Title:A study of airway abnormalities and characterization of lesions at flexible bronchoscopy in Nepalese patients presenting with chronic cough with normal radiological imaging.

Background and Aims: Cough is one of the most common symptoms that lead patients to seek medical attention. The diagnosis of chronic cough is complex and challenging. Bronchoscopy can aid in the diagnosis of chronic cough by direct visualization of tracheobronchial tree and collecting specimens. Aim of the study was to determine the prevalence of the various tracheobronchial abnormalities in patients presenting with chronic cough with normal radiological imaging findings and to find out its relationship to histopathological findings and microbiological investigations.

Methods: This was a hospital based cross sectional study. The patients presenting with chronic cough (>8weeks) with normal radiological imaging were enrolled in the study.

Results: 30.8 percent patients had abnormal bronchoscopy findings, 23.1 percent patients had laryngeal abnormalities such as vocal cord and arytenoid congestion with nodule, 18 percent had tracheobronchial abnormalities such as 1 case of tracheomalacia, 1 case with endobronchial growth and 1 case of whitish plaque with narrowing of tracheobronchial tree. 74.4 percent had normal cellular pattern in BAL Cytology and 84.6 percent had normal endobronchial biopsy.

Conclusions: Based upon the findings of our study, we concluded that the description of a bronchoscopic anatomy-based diagnosis protocol for chronic cough could serve as effective method in diagnosis of the cause of chronic cough in Nepal.