Bronchitis
Acute bronchitis is a cough lasting up to about 3 weeks without pneumonia, per the CHEST Expert Panel Report. The cough itself can linger 6-8 weeks even after the infection resolves.
Symptoms
A persistent cough, sometimes with mucus production, mild chest discomfort from coughing, and occasionally a low-grade fever -- without the higher fever or focal findings of pneumonia.
Causes and risk
The large majority of cases are viral. Smoking and pre-existing lung disease can prolong or worsen the course.
How it is evaluated
Bronchitis is distinguished from pneumonia by vital signs and exam: a heart rate over 100, rapid breathing, temperature of 38°C or higher, or abnormal lung sounds point toward pneumonia and warrant a chest x-ray.
Treatment
Symptomatic care is standard. CHEST and ACP/CDC guidance both recommend against routine testing or antibiotics -- a Cochrane review found little benefit and a trend toward more side effects when antibiotics are given anyway. This guidance is for immunocompetent adults; children, pregnant patients, and immunocompromised or chronically ill patients may need individualized care.
When to seek care
Worsening shortness of breath, high fever, chest pain, or coughing up blood should prompt evaluation rather than continued home treatment -- these suggest something other than simple bronchitis.