What happens to the air passages in chronic bronchitis?

In chronic bronchitis, the air passages experience significant changes characterized by inflammation and irritation. This leads to an increase in mucus production, which can obstruct the airways. As a result, the bronchi become clogged with debris and excess mucus, making it difficult for air to flow in and out of the lungs. This condition is often exacerbated by factors such as smoking or exposure to pollutants, which can further stimulate mucus secretion and contribute to airway inflammation.

The blockage caused by excess mucus can lead to symptoms such as cough, wheezing, and difficulty breathing, especially during physical exertion. The long-term nature of chronic bronchitis means these changes can be sustained over time, leading to chronic respiratory issues.

In contrast, other options do not accurately reflect the pathological changes that occur in chronic bronchitis. The condition does not result in complete obstruction of the air passages, significant enlargement, or a lack of noteworthy changes; rather, it is specifically marked by mucus production and airway obstruction.