Clinical Course of Eosinophilic Bronchitis in Children / 소아알레르기및호흡기학회지

PURPOSE: It has been identified that eosinophilic bronchitis (EB) in adults can progress to asthma or fixed airway obstruction. In the present study, we evaluated the clinical course and prognosis of EB in children and their relationship with accompanying rhinosinusitis. METHODS: A total of 55 children with EB followed up for over than a year after the diagnosis were enrolled for the present study. We classified the subjects into two groups according to the prognosis and the presence of rhinosinusitis, respectively, and compared them with respect to clinical characteristics, eosinophil percentage in induced sputum, fractional exhaled nitric oxide (FeNO) and pulmonary function test. The poor prognostic group was defined as the children with asthma or asthma-like symptoms, or persistent or recurrent chronic cough in the long-term follow-up. RESULTS: The poor prognosis was achieved in 12 children (22%), and 3 children (5%) amongst them were diagnosed with asthma. There were no significant differences in clinical characteristics, eosinophil percentages in induced sputum, FeNO, spirometry and IOS according to the prognosis and the presence of rhinosinusitis. Additionally, the children with rhinosinusitis did not show any poorer outcome than those without rhinosinusitis. CONCLUSION: There were some limitations of this study for which the relationship between EB and rhinosinusitis in children was evaluated. However, in case of either poor short-term response to inhaled corticosteroids or elevated eosinophilic inflammation in airways or abnormal airway reversibility in impulse oscillometry, the long-term prognosis of EB in children needs to be considered, regardless of the presence of rhinosinusitis.

Exhaled Nitric Oxide is Associated with Allergic Inflammation in Children

Exhaled nitric oxide (eNO) has been proposed as a noninvasive marker of airway inflammation in asthma. In asthmatic patients, exhaled NO levels have been shown to relate with other markers of eosinophilic recruitment, which are detected in blood, sputum, bronchoalveolar lavage fluid and bronchial biopsy samples. The purpose of this study was to assess the possible relationship between eNO and allergic inflammation or sensitization in childhood asthma and allergic rhinitis. Subjects consisted of 118 asthmatic children, 79 patients with allergic rhinitis, and 74 controls. Their age ranged from 6 to 15 yr old. eNO level, peripheral blood eosinophil count, eosinophil cationic protein (ECP), serum total IgE level and specific IgE levels were measured. Methacholine challenge test and allergic skin prick test for common allergens were performed in all subjects. Atopic group (n = 206, 44.48 +/- 30.45 ppb) had higher eNO values than non-atopic group (n = 65, 20.54 +/- 16.57 ppb, P < 0.001). eNO level was significantly higher in patients with asthma (42.84 +/- 31.92 ppb) and in those with allergic rhinitis (43.59 +/- 29.84 ppb) than in healthy controls (27.01 +/- 21.34 ppb, P < 0.001) but there was no difference between asthma and allergic rhinitis group. eNO also had significant positive correlations with Dermatophagoides pteronyssinus IgE level (r = 0.348, P < 0.001), Dermatophagoides farinae IgE level (r = 0.376, P < 0.001), and the number of positive allergens in skin prick test (r = 0.329, P = 0.001). eNO had significant positive correlations with peripheral blood eosinophil count (r = 0.356, P < 0.001), serum total IgE level (r = 0.221, P < 0.001), and ECP (r = 0.436, P < 0.001). This study reveals that eNO level is associated with allergic inflammation and the degree of allergic sensitization.