What condition is characterized by irreversible dilatation and thickening of the bronchi?

The condition characterized by irreversible dilatation and thickening of the bronchi is indeed bronchiectasis. This pathological change occurs due to chronic inflammation and damage to the bronchial wall, which often results from recurrent respiratory infections or conditions that impair mucociliary clearance. The damaged airways fail to clear mucus effectively, leading to a cycle of infection and further airway damage, manifesting as dilated and thickened bronchi.

In bronchiectasis, patients typically experience chronic cough, production of large amounts of sputum, and frequent respiratory infections. Radiological findings would show dilated bronchi on imaging studies, affirming the diagnosis. This distinguishes bronchiectasis from other respiratory conditions, as it involves permanent structural changes in the airways, rather than just temporary inflammation or obstruction.