A bronchoscopic brush biopsy study of large airway mucosal pathology in smokers with chronic bronchitis and in healthy nonsmokers.

We investigated the use of bronchial brush biopsies of the bronchial epithelium as a diagnostic tool in common airway diseases. Flexible fibreoptic bronchoscopy was performed on 22 smokers with nonobstructive chronic bronchitis and on 14 healthy nonsmoking individuals. Ten of the smokers had recurrent infectious exacerbations. Cell samples were taken from carinal and subsegmental levels of the bronchial tree with a standard cytological brush, and a differential count was made of the different cell types. Smokers with chronic bronchitis had significantly more goblet cells (mean 20.0, SD 8.6), and less ciliated epithelial cells (mean 74.1, SD 9.4), than the healthy nonsmokers (mean 9.2, SD 3.9 and mean 84.7, SD 6.6, respectively). No such changes were found between the chronic bronchitis groups with or without infectious exacerbations. Thus, bronchial brush biopsies can be used as a complement to standard bronchial biopsies in the investigation of airway diseases other than pulmonary malignancies.