RT Journal Article SR Electronic T1 Evidence of mast-cell activation in a subset of patients with eosinophilic chronic obstructive pulmonary disease JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 325 OP 331 DO 10.1183/09031936.02.00286302 VO 20 IS 2 A1 R.E. Louis A1 D. Cataldo A1 M.G. Buckley A1 J. Sele A1 M. Henket A1 L.C. Lau A1 P. Bartsch A1 A.F. Walls A1 R. Djukanovic YR 2002 UL http://erj.ersjournals.com/content/20/2/325.abstract AB Although asthma has been viewed mainly as an eosinophilic disease, and chronic obstructive pulmonary disease (COPD) as a neutrophilic disease, recent studies have shown increased neutrophil counts in severe asthma and sputum eosinophilia in some COPD patients. In an attempt to further characterise these two syndromes according to pathology, the current authors have conducted a study of induced sputum in 15 subjects with COPD, 17 asthmatics, and 17 nonatopic healthy individuals. Sputum was analysed for cytology and levels of eosinophil cationic protein (ECP), albumin, tryptase and soluble intercellular adhesion moleculeā€1. The COPD subjects differed from the asthmatics as they had higher sputum neutrophil and lower columnar epithelial cell counts, but there were no differences in any soluble marker studied. When compared to control subjects, both the asthmatic and COPD subjects had raised eosinophil counts and ECP levels. In a subset of COPD subjects with sputum eosinophilia (>3% of total cells), significantly increased levels of tryptase were detected. In conclusion, although chronic obstructive pulmonary disease is a more neutrophilic disease than asthma, the two diseases are difficult to distinguish on the basis of sputum levels of the soluble markers traditionally associated with asthma. However, a subset of patients with chronic obstructive pulmonary disease with airway eosinophilia and mast-cell activation might represent a distinct pathological phenotype.