What is pneumonia?

Pneumonia is an infection in the lungs.

Pneumonia is an infection in the lungs. This can be caused either by viruses, bacteria, or by an organism called mycoplasma. When parents hear that their child has pneumonia, they often ask if the child will have to be admitted to the hospital. Most childhood pneumonia can be treated as an outpatient if diagnosed promptly.

Bacterial pneumonias are usually abrupt in onset with high fever. Usually a cough is present but sometimes the patient will have high fever and a stomachache as the lung sits over the stomach and causes irritation. Bacterial pneumonias also are usually associated with a high white blood cell count on a complete blood count (CBC). Once the correct antibiotic is started, the patient usually responds very quickly with fever diminishing in 24-48 hours. Cough may linger longer, though, from the irritation of the lung.

Viral and mycoplasma pneumonias are usually a little slower to develop and may not be associated with high fever. These pneumonias are often called "walking pneumonia" because the patient is usually not as sick as they are with bacterial pneumonias. It is often difficult to tell the difference between viral and mycoplasmal pneumonia. Both present with lower white blood cell counts and have a rather non-specific pattern on xRay. The only reason that it is good to know the difference is that viral pneumonia must be treated with supportive care while mycoplasmal pneumonia can be treated with antibiotics like Zithromax. Often, the only way to tell the difference is to try Zithromax and if the patient improves, it was probably a pneumonia caused by mycoplasma. If it was a viral pneumonia, the Zithromax will not help. Mycoplasmal infections are very common in younger school age kids.

Pneumonia is a lung condition in which the small air sacs (alveoli) and surrounding tissue become infected. In some instances fluid or pus occupy the air sacs. Pneumonia may manifest itself via severe coughing, abnormally high or low body temperature, and difficulty breathing. Pneumonia can have many different causes. It's often a complication of a pre-existing condition or an infection such as the flu. Pneumonia is a serious illness that is a common reason for hospitalization, especially in the very young and very old.

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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.