What chronic inflammatory disorder is characterized by irreversible dilation of the bronchi?

Bronchiectasis is indeed the chronic inflammatory disorder characterized by irreversible dilation of the bronchi. This condition arises due to a variety of underlying causes, including recurrent respiratory infections, chronic obstruction of airways, or genetic conditions like cystic fibrosis. The damage to the bronchial walls leads to chronic inflammation and the abnormal widening (dilation) of the airways, causing symptoms such as chronic cough, sputum production, and recurrent respiratory infections.

In contrast, asthma is primarily a reversible obstructive airway condition characterized by inflammation, bronchial hyperreactivity, and episodic obstruction, rather than permanent changes in bronchial structure. Pneumonia is an acute infection of the lung parenchyma rather than a chronic condition and does not lead to bronchial dilation. Chronic bronchitis involves chronic inflammation and mucus production in the airways, but while it can lead to airway obstruction, it does not specifically result in irreversible bronchi dilation like bronchiectasis does. Thus, the defining feature of bronchiectasis is its irreversible nature concerning bronchial dilation.