Dec. 22, 2008 -- Question: What is the difference between bronchitis and pneumonia, and how does treatment differ?
Answer: Bronchitis is an inflammation of the bronchi, which are the large airway passages that lead from the mouth to the lungs -- and pneumonia is an infection of the lung tissue itself. The vast majority of patients who have bronchitis have it because they're exposed to a virus, most often the common cold.
Pneumonia can also be caused by a virus but also bacteria as well. Bronchitis usually is self-limited and requires no treatment at all when it's caused by a virus. Pneumonia, which is more often caused by bacteria, usually requires treatment with antibiotics.