Does prolonged cough mean lung disease ? i have been getting cough from 2 yrs now. it keeps coming every 2-3 months. also had tracheobronchitis once.

MAY NOT be Lungs: First: if you are smoker, please quit. Chronic cough may actually be due to post-nasal drip (in up to 50% of cases). Nasal drip could be due to sinus-allergy disease. A thorough history, exam, chest xray may be needed initially but you may need 'allergy testing' or imaging (e.g. Ct scans) to get the exact diagnosis. Further testing may include pulmonary function (pft). Hope you are better soon!

Chronic Cough: The type of cough you have fits the criteria of chronic cough, for it is lasting more than 8 weeks. Some common causes include post-nasal drip, asthma, acid reflux from stomach, medication (a specific groups of blood pressure medication), and smoking. There are plenty of other causes. So, prolonged coughing does not necessarily mean lung disease. Consider seeing a pulmonology or allergy specialist.