How is viral pneumonia differentiated from bacterial pneumonia?

Updated: Mar 24, 2021
  • Author: Zab Mosenifar, MD, FACP, FCCP; Chief Editor: John J Oppenheimer, MD  more...
  • Print

Studies document that patients are frequently infected with both bacterial and viral pathogens, making it impossible to rule out bacterial disease even when rapid viral test results are positive. Additionally, no unique identifying clinical characteristics are present that allow the physician to differentiate viral disease from bacterial disease in the emergency department (ED).

Although the most common cause of community-acquired pneumonia remains Streptococcus pneumoniae (a fact that may change with the increasing use of pneumococcal vaccines), in as many as 40-60% of patients with community-acquired pneumonia, the etiologic agent is not identified. Furthermore, convincing associations between the patient's symptoms, physical findings, laboratory test results, and specific etiologies are lacking.

Therefore, no way of accurately determining the etiology of pneumonia during the initial visit to the ED exists. Obtaining a chest radiograph in patients with suspected pneumonia is recommended, both to find complications, such as pleural effusions, and to discourage the use of antibiotics in healthy patients with bronchitis rather than pneumonia.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!