Remodelling of the Lower Airways in Chronic Cough

Inclusion criteria for the study group: 1. age between 18 and 75 years, 2. chronic cough of at least one year duration, with no previous treatment (at least 2 previous unsuccessful attempts at pharmacological treatment of cough) 3. negative history of smoking (at least 6 months of abstinence), 4. negative history of treatment with angiotensin-converting enzyme inhibitors (ACEI), 5. normal chest radiograph or with changes not relevant to cough formation, 6. no respiratory tract infections in the past 6 weeks, 7. written consent from the patient to participate in the study. Exclusion Criteria: 1. patients less than 18 and more than 75 years of age, 2. cough lasting less than 12 months, 3. active smoking or abstinence period of less than 6 months, 4. respiratory tract infection 6 weeks prior to inclusion or at the time of study conduct - retry inclusion after 6 weeks, 5. cancer or interstitial lung disease, 6. contraindications to functional testing, sputum induction or bronchoscopy