ERS 2021 guidelines: diagnosing asthma in children aged 5-16

Official guidelineEuropean Respiratory Society clinical practice guidelines for the diagnosis of asthma in children aged 5-16 years. ERS, 2021.
Read the official guideline · Checked for a newer edition on 2026-10-20
We do not reproduce the guideline text — this page is an independent summary.

Who it applies to

Children and adolescents aged 5-16 years presenting with symptoms suggestive of asthma in primary and secondary care settings.

Key recommendations

A structured clinical history and examination should be taken, but diagnosis should not rely on symptoms alone because wheeze, cough and breathlessness are nonspecific in this age group.
Spirometry should be performed as a first-line objective test, looking for an obstructive pattern.
Bronchodilator reversibility testing should be used to support the diagnosis when spirometry shows obstruction.
Where available, measurement of fractional exhaled nitric oxide (FeNO) should be used to help support a diagnosis of asthma by identifying eosinophilic airway inflammation.
Peak flow or spirometry variability monitored over time can be used to demonstrate variable airflow obstruction when initial tests are inconclusive.
Bronchial challenge testing can be considered in children who can perform the required technique when other tests are normal but clinical suspicion remains.
A trial of treatment may be used as part of the diagnostic pathway, but improvement in symptoms alone should not be considered sufficient confirmation of asthma.
Diagnostic algorithms should combine several tests rather than relying on any single test in isolation, since no single test has adequate accuracy alone.
The diagnosis should be periodically reconsidered, since asthma can be over- or under-diagnosed in children if tests are not re-evaluated.

What is new in this edition

Introduction of a more structured, algorithm-based diagnostic pathway combining objective tests rather than relying mainly on clinical judgement
Greater emphasis on FeNO as an adjunct diagnostic tool in children where available

Practice points for students

Do not diagnose asthma in a child based on wheeze history or response to bronchodilators alone; objective testing is required.
Spirometry with reversibility testing is the key first-line objective test in children old enough to perform it reliably.
FeNO is useful when available but is an adjunct, not a replacement for spirometry.
Reassess the diagnosis over time, as childhood asthma phenotypes can resolve or evolve.

Condition

Asthma