Which of the following is a common cause of bronchiectasis?

• A. Tuberculosis
• B. Cystic fibrosis
• C. Asthma
• D. Bronchial asthma

Answer: (B)

Cystic fibrosis is a common cause of bronchiectasis because it leads to the production of thick and sticky mucus in the lungs, making it difficult to clear bacteria and debris. This accumulation can cause repeated infections and inflammation, ultimately damaging the airways and leading to bronchiectasis. In cystic fibrosis, the altered mucociliary clearance results in a chronic cycle of infection and inflammation, which progressively dilates the bronchi and causes the structural changes associated with bronchiectasis.

Other conditions, such as tuberculosis and certain types of asthma, can lead to airway damage, but they are not as commonly associated with bronchiectasis as cystic fibrosis. Tuberculosis might contribute to lung damage and bronchiectatic changes, but cystic fibrosis remains one of the primary causes due to the significant impact of its pulmonary complications.