Thanks for your question. I am Dr Asanghanwa Carlson. Lung infections are due to the infectious agents like bacteria, viruses and fungi. A few conditions favour lung infections amongst these are smoking, alcoholism, exposing yourself to cold, and underlying immuno deficient conditions such as diabetes, HIV and other constitutive disorders. For your case, smoking favours the occurence of a chest infect and it can affect any lobe in your lungs though pulmonary tuberculosis has a predilection for the upper lung lobes. I would advise you to reduce and possibly stop smoking as this will expose to recurrent chest infections and possibly lung cancer. I will advise you visit a pneumologist for proper follow up. Have a great time