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Pneumonia is an infection in one or both lungs. The infection may be caused by fungi, bacteria, or viruses. Pneumonia causes inflammation in your lung’s air sacs, also referred to as alveoli. The alveoli fill with fluid or pus, making it difficult to breathe. Symptoms of pneumonia can range from mild to life threatening. In fact, pneumonia causes more deaths worldwide than any other illness. The severity of pneumonia usually depends on the cause of the inflammation or by the type of organism causing the infection, a person’s age, and their general health.
There are five major types of pneumonia. They are:
Bacterial pneumonia can affect anyone at any age. It can develop on its own or after a serious cold or flu. The most common cause of bacterial pneumonia is streptococcus pneumoniae. Bacterial pneumonia can also be caused by Chlamydophila pneumonia or legionella pneumophila. Pneumocystis jiroveci pneumonia is sometimes seen in those who have weak immune systems, due to illnesses like AIDS or cancer.
In most cases, respiratory viruses can cause pneumonia, especially in young children and the elderly. Pneumonia is usually not serious and lasts a short time. However, the flu virus can cause viral pneumonia to be severe or fatal. It’s especially harmful to pregnant women or individuals with heart or lung issues. Invading bacteria can cause complications with viral pneumonia.
Mycoplasmas are not viruses or bacteria, but they have traits common to both. They are the smallest agents of disease that affect humans. Mycoplasmas generally cause mild cases of pneumonia, most often in older children and young adults.
Many additional types of pneumonia affect immune-compromised individuals. Tuberculosis and pneumocystis carinii pneumonia (PCP) generally affect persons with AIDS. In fact, PCP can be one of the first signs of illness in people with AIDS.
Less common types of pneumonia can also be serious. Pneumonia can be caused by inhaling food, dust, liquid, gas, and by various fungi.
No one is immune to pneumonia, but there are certain factors that can raise your risks:
The general symptoms of bacterial pneumonia can develop quickly and may include:
Some symptoms may indicate a medical emergency. These symptoms include:
Pneumonia can be easily overlooked as the cause of an illness because it often resembles a cold or the flu. However, it usually lasts longer and symptoms seem more severe than these other conditions.
To determine whether or not a patient has pneumonia, doctors generally inquire about a patient’s signs and symptoms. Questions they may include:
Crackling and bubbling sounds in the chest during inhalation are usually indicators of pneumonia. Wheezing may also be present. Additionally, your doctor may have trouble hearing normal breathing sounds in different areas of the chest.
Chest X-rays can be used to determine if infection is present in your lungs. However, chest X-rays won’t show your type of pneumonia. Blood tests can provide a better picture of the type of pneumonia. Also, blood tests are necessary to see if the infection is in your bloodstream.
Additional tests that may be required include:
The type of treatment prescribed for pneumonia primarily depends on what type of pneumonia is present and its severity. In many cases, pneumonia can be treated at home.
The typical treatment plan for pneumonia includes taking all prescribed medications and participating in follow-up care. A chest x-ray may be ordered to ensure your pneumonia has been successfully treated.
Antibiotics are used to treat this type of pneumonia. Antibiotics should be taken as directed. If antibiotics are ceased before treatment is complete, the pneumonia may return. Most people will improve after one to three days of treatment.
Antibiotics are useless if a virus is the cause of pneumonia. However, antiviral drugs can help treat the condition. Symptoms usually improve within one to three weeks.
Anyone with diabetes, asthma, and other severe or chronic health problems, is at risk for pneumonia. However, in many cases, it can be prevented with vaccines against bacterial pneumonia and flu. Quitting smoking will definitely lower the risk of pneumonia.
Written by: Bree Normandin
Published on Aug 07, 2012
Updated on Feb 15, 2013
Medically reviewed by Brenda B. Spriggs, MD, MPH, FACP
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