Eosinophilic Bronchitis (EB) is recognized as asthma-like eosinophilic inflammation, but it is different from asthma in terms of a lack of airway hyperresponsiveness. Pulmonary function test (PFT) is used for asthmatic children to diagnose and monitor the disease, but not for children with EB. So both spirometry and IOS (impulse oscillometry) were used for children with EB to assess their pulmonary function at the pre-/post- inhalation of bronchodilator (BD) and reversibility.
Methods
The subjects were children aged between 4 to 14 years: 71 with asthma, 51 with EB, 61 controls. At the pre-/post-inhalation of bronchodilator, we measured separately spirometry parameters (FVC, FEV1, PEF, MMEF) and IOS parameters (Resistence at 5 Hz [R5], R10, R20, R35, Average reactance [AX], X5).
Results
PreBD FEV1, preBD PEF and preBD MMEF of spirometry parameters in children with EB and controls were higher than in children with asthma (P < .001). However bronchodilator response of FEV1 (delta [d] FEV1) was significantly lower in children with EB and controls compared with asthmatic children (P = .014). PreAX and preX5 of IOS parameters showed lower in both children with EB and controls than asthmatic children (P < .001), but there was no difference in bronchodilator response (dAX and dX5). Asthmatic children in the pre-and post-inhalation of bronchodilator showed higher in AX, X5, R5, R10, R20, R35 and dAX compared with controls (P < .05), but no difference between controls and children with EB.
Conclusions
Asthmatic children showed a decrease in pulmonary function, but children with EB showed normal pulmonary function on spirometry and IOS.
Severance Children's Hospital, Yonsei University College of Medicine, Seoul, REPUBLIC OF KOREA
FULL TEXT