Gizycki M J, Hattotuwa K L, Barnes N, Jeffery P K
Lung Pathology Unit, Imperial College School of Medicine at the Royal Brompton Hospital, London, UK London Chest Hospital, London, UK.
Thorax. 2002 Sep;57(9):799-803. doi: 10.1136/thorax.57.9.799.
Inhaled corticosteroids (ICS) markedly reduce bronchial mucosal inflammation in asthma but whether they have an anti-inflammatory effect in airway tissue in chronic obstructive pulmonary disease (COPD) is unknown.
A study of endobronchial biopsy samples was conducted as part of a double blind, placebo controlled, randomised trial of parallel design. Patients had mild to moderately severe COPD (FEV(1) 25-80% of predicted) and were given 3 months treatment with ICS, fluticasone propionate (FP; 500 micro g twice daily, n=14) or placebo (n=10). Biopsy tissue taken at baseline and after treatment was examined by transmission electron microscopy to count the numbers of all ultrastructurally distinct inflammatory cells.
Compared with their baseline values, FP resulted in a significant decrease (on average 65%) in the numbers of mucosal mast cells (median 7.8 (range 1-33) v 2.8 (1-14), p<0.05). The reductive effect of FP held true when the post-treatment values of the placebo and FP groups were compared: 8.8 (1-24) v 2.8 (1-14) (p<0.05). Unexpectedly, there were significantly more neutrophils in the FP than in the placebo group: 4.0 (0-23) v 1.7 (0-8), respectively (p<0.05). There were no alterations to other cell types including mononuclear cells. Symptoms markedly improved in the patients treated with FP for 3 months.
Fluticasone propionate given for 3 months to patients with COPD has selective effects on the inflammatory cells in the bronchial mucosa: the reduction in mast cell numbers may account for the improvement in symptoms over this time.