Bronchitis is an inflammation of the lining of your bronchial tubes, which carry air to and from your lungs. There are two main types of bronchitis: acute and chronic. Acute bronchitis, often caused by the same viruses that cause colds, usually starts as a sore throat, runny nose or sinus infection, and then spreads to your airways. It can cause a lingering dry cough, but it usually goes away on its own. In chronic bronchitis, a type of COPD (chronic obstructive pulmonary disease), the inflamed bronchi produce a lot of mucus, leading to cough and difficulty getting air in and out of the lungs.