Diagnostic Approach for Pediatric Asthma

Diagnostic Algorithm for Asthma in Children 5-16 Years

The European Respiratory Society recommends that the diagnostic approach for pediatric asthma should include spirometry, bronchodilator reversibility testing, and fractional exhaled nitric oxide (FeNO) measurement as first-line objective tests, while allergy testing should not be used to diagnose asthma but may be useful for management after diagnosis 1, 2
Recurrent wheeze, cough, and breathing difficulty are key symptoms of asthma, with wheeze being the most important symptom, and symptoms alone are insufficient for diagnosis; objective testing is required 3
Spirometry is strongly recommended as part of the diagnostic work-up, with FEV1/FVC <80% or <LLN, or FEV1 <80% pred supporting asthma diagnosis, and normal spirometry does not exclude asthma 1, 2
Bronchodilator Reversibility (BDR) Testing is strongly recommended in all children with abnormal spirometry, with an increase in FEV1 ≥12% and/or ≥200 mL after SABA inhalation being diagnostic of asthma, and BDR <12% does not exclude asthma 1, 4
FeNO Testing is strongly recommended as part of the diagnostic work-up, with FeNO value ≥25 ppb supporting asthma diagnosis, and FeNO <25 ppb does not exclude asthma 1, 2

The European Respiratory Society states that allergy testing is not recommended for asthma diagnosis, as skin-prick tests to aeroallergens have low specificity (23-40%) despite high sensitivity (77-90%), and specific IgE tests have low specificity (56-65%) 3, 7
Allergy testing is useful after asthma diagnosis for phenotyping the asthma, planning individualized prevention measures, and identifying potential allergic triggers 7
Skin-prick tests are considered positive with a wheal size of ≥3 mm compared to negative control, and specific IgE measurements have a cut-off for positive test commonly defined as <0.35 kU·L–1 7

The European Respiratory Society recommends that relying solely on symptoms for diagnosis leads to misdiagnosis, and using allergy tests alone to diagnose asthma will miss non-allergic asthma cases 7, 8
Multicomponent allergen-specific mitigation interventions are conditionally recommended for patients with symptoms related to specific indoor allergens, and integrated pest management is conditionally recommended for those with sensitization to pests 5