RESUMEN
Airway wall remodeling is present in the airways of patients with COPD and is considered the most important contributor to the airflow limitation. To study the airway structural abnormalities and the role of mast cells in mild COPD. Thirty patients having mild COPD were subjected to sputum analysis and fiberoptic bronchoscopic biopsies from the main and segmental bronchi. BAL was obtained from segmental bronchi. At the level of mucosa there was infiltration by macrophages, lymphocytes and few numbers of neutrophils. Congestion, epithelial shedding and squamous metaplasia were more prevalent than in the central airways. At level of the submucosa there was goblet cell hyperplasia in 70% of cases. The muscle layer had an increased thickness in 80% of cases in comparison to 56.7% in the central airways and 83.3% showed thick fibrosed wall and shed epithelium in comparison to 40.0% in central airway. The pathological hallmark of COPD was mainly at the level of the small airways both at the level of the cellular components of BAL and at the level of histopathology