Diagnosis:

Doctors usually make a diagnosis of bronchitis based on the symptoms. Fevers that are high or prolonged or both could indicate the presence of pneumonia. Doctors may hear wheezing during the physical examination. A chest x-ray is sometimes done to exclude pneumonia, mainly when doctors hear wheezing or congestion in the lungs or when the person is short of breath.

A sample taken from the throat can be used to detect influenza. Sputum is generally only examined if doctors find evidence of pneumonia on a chest x-ray or during the examination. If a cough persists for more than 2 months, a chest x-ray is done to exclude an underlying lung disease, such as lung cancer.