acute bronchitis

Think of the bronchi as the main branching pipes that carry air deep into the lungs. In acute bronchitis these pipes become temporarily inflamed and irritated, usually by a virus, leaving their lining swollen and producing extra mucus. The result is a stubborn cough that can linger for weeks even after the person otherwise feels better — the pipes are sore, not the air sacs themselves.

Acute bronchitis is a self-limited inflammation of the bronchi, almost always triggered by the same respiratory viruses that cause colds and flu. The hallmark is cough, which may start dry and later bring up clear, yellow or green phlegm; the color of the phlegm does not reliably indicate bacterial infection. Mild wheeze, chest discomfort and a low fever can accompany it, but the lungs themselves remain clear of the consolidation seen in pneumonia.

Because it is overwhelmingly viral, antibiotics do not help most cases and are best avoided to limit side effects and resistance; treatment is supportive — fluids, rest, and sometimes remedies for cough or wheeze. The cough can persist for three weeks or more as the airway lining heals, which is normal and not a sign of treatment failure.

The main job of the assessment is to make sure the illness is not actually pneumonia, asthma or, in a smoker, a flare of chronic bronchitis — conditions that look similar at first but are managed quite differently.