: i) aged ≥ 40 years , ii) permanent obstruction on spirometry (FEV1/FVC \<0.7) and iii) a smoking history of \>10 pack-years or known alpha-1-antitrypsin deficiency, b) lung conditions deemed significant by the investigator, including cystic fibrosis and bronchiectasis, and c) unstable heart disease.

Where this trial is running

Montreal, Quebec and 2 other locations

• CHU Sainte-Justine — Montreal, Quebec, Canada (Not_yet_recruiting)
• Montreal Children's Hospital — Montreal, Quebec, Canada (Not_yet_recruiting)
• CIUSSS de l'Estrie - CHUS — Sherbrooke, Quebec, Canada (Recruiting)

Study contacts

• Study coordinator: Simon Couilard, MD MSc

Conditions Diagnosis; Inflammation; Asthma in Children; Asthma; observationnal study; asthma diagnosis; FeNO and eosinophil blood count; children