What causes pneumonia?

Dr. Kathleen Handal, MD
Emergency Medicine Specialist

Pneumonia is inflammation of lung tissue. You all realize organisms (bacteria, viruses, fungus and parasites) can get into our airways and inflame lung tissue causing cough trouble breathing less oxygen to rest of our body. Infection can enter through your blood or directly into our lungs. Also vomiting and 'aspirating' stomach contents (going 'down wrong pipe') can irritate and inflame our lungs. Children swallow objects that after being in lung will cause an inflammation. Inhaling irritants (including household cleaners) can cause our lung tissue to swell / inflame - pneumonia. Some of us are at increased risk for infections and specifically pneumonia. Chronic exposure to allergens toxins best example smoke can also inflame lung tissue allowing for your healthcare provider to hear abnormal sounds when using a stethoscope. You can have pneumonia days before a chest x-ray shows it! Be sure your provider listens to your lung fields - front and back in at least 8 areas and also asks you to say 'e' as he/she listens. You should have your mouth open and breath deep and not fast. When lung tissue is swollen (consolidated) 'e' will sound like 'a' thru the stethoscope. Remember if you are sent for an X-ray (plain film) to really take a deep breath otherwise you have been radiated for nothing. (Radiation dose from a chest film is 0.1 mSv or comparable to natural background radiation equal to 10 days of exposure.) A well preformed image must show at least 9 of your ribs to correctly evaluate the lung tissue underneath. If you have a 'documented' (on X-ray) pneumonia you should have a 'follow-up film to see how it resolved (yes you can hear the pneumonia is gone before the X-rays shows it is). Scar, calcification or other might remain - and you need to know this for the future.

Pneumonia is caused by germs. Germs that cause pneumonia are spread from person to person through things like coughing, sneezing, or by picking up germs on hands.

Pneumonia is a lung infection caused by viruses or bacteria (germs). It can be found either by a doctor listening to the chest or by an X-ray. Pneumonia is not easily passed from one person to another.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.