MRSA

Causes

Most staph germs are spread by skin-to-skin contact (touching). A doctor, nurse, other health care provider, or visitors may have staph germs on their body that can spread to a patient.

Once the staph germ enters the body, it can spread to bones, joints, the blood, or any organ, such as the lungs, heart, or brain.

Serious staph infections are more common in people with a weakened immune system. This includes patients who:

• Are in hospitals and long-term care facilities for a long time
• Are on kidney dialysis (hemodialysis)
• Receive cancer treatment or medicines that weaken their immune system
• Inject illegal drugs.
• Had surgery in the past year

MRSA infections can also occur in healthy people who have not recently been in the hospital. Most of these MRSA infections are on the skin or less commonly lung infections. People who may be at risk are:

• Athletes and other people who may share items such as towels or razors
• Children in day-care
• Members of the military
• People who have gotten tattoos

Symptoms

It is normal for healthy people to have staph on their skin. Many of us do. Most of the time, it does not cause an infection or any symptoms. This is called “colonization” or “being colonized.” Someone who is colonized with MRSA can spread MRSA to other people.

A sign of a staph skin infection is a red, swollen, and painful area on the skin. Pus or other fluids may drain from this area. It may look like a boil. These symptoms are more likely to occur if the skin has been cut or rubbed because this gives the MRSA germ a way to “get in.” Symptoms are also more likely in areas where there is more body hair due to hair follicles.

MRSA infections in patients in health care facilities tend to be severe. These staph infections may be in the bloodstream, heart, lungs, or other organs, urine, or in the area of a recent surgery. Some symptoms of these severe infections are:

• Chest pain
• Cough or shortness of breath
• Fatigue
• Fever and chills
• General ill feeling
• Headache
• Rash
• Wounds that do not heal

Exams and Tests

Your doctor may order a “culture.” This is a sample from a wound, blood, urine, or sputum (spit). The sample is sent to the lab for testing. This testing can take a few days to finish.

Treatment

Draining a skin infection may be the only treatment needed for a skin MRSA infection that has not spread. A health care provider should do this procedure. Do not try to pop open or drain the infection yourself. Keep any sore or wound covered with a clean bandage.

Severe MRSA infections are becoming harder to treat. Your lab test results will tell the doctor which antibiotic will treat your infection. Your doctor will follow guidelines about which antibiotics to use and look at your personal health history. MRSA infections that are harder to treat are ones in:

• Lungs or blood
• People who are already ill or have a weak immune system

You may need to keep taking these antibiotics for a long time, even after you leave the hospital.

Support Groups

For more information about MRSA, see the Centers for Disease Control web site: www.cdc.gov/mrsa/.

Outlook (Prognosis)

How well a person does depends on the severity of the infection and their overall health. MRSA-related pneumonia and blood infections are associated with high death rates.

When to Contact a Medical Professional

Call your health care provider if you have any wound that seems to get worse instead of healing.

Prevention

The best way to prevent the spread of staph is for everyone to keep their hands clean. It is important to wash your hands properly.

• Health care workers and other hospital staff can prevent staph.
• Visitors also need to take steps to prevent spreading germs.

If you have surgery planned, tell your health care provider if:

• You have frequent infections
• You have had a MRSA infection before

Alternative Names

Methicillin-resistant Staphylococcus aureus; Hospital-acquired MRSA (HA-MRSA)

References

Fishman N, Calfee DP. Prevention and control of health care-associated infections.In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed.Philadelphia,PA: Saunders Elsevier; 2011:chap 290.

Centers for Disease Control and Prevention. Methicillin-resistant Staphylococcus aureus (MRSA) infections. Accessed April 17, 2011.

Que YA, Moreillon P. Staphylococcus aureus (including staphylococcal toxic shock). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 195.

Update Date: 4/9/2012

Updated by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.