Approximately 30 million annual clinic visits are attributed to cough in the United States. Moreover, evaluation and management of persistent cough in pulmonary clinics account for roughly 40% of patient volume. The most common etiologies are: Upper airway cough syndrome (UACS), asthma, non-asthmatic eosinophilic bronchitis (NAEB) and gastro-esophageal reflux disease (GERD) - all of which are treatable. However, despite avoidance of triggers and medical therapy, there remains an elusive diagnosis for some individuals with persistent cough. Further investigation warrants bronchoscopy, which is indicated for patients with persistent or unexplained cough.

The purpose of this study is to assess the diagnostic yield of fiberoptic bronchoscopy (FB) with Broncho-alveolar lavage (BAL) for chronic cough in patients with normal chest roentgenogram. FB records were reviewed in cohort for a period of 3 years. Only patients with normal chest roentgenograms who remained refractory to medical therapy were included in the study. Fifty-two (52) cases encompassing ages 20-90 were reviewed. In 42 cases, BAL was negative for any diagnostic cause. Eight (8) cases were significant for infectious processes, one (1) case diagnosed bronchiectasis, and 1 case was lost to follow-up. Statistical analysis between the total cases in each group was statistically significant p < 0.001. Thus, though FB with BAL is indicated in chronic cough of unknown etiology, its diagnostic yield is low.