URL of this page: http://www.nlm.nih.gov/medlineplus/ency/article/007261.htm
Alternative names
Methicillin-resistant Staphylococcus aureus; Community-acquired MRSA (CA-MRSA); Hospital-acquired MRSA (HA-MRSA)Definition
Methicillin-resistant Staphylococcus aureus (MRSA) is an infection caused by a strain of Staphylococcus aureus (S. aureus) bacteria that is highly resistant to antibiotics.
Causes, incidence, and risk factors
S. aureus (“staph”) is a common bacteria that normally lives on the skin and sometimes in the nasal passages. MRSA refers to S. aureus strains that do not respond to the antibiotics normally used to cure staph infections.
The bacteria can cause infection when it enters the body through a cut, sore, catheter, or breathing tube. The infection can be minor and local (for example, a pimple), or more serious (involving the heart or bone).
Serious staph infections are more common in people with weak immune systems, usually patients in hospitals and long-term care facilities and those receiving kidney dialysis.
MRSA infections are grouped into two types:
Symptoms
Staph skin infections normally cause a red, swollen, and painful area on the skin. Other symptoms may include:
Symptoms of a more serious staph infection may include:
Signs and tests
Depending on the extent and severity of your symptoms, your doctor may recommend the following tests to detect and confirm the bacteria causing the infection:
Treatment
Draining the skin sore is often the only treatment needed for a local skin MRSA infection. This can be done at the doctor's office.
More serious MRSA infections, especially HA-MRSA infections, are becoming increasingly difficult to treat. Antibiotics that may still work include vancomycin (Vancocin, Vancoled), trimethoprim-sulfamethoxazole (Bactrim, Bactrim DS, Septra, Septra DS), linezolid (Zyvox), tetracycline (doxycycline), or clindamycin.
It is important to finish all doses of antibiotics you have been given, even if you feel better before the final dose. Unfinished doses can lead to development of further drug resistance in the bacteria.
Other treatments may be needed for infections that are more serious. The person will be admitted to a hospital. Treatment may involve:
Support Groups
For more information about MRSA, see the Centers for Disease Control web site: www.cdc.gov.
Expectations (prognosis)
How well a person does depends on the severity of the infection and their overall health. MRSA-related pneumonia and blood poisoning are associated with high death rates.
Complications
Serious staph infections may lead to:
Organ failure and death may result from untreated MRSA infections.
Calling your health care provider
Call your healthcare provider if a wound seems to get worse rather than heal, or if you have any other symptoms of staph infection.
Prevention
Careful attention to personal hygiene is key to avoiding MRSA infections.
References
Siegel JD, Rhinehart E, Jackson M, Chiarello L; Healthcare Infection Control Practices Advisory Committee. Management of multi-drug resistant organisms in healthcare settings, 2006. US Centers for Disease Control and Prevention. Accessed January 25, 2008.
Nicolle L. Community-acquired MRSA: a practitioner's guide. CMAJ. 2006;175:145.
Centers for Disease Control and Prevention. Epidemiology and management of MRSA in the Community. October 26, 2007. Accessed January 25, 2008.
Update Date: 1/25/2008 Updated by: D. Scott Smith, MD, MSc, DTM&H, Chief of Infectious Disease & Geographic Medicine, Kaiser Redwood City, CA & Adjunct Assistant Professor, Stanford University. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.