Bronchial epithelium is already abnormal in children with severe asthma

Background: Airway epithelium remodelling is well described in severe asthmatic adults. Particularly, epithelium and basement membrane thickening as well as mucus cells hyperplasia are observed. However, few studies focused in severe asthmatics children. Aim: We aim to compare epithelial morphological features between severe asthmatic children and adults. Methods: Adults and children with severe asthma (according to GINA and American Thoracic Society criteria) underwent flexible bronchoscopy. Endobronchial biopsies from severe asthmatics adults and children were embedded in paraffin and specific stainings (PAS and Trichrome-Masson) were performed. Measurements of epithelium and basement membrane thickness and percentage of goblet cells were determined. Results: As expected, FEV1 is significantly higher in children (89.5% vs 66%, p=0.013) and treatment is different with no systemic corticotherapy in children. Results are presented in table 1. Epithelial and basal membrane thickness as well as percentage of goblet cells was comparable between adults and children. Conclusion: At present we did not find any major difference in epithelial structure between severe asthmatic children and adults. Epithelial functional features should be investigated to strengthen epithelial modifications are present from childhood.