For more information contact:
Diane Smith
Director,
Patient Safety and Care Transitions
(248) 465-7329
dsmith@mpro.org
MRSA: Methicillin-Resistant Staphylococcus Aureus
Q: What is Staphylococcus aureus?
A: Stapylococcus aureus are bacteria commonly carried on the skin or in the nose
of healthy, often asymptomatic people. Most skin infections are minor pimples
and boils and can be treated, but staph bacteria can also cause surgical wound
infections, bloodstream infections and pneumonia.
Q: What is Methicillin resistant Staphylococcus aureus (MRSA)?
A: Some staph bacteria are resistant to antibiotics. MRSA is a type of staph that is
resistant to antibiotics called beta-lactams. Beta-lactam antibiotics include
methicillin and other more common antibiotics such as oxacillin, penicillin and
amoxicillin. While 25% -30% of the population is colonized with staph,
approximately 1% is colonized with MRSA.
Q: What does it mean if a patient is colonized?
A: Colonization refers to the presence of bacteria in or on a host with growth and
multiplication, but no tissue invasion or damage, no symptoms other than a
positive culture. Colonization can lead to infection, which is the entry and
multiplication of microorganisms in the tissues of the host, leading to local or
systemic signs and symptoms of infection.
Q: What is active surveillance and why is it important?
A: Many organizations such as The Centers for Disease Control and Prevention
(CDC) and The Society for Healthcare Epidemiology of America (SHEA)
recommend active surveillance of some or all patients for MRSA. A nasal swab is
collected and barrier precautions are initiated for all positive patients, even
those colonized. Another method used is to also isolate any patient with a
history of MRSA in the past, culture them and maintain isolation if positive.
Some populations can benefit from decolonization, like those facing surgery. The treatment might lessen the possibility of a surgical patient later developing
a wound infection, but colonization may persist in spite of treatment.
Q: When can a patient with MRSA be taken out of isolation?
A: There are no set protocols for removing contact precautions. Some hospitals
have adopted three negative cultures from the infected site as well as other at
risk sites, within a week, as a reasonable policy. Some facilities continue with
contact precautions.
Q: Which patients are at most risk for MRSA?
A: The population always thought to be most at risk is that group of patients living
in close quarters, who are elderly, those who are immune compromised, any
patient with a device such as a hip implant, or a long term ventilator, and
patients who have had a past history of MRSA. With the advent of
Community-acquired MRSA (CA-MRSA), there has been in increase in skin lesions in populations who have close skin-to-skin contact, openings in the skin such as
cuts or abrasions, contaminated items and surfaces, crowded living conditions
and poor hygiene. Athletic teams, prison populations and schools have seen
CA-MRSA outbreaks.
Q: How do we prevent the spread of MRSA?
A: Judicious use of antibiotics, the appropriate barrier precautions and rigorous
hand hygiene are the cornerstones of any program attempting to decrease the
incidence of MRSA cross contamination.
Q: Why is it important to monitor Vancomycin use?
A: With resistant staph, Vancomycin has been widely used to treat infections,
however, Vancomycin resistance has been in some bacterial strains. Avoiding
over-use is crucial. Some valid reasons to use Vancomycin for prophylaxis might
be the documentation of beta-lactam allergy, known, prior colonization with
MRSA, high risk due to acute inpatient stay in the past year, patient with LTC
setting within the last year, prior to admission, increased MRSA rate for facility or
specific procedure, documentation of chronic would care or dialysis, inpatient
stay longer than 24 hours prior to principal procedure.
Resources
Huang, Susan S, et al _Impact of Routine Intensive Care Unit Surfeillance Cultures and Resultant Barrier Precautions on Hospital-Wide Methicillin-Resistant Staphylococcus aureus Bacteremia,” Clinical Infectious Diseases October, 2006 43:971-8
Stokowski, RN, MS “Questions About MRSA and Answers From the Experts” Medscape Nurses Posted 11-1-2006, Accessed 1-23-2007 www.medscape.com
Kievens, R. Monina: et al “Community-associated Methicillin-resistant Stapylococcus aureus and Healthcare Risk Factors” Emerging Infectious Diseases 2006; 12(12):1991-1993 Posted 1-10-2007, Accessed 1-23-2007 www.medscape.com
CDC “Community-Associated MRSA Information for Clinicians” Released February 3, 2005. Accessed 1-19-2007, www.cdc.gov/ncidid/dhqp/ar_mrsa_ca_clinicians.html
