Can HRCT be used as a marker of airway remodelling in children with difficult asthma?

Respir Res. 2006 Mar 27;7(1):46. doi: 10.1186/1465-9921-7-46.


Background: Whole airway wall thickening on high resolution computed tomography (HRCT) is reported to parallel thickening of the bronchial epithelial reticular basement membrane (RBM) in adult asthmatics. A similar relationship in children with difficult asthma (DA), in whom RBM thickening is a known feature, may allow the use of HRCT as a non-invasive marker of airway remodelling. We evaluated this relationship in children with DA.

Methods: 27 children (median age 10.5 [range 4.1-16.7] years) with DA, underwent endobronchial biopsy from the right lower lobe and HRCT less than 4 months apart. HRCTs were assessed for bronchial wall thickening (BWT) of the right lower lobe using semi-quantitative and quantitative scoring techniques. The semi-quantitative score (grade 0-4) was an overall assessment of BWT of all clearly identifiable airways in HRCT scans. The quantitative score (BWT %; defined as [airway outer diameter - airway lumen diameter]/airway outer diameter x100) was the average score of all airways visible and calculated using electronic endpoint callipers. RBM thickness in endobronchial biopsies was measured using image analysis. 23/27 subjects performed spirometry and the relationships between RBM thickness and BWT with airflow obstruction evaluated.

Results: Median RBM thickness in endobronchial biopsies was 6.7(range 4.6-10.0) microm. Median qualitative score for BWT of the right lower lobe was 1(range 0-1.5) and quantitative score was 54.3 (range 48.2-65.6)%. There was no relationship between RBM thickness and BWT in the right lower lobe using either scoring technique. No relationship was found between FEV1 and BWT or RBM thickness.

Conclusion: Although a relationship between RBM thickness and BWT on HRCT has been found in adults with asthma, this relationship does not appear to hold true in children with DA.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Adolescent
  • Asthma / metabolism
  • Asthma / pathology*
  • Asthma / physiopathology
  • Basement Membrane / metabolism
  • Basement Membrane / pathology*
  • Biopsy
  • Bronchi / metabolism
  • Bronchi / pathology
  • Bronchi / physiopathology
  • Child
  • Child, Preschool
  • Forced Expiratory Volume
  • Humans
  • Spirometry
  • Tomography, X-Ray Computed*