Abstract | BACKGROUND: In healthy adults and children, deep inhalation (DI) is able to reverse induced bronchoconstriction. This ability is impaired in asthma, but the reasons are still to be elucidated. OBJECTIVES: METHODS: The effect of DI on methacholine-induced bronchoconstriction was studied at the beginning and the end of a 3-month allergen avoidance period at high altitude in 14 allergic asthmatic children who had severe asthma attacks. Changes in airway caliber were inferred from the respiratory resistance (Rrs) measured by a forced oscillation technique. Results were related to the percentage of eosinophils in induced sputum and compared with those obtained in 9 age-matched nonasthmatic children. RESULTS: In asthmatic subjects, DI had no significant effect on methacholine-induced increase in Rrs before (P=.62) but significantly reversed it after (P <.01) allergen avoidance. However, the ability of DI to reverse a methacholine-induced increase in Rrs tended to remain less in asthmatic than nonasthmatic children even after allergen avoidance (P=.05). In the asthmatic children, the percentage of eosinophils in induced sputum was decreased at the end of the allergen avoidance period (P <.001), without any significant correlation between sputum eosinophils and airway responsiveness to methacholine or effect of DI. CONCLUSION: A short period of allergen avoidance may improve the ability of DI to reverse induced bronchoconstriction in some asthmatic children. This effect is associated, yet not correlated, with a reduction in airway inflammation.
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Authors | Manlio Milanese, Diego Peroni, Silvia Costella, Raffaele Aralla, Attilio Loiacono, Claudio Barp, Attilio Boner, Vito Brusasco |
Journal | The Journal of allergy and clinical immunology
(J Allergy Clin Immunol)
Vol. 114
Issue 3
Pg. 505-11
(Sep 2004)
ISSN: 0091-6749 [Print] United States |
PMID | 15356548
(Publication Type: Clinical Trial, Journal Article)
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Chemical References |
- Allergens
- Bronchoconstrictor Agents
- Bronchodilator Agents
- Dust
- Methacholine Chloride
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Topics |
- Administration, Inhalation
- Adolescent
- Allergens
(adverse effects)
- Animals
- Asthma
(drug therapy, physiopathology)
- Bronchial Hyperreactivity
(drug therapy)
- Bronchial Provocation Tests
- Bronchoconstrictor Agents
(administration & dosage, therapeutic use)
- Bronchodilator Agents
(administration & dosage, therapeutic use)
- Child
- Dust
(immunology)
- Eosinophils
(cytology)
- Female
- Humans
- Male
- Methacholine Chloride
(administration & dosage, therapeutic use)
- Mites
(immunology)
- Sputum
(immunology)
- Treatment Outcome
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