Pneumonia is an infection deep in the small airways and air sacs of the lungs. The infection will make the air sacs swell and fill with fluid or pus. This causes intense coughing. It will also be hard to breathe.
Development of Pneumonia in the Air Sacs of the Lungs
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Types of pneumonia include:
This article will focus on community-acquired pneumonia.
Pneumonia is caused by a germ in the air that you breathe. Germs that most often cause community-acquired pneumonia include:
Pneumonia is more common in older adults. Other factors that may increase the chances of pneumonia:
Health conditions that may increase the risk of community-acquired pneumonia include:
Other environmental factors include:
Pneumonia may cause:
The doctor will ask about symptoms and past health. A physical exam will be done. The doctor may suspect pneumonia based on symptoms and lung sounds.
Pictures of the lungs may be taken to confirm the diagnosis or check on pneumonia that is not going away. Pictures may be taken with:
Your doctor may need to know the exact germ that is causing the problem. This step may be needed if there is a severe infection. The germ can be tested through:
Treatment will be based on what may have caused the pneumonia. More support may be needed if there is a severe infection. A hospital stay may be needed if it becomes difficult to breathe.
Medicine can help to fight some infections:
Other medicine may help to manage symptoms:
Severe infections can make it hard for oxygen to get into the body. Oxygen may be given to improve levels in the blood.
Vaccines may help to prevent certain pneumonia:
Steps that may decrease the risk for any respiratory infection include:
American Lung Association
Centers for Disease Control and Prevention
Public Health Agency of Canada
The Lung Association
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Last reviewed March 2021 by
EBSCO Medical Review Board
David L. Horn, MD, FACP
Last Updated: 1/29/2021