Comparison of Cytopathology between Nasal Secretion and Bronchoalveolar Lavage Fluid in Chronic Rhinosinusitis with Chronic Cough

Roh, Hwan Jung; Lee, Il Woo; Wang, Soo Geun; Kim, Chul Min; Lee, Min Ki; Park, Soon Gyu

Abstract

BACKGROUND AND OBJECTIVES
Postnasal drip is one of the most common symptoms of chronic rhinosinusitis (CRS), and is the main cause of chronic cough. To evaluate the effect of upper airway inflammation defined as CRS on lower bronchial airway, we compared the cytology of nasal secretion (NS) and bronchoalveolar lavage fluid (BALF) of normal controls and patients with chronic rhinosinusitis accompanying with and without chronic cough normal controls. MATERIALS AND METHOD: Ten patients of CRS with postnasal drip were selected. Five of them had chronic cough and the others not. Five normal controls were selected. NS collected using Juhn's tymanic tap and BALF collected through fiberoptic bronchoscopy were diluted with dithiothreitol and PBS. These samples were centrifused and then cytospin slide was prepared. The cytology of the slides were evaluated under light microscope after Wright stain. To examine neutrophil activity, nitroblue tetrazolium dye (NBT) test was performd. Statistical analysis was performed using Mann-Whitney Rank Sum W test. RESULTS: In NS, there were no significant differences in the cell populations among coughing, noncoughing, and the normal control group. NBT positivity of coughing (34.2%) and noncoughing (31.5%) groups showed significantly higher than those of controls (8.6%). In BALF of coughing group, the population of macrophages (78.0%) was significantly lower than noncoughing (86.6%) and control (92.8%) groups, and population of lymphocytes (20.8%) was significantly higher than noncoughing (12.6%) and the control (6.4%) groups. In BALF of noncoughing group, the population macrophages was lower and those of lymphocytes were higher than the control group. CONCLUSION: These results suggest that CRS enhances increased local immune responses and decreased phagocytic activity of the lower airway. And chronic cough in patients with CRS is thought to be dependent on individual tolerance to cough provocation, not on aspiration of postnasal drip of discharge.