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Pneumonia

Pneumonia is a respiratory condition in which there is inflammation of the lung.

Community-acquired pneumonia refers to pneumonia in people who have not recently been in the hospital or another health care facility (nursing home, rehabilitation facility).

See also: Hospital-acquired pneumonia

Causes

Pneumonia is a common illness that affects millions of people each year in the United States. Germs called bacteria, viruses, and fungi may cause pneumonia.

Ways you can get pneumonia include:

Pneumonia caused by bacteria tends to be the most serious. In adults, bacteria are the most common cause of pneumonia.

Viruses are also a common cause of pneumonia, especially in infants and young children.

See also: Respiratory syncytial virus

Risk factors (conditions that increase your chances of getting pneumonia) include:

Symptoms

The most common symptoms of pneumonia are:

Additional symptoms include:

Exams and Tests

If you have pneumonia, you may be working hard to breathe, or breathing fast.

Crackles are heard when listening to your chest with a stethoscope. Other abnormal breathing sounds may also be heard through the stethoscope or via percussion (tapping on your chest wall).

The health care provider will likely order a chest x-ray if pneumonia is suspected.

Some patients may need other tests, including:

Treatment

Your doctor must first decide whether you need to be in the hospital. If you are treated in the hospital, you will receive fluids and antibiotics in your veins, oxygen therapy, and possibly breathing treatments. It is very important that your antibiotics are started very soon after you are admitted.

You are more likely to be admitted to the hospital if you:

However, many people can be treated at home. If bacteria are causing the pneumonia, the doctor will try to cure the infection with antibiotics. It may be hard for your health care provider to know whether you have a viral or bacterial pneumonia, so you may receive antibiotics.

Patients with mild pneumonia who are otherwise healthy are sometimes treated with oral macrolide antibiotics (azithromycin, clarithromycin, or erythromycin).

Patients with other serious illnesses, such as heart disease, chronic obstructive pulmonary disease, or emphysema, kidney disease, or diabetes are often given one of the following:

If the cause is a virus, typical antibiotics will NOT be effective. Sometimes, however, your doctor may use antiviral medication.

You can take these steps at home:

Outlook (Prognosis)

With treatment, most patients will improve within 2 weeks. Elderly or debilitated patients may need longer treatment.

Those who may be more likely to have complicated pneumonia include:

Your doctor may want to make sure your chest x-ray becomes normal again after you take a course of antibiotics. However, it may take many weeks for your x-ray to clear up.

Possible Complications

Possible complications include:

When to Contact a Medical Professional

Call your doctor if you have:

Infants with pneumonia may not have a cough. Call your doctor if your infant makes grunting noises or the area below the rib cage is retracting while breathing.

Prevention

Wash your hands frequently, especially after blowing your nose, going to the bathroom, diapering, and before eating or preparing foods.

Don't smoke. Tobacco damages your lung's ability to ward off infection.

Vaccines may help prevent pneumonia in children, the elderly, and people with diabetes, asthma, emphysema, HIV, cancer, or other chronic conditions:

If you have cancer or HIV, talk to your doctor about additional ways to prevent pneumonia and other infections.

Alternative Names

Bronchopneumonia; Community-acquired pneumonia

References

Higgins K, Singer M, Valappil T, Nambiar S, Lin D, Cox E. Overview of recent studies of community-acquired pneumonia. Clin Infect Dis. 2008;47:S150-156.

Centers for Disease Control and Prevention. Recommended Immunization Schedule for Ages 0 - 6 Years. United States, 2009.

Centers for Disease Control and Prevention. Recommended Immunization Schedule for Ages 7 - 18 Years. United States, 2009.

Centers for Disease Control and Prevention. Recommended Immunization Schedule for Adults. United States, 2009.

Li JZ, Winston LG, Moore DH, Bent S. Efficacy of short-course antibiotic regimens for community-acquired pneumonia: a meta-analysis. Am J Med. 2007;120:783-790.

Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis. 2007 Mar 1;44 Suppl 2:S27-72.

Update Date: 6/9/2009

Updated by: David A. Kaufman, MD, Section Chief, Pulmonary, Critical Care & Sleep Medicine, Bridgeport Hospital-Yale New Haven Health System, and Assistant Clinical Professor, Yale University School of Medicine, New Haven, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.


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