What condition involves abnormal dilation of the bronchi accompanied by an accumulation of mucus?

The condition characterized by abnormal dilation of the bronchi, along with an accumulation of mucus, is bronchiectasis. This disorder occurs due to damage to the airway walls, often resulting from chronic infections, inflammation, or airway obstruction. The dilation of the bronchi leads to impaired clearing of mucus, creating an environment conducive to repeated infection and inflammation, which exacerbates the situation.

This accumulation of mucus is a hallmark of bronchiectasis, as the dilated bronchi cannot effectively transport mucus out of the lungs, leading to symptoms such as chronic cough, sputum production, and a higher susceptibility to respiratory infections. In contrast, other conditions listed do not primarily involve this specific pathology. For instance, asthma is characterized by reversible bronchoconstriction and inflammation, pneumonia involves inflammation of the lung parenchyma typically caused by an infectious agent, and COPD refers to a group of progressive lung disorders, primarily emphysema and chronic bronchitis, which have different pathological features. Therefore, the identification of bronchiectasis as the correct answer highlights its unique characteristics of bronchial dilation and mucus accumulation.