Abstract
Background: Although allergic rhinitis and asthma frequently coexist, the nature of this association is still not clearly identified.
Objective: To estimate the upper and lower airway inflammation in allergic rhinitis (AR) children with or without asthma in relation with bronchial responsiveness.
Methods: 145 children aged 7-12 years with AR alone or AR with asthma and 35 age-matched healthy controls were observed.
Lung functions, bronchial hyperreactivity tests (methacholine and exercise) nasal and induced sputum samples were performed in all patients. Total and antigen specific IgE, IL-5, IL-10, γ-IFN levels were assessed by ELISA.
Results: Children with AR alone (39%) but no clinical evidence of asthma showed increased nasal and induced sputum eosinophil counts and bronchial hyperreactivity to methacholine and exercise challenge compared with healthy control. In children with AR and asthma (61%) nasal and induced sputum eosinophilia and bronchial hyperresponsiveness were more significant compared with AR alone (p<0.05).
Remarkable, that blood eosinophil count, nasal and sputum eosinophilia were inversely correlated with bronchial hyperreactivity in all allergic patients. These parameters correlated with increasing production of IL-5, IL-10 and decreased gamma-IFN production and were more significant in AR with asthma children (p<0.05).
Conclusion: In children with AR without asthma subclinical changes in the lower airways and inflammatory mediators were detected. These data support the concept of significant links between upper and lower respiratory tract involvement in AR children with or without asthma and its association with bronchial hyperresponsiveness.
- © 2011 ERS