The cellular inflammation of bronchial biopsies in chronic obstructive pulmonary diseases

Abstract

This study was designed to describe the cellular inflammation, thickness of basement membrane (BMT) and epithelial desquamation (ED) in bronchial biopsies from patients with chronic obstructive pulmonary disease (COPD) compared with asthma and healthy individuals. Thirteen subjects with COPD, 12 asthmatic subjects, and 10 healthy individuals enrolled in the study. Bronchial biopsies obtained by fiberoptic bronchoscopy were stained with hematoxylin and eosin to perform cell counts and descriptive analysis. Neutrophils were found in higher numbers in epithelium and lamina propria in subjects with COPD compared with asthma and control groups (p< 0.001, p< 0.05) whereas eosinophils were observed higher in epithelium and lamina propria in asthmatic subjects (p< 0.001, p< 0.001). There were no significant differences in numbers of neutrophils and eosinophils in submucosa in the three groups (p> 0.05). There were no significant correlations between the inflammatory cell counts and FEV1 or smoking history in either group (p> 0.05). In subjects with COPD only 6 (46.2%) of the subjects showed BMT whilst 2 (15.4%) of the subjects showed ED. In asthma group, 11 (91.7%) of the subjects presented increased BMT and ED. In healthy individuals 1 (10%) of the subjects had increased BMT and no one had ED. As a result, we may conclude that the predominant cells of bronchial mucosa in COPD are the neutrophils whereas they are eosinophils in asthma. Thickening of basement membrane and epithelial desquamation are the major features of asthmatics. However in COPD, these features would be focally present and variable.