Is this 15‑year‑old girl with recurrent episodes of bronchoconstriction, reversible small‑airway obstruction on spirometry, and normal skin‑prick test and total immunoglobulin E level having non‑atopic (intrinsic) asthma?

Yes, this is non-atopic (intrinsic) asthma

This 15-year-old girl meets diagnostic criteria for asthma based on recurrent bronchoconstriction and reversible small-airway obstruction on spirometry, and the negative skin-prick test with normal total IgE confirms the non-atopic phenotype. 1

Diagnostic Confirmation

The diagnosis of asthma in this adolescent is established through objective testing, independent of atopy status:

• Spirometry demonstrating reversible small-airway obstruction provides the key objective evidence required for asthma diagnosis in children aged 5-16 years 2, 1
• Recurrent episodes of bronchoconstriction represent the characteristic clinical pattern of asthma 2, 1
• The European Respiratory Society guidelines confirm that at least two abnormal objective tests (in this case: abnormal spirometry + positive bronchodilator reversibility) are sufficient to diagnose asthma 2, 1

Non-Atopic Classification

The negative allergy testing definitively classifies this as non-atopic asthma:

• Negative skin-prick tests and normal total IgE levels exclude atopic asthma and confirm the intrinsic (non-atopic) phenotype 3
• Non-atopic asthma accounts for 10-40% of all asthma cases 3
• The European Respiratory Society explicitly recommends against using allergy tests to diagnose asthma due to low specificity, but these tests are useful for phenotyping after diagnosis is established 2

Clinical Implications of Non-Atopic Asthma

Non-atopic asthma has distinct characteristics that guide management:

• Non-atopic asthmatics typically show more neutrophilic inflammation in younger patients (under age 50), though eosinophilic inflammation can develop with age 4
• This phenotype often presents with normal serum IgE but may still have local IgE production in airways 3, 5
• The inflammatory profile in bronchial mucosa is remarkably similar between atopic and non-atopic asthma, with comparable expression of eosinophilic markers (IL-3, IL-4, IL-5, IL-13, GM-CSF, RANTES) 3

Management Considerations

The non-atopic phenotype requires specific therapeutic approaches:

• Allergen avoidance strategies are not indicated since no specific allergens drive the disease 3
• Focus instead on avoiding nonspecific bronchial irritants including tobacco smoke, strong odors, and cold air 3
• Consider aspirin sensitivity and nasal polyposis, which occur more commonly in non-atopic asthma 3
• Standard inhaled corticosteroid therapy remains effective, as the airway inflammatory mechanisms are similar to atopic asthma 3, 6

Important Caveats

Several pitfalls should be avoided in managing this patient:

• Do not dismiss the asthma diagnosis simply because allergy testing is negative - asthma diagnosis is based on objective lung function testing, not atopy status 2, 7
• Non-atopic asthma may be associated with microbial superantigens (particularly Staphylococcal enterotoxins) that can amplify inflammation and reduce corticosteroid responsiveness 5
• This phenotype may be associated with more severe disease and corticosteroid dependence compared to atopic asthma 3
• The absence of atopy does not exclude eosinophilic airway inflammation, which remains a key feature requiring anti-inflammatory treatment 3, 4