High-resolution computed tomography scan and airway remodeling in children with severe asthma

Background: Children with severe asthma have a significantly higher bronchial wall thickness (BWT) on high-resolution computed tomography scan than control children. Objective: We sought to determine whether a BWT score correlates with markers of airway remodeling and inflammation. Methods: In 37 children with severe asthma, we determined reticular basement membrane thickness; number of intraepithelial neutrophils and eosinophils on bronchial biopsy; IFN-gamma, IL-4, IL-5, and eosinophil cationic protein levels and IFN-gamma/IL-4 ratio on bronchoalveolar lavage specimen; and alveolar nitric oxide (NO) concentration and the maximum airway wall NO flux. Results: The BWT score significantly correlated with reticular basement membrane thickening (r = 0.34; P =.04) and NO production by the airway wall (r = 0.45; P =.02). The correlation with the eosinophil cationic protein level was just significant (r = 0.40; P =.05), whereas there was no correlation with IFN-gamma/IL-4 ratio (r = -0.31; P = .08). The BWT score did not correlate with FEV1 or forced expiratory flow at 25% to 75% of forced vital capacity. Conclusion: High-resolution computed tomography scan is a noninvasive technique that might be valuable for quantifying airway remodeling in children with severe asthma. The new generations of multislice computed tomography scanners will allow higher definition and lower radiation exposure and probably give a better assessment of airway remodeling and efficacy of treatment in children with asthma.