Inter-relationships between airway inflammation, reticular basement membrane thickening and bronchial hyper-reactivity to methacholine in asthma; a systematic bronchoalveolar lavage and airway biopsy analysis
Article first published online: 2 DEC 2005
Clinical & Experimental Allergy
Volume 35, Issue 12, pages 1565–1571, December 2005
How to Cite
Ward, C., Reid, D. W., Orsida, B. E., Feltis, B., Ryan, V. A., Johns, D. P. and Walters, E. H. (2005), Inter-relationships between airway inflammation, reticular basement membrane thickening and bronchial hyper-reactivity to methacholine in asthma; a systematic bronchoalveolar lavage and airway biopsy analysis. Clinical & Experimental Allergy, 35: 1565–1571. doi: 10.1111/j.1365-2222.2005.02365.x
- Issue published online: 2 DEC 2005
- Article first published online: 2 DEC 2005
- Submitted 21 May 2004; revised 14 July 2005; accepted 2 September 2005
- airway remodelling;
Background Asthma is accepted as a disease characterized by airway inflammation, with evidence that airway structural changes, or ‘remodelling’ occurs. There are few studies relating airway physiology, inflammation and remodelling, however. We have carried out a study of inter-relationships between airway inflammation, airway remodelling, reticular basement membrane (RBM) thickening, and bronchial hyper-reactivity (BHR), before and after high-dose inhaled corticosteroid (fluticasone propionate 750 μg b.d.), in a group of relatively mild but symptomatic, steroid naïve asthma patients.
Methods Double-blind, randomized, placebo-controlled, parallel group study of inhaled corticosteroid (ICS) in 35 asthmatics, with bronchoalveolar lavage (BAL) and airway endobronchial biopsy (EBB) for inflammatory cell profiles and EBB for airway remodelling carried out at baseline, 3 and 12 months.
Results At baseline RBM thickening was related to BAL mast cells and EBB eosinophil counts. In turn baseline log EBB EG2 eosinophil count, log%BAL epithelial cells and log RBM thickness explained 55% of the variability in BHR.
Conclusion We provide new information that airway inflammation, remodelling, and BHR in asthma are inter-related and improved by ICS therapy. Our data potentially support the need for early and long-term intervention with ICS even in relatively mild asthmatics, and the need to further assess the potential merit of longitudinal BHR testing in management of some patients, as this may reflect both airway inflammation and remodelling.