Download methicillin-resistant staphylococcus aureus infections

METHICILLIN-RESISTANT STAPHYLOCOCCUS
AUREUS INFECTIONS
Dana Bartlett, RN, BSN, MSN, MA
Dana Bartlett is a professional nurse and author. His clinical experience
includes 16 years of ICU and ER experience and over 20 years of as a poison
control center information specialist. Dana has published numerous CE and
journal articles, written NCLEX material, written textbook chapters, and done
editing and reviewing for publishers such as Elsevire, Lippincott, and Thieme.
He has written widely on the subject of toxicology and was recently named a
contributing editor, toxicology section, for Critical Care Nurse journal. He is
currently employed at the Connecticut Poison Control Center and is actively
involved in lecturing and mentoring nurses, emergency medical residents and
pharmacy students.
ABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) causes nosocomial
and community-acquired infections that are associated with serious
morbidities and high mortality rates. It is resistant to many antibiotics.
It can cause skin infections, respiratory infections, sepsis, and
infections in most any organ system. MRSA has gathered significant
attention in the medical literature as the most common pathogen
causing surgical incision infections. The media has sensationalized
MRSA as the “superbug” and “flesh-eating bacteria”. The etiology,
transmission and treatment of MRSA is discussed.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
1
Continuing Nursing Education Course Director & Planners
William A. Cook, PhD,
Director, Douglas Lawrence, MS, Webmaster,
Susan DePasquale, CGRN, MSN, FPMHNP-BC, Lead Nurse Planner
Accreditation Statement
NurseCe4Less.com is accredited as a provider of continuing nursing
education by the American Nurses Credentialing Center's Commission
on Accreditation.
Credit Designation
This educational activity is credited for 1.5 hours. Nurses may only
claim credit commensurate with the credit awarded for completion of
this course activity.
Course Author & Planner Disclosure Policy Statements
It is the policy of NurseCe4Less.com to ensure objectivity,
transparency, and best practice in all Continuing Nursing Education
(CNE) activities. All authors and course planners participating in the
planning or implementation of a CNE activity are expected to disclose
to course participants any relevant conflict of interest that may arise.
Statement of Need
Staphylococcus aureus is a leading cause of morbidity and mortality.
All health professionals need to be informed of the cause, transmission
and treatment of MRSA infections in the health care and community
setting.
Course Purpose
This course will provide learning for nurses in all settings of MRSA
infections and the recommended treatment.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
2
Learning Objectives
1. Identify areas of the body where MRSA is commonly found.
2. Identify the two 2 categories of MRSA.
3. Identify why MRSA is resistant to many antibiotics.
4. Identify risk factors for developing a MRSA skin infection.
5. Identify why necrotizing fasciitis can be difficult to diagnose.
6. Identify three organ systems that can be affected by MRSA.
7. Identify how MRSA is transmitted.
8. Identify risk factors for transmission of MRSA in the community.
9. Identify the most common antibiotic used to treat MRSA infections.
10. Identify methods used to prevent the transmission of MRSA.
Target Audience
Advanced Practice Registered Nurses, Registered Nurses, Licensed
Practical Nurses, and Associates
Course Author & Director Disclosures
Dana Bartlett, RN, BSN, MSN, MA, William S. Cook, PhD,
Douglas Lawrence, MS, Susan DePasquale, CGRN, MSN, FPMHNP-BC
- all have no disclosures
Acknowledgement of Commercial Support
There is no commercial support for this course.
Activity Review Information
Reviewed by Susan DePasquale, CGRN, MSN, FPMHNP-BC
Release Date: 1/1/2015
Termination Date: 1/21/2016
Please take time to complete the self-assessment Knowledge Questions
before reading the article. Opportunity to complete a self-assessment of
knowledge learned will be provided at the end of the course.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
3
1. Staphylococcus aureus bacterium is:
a. a gram-positive organism
b. is not part of the normal human flora
c. commonly found in the stomach
d. affecting approximately 5 % of the population
2. True or False. Methicillin-resistant Staphylococcus aureus
has been found in significant amounts on stethoscopes.
a. True
b. False
3. Transmission of MRSA is primarily through:
a. blood contact
b. sputum contact
c. skin contact
d. gastric secretions
4. Patients with community-acquired or hospital-acquired
MRSA pneumonia should be:
a. treated with IV or PO clindamycin
b. treated with linezolid
c. treated with IV vancomycin
d. all of the above
5. The CDC recommends the use Standard Precautions to:
a. prevent transmission of MRSA
b. include hand hygiene, gloving, mouth, nose and eye
protection
c. use of a gown when needed
d. all of the above
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
4
INTRODUCTION
Methicillin-resistant Staphylococcus aureus (commonly known as
MRSA) is a strain of Staphylococcus aureus bacteria that is resistant to
many antibiotics. It can cause skin infections, respiratory infections,
sepsis, and infections in essentially any organ system. Methicillinresistant Staphylococcus aureus has gathered significant attention in
the medical literature because it causes nosocomial and communityacquired infections that are associated with serious morbidities and
high mortality rates, and it is the most common pathogen causing
surgical incision infections. This bacterium has also attracted much
attention in the public sector because it has been sensationalized in
the popular media as the “superbug” and as the “flesh-eating bacteria”
that causes necrotizing fasciitis.
Necrotizing fasciitis is a relatively rare pathology, and it can be caused
by other pathogens, but nonetheless MRSA is a dangerous bacterium.
It is endemic in healthcare facilities, there is evidence that the
incidence of community-acquired MRSA infections is rising, and there
is no doubt that MRSA-related infections are associated with poor
outcomes. Fortunately, with timely identification and proper treatment,
MRSA-related infections can be successfully treated and with good
infection control the transmission of MRSA can be significantly
reduced.
THE STAPHYLOCOCCUS AUREUS BACTERIUM
The Staphylococcus aureus bacterium is a gram-positive organism that
is part of the normal human flora. It is commonly found on the skin
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
5
and approximately 25% to 50% of the population may be
asymptomatic carriers at any one time and have the bacterium on
their skin, either chronically or transiently: colonization with
Staphyloccus aureus is more common in insulin-dependent diabetics,
people who are infected with HIV, people who need hemodialysis on a
chronic basis, and people who have damaged skin.1 Methicillinresistant Staphylococcus aureus is commonly found in the anterior
nares, the vagina, the axilla, the perineum, and the oropharynx.
(Note: Colonization is the implantation and growth of a microorganism
on a host).
Staphylococcus aureus has long been known to be a dangerous
pathogen, not particularly because of its inherent virulence but
because of its ability to establish itself in human hosts. All bacteria and
viruses have the capability of causing harm and evading host
defenses, but Staphylococcus aureus is especially well suited to do so
because these attributes are well developed in the bacterium.
Specifically, Staphylococcus aureus and MRSA both:2-4

Have a strong ability to evade host defenses. This is
accomplished through several mechanisms: forming a
microcapsule around itself; expression of protein A, a surface
protein that can act to disguise Staphylococcus aureus from the
host’s immune system and help the bacterium resist
phagocytosis, and; the presence of coagulase, an enzyme that
also helps the bacterium resist phagocytosis.

Can use enzymes such as hyaluronate lyase, protease, and
staphylokinase to break through tissues to establish infection.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
6

Produce cytotoxins, pyrogenic toxins, and exfoliative toxins.

Have the ability to survive for up to 6 months on medical
equipment, gloves, hard surfaces, etc.
Methicillin-resistant Staphylococcus aureus has an additional attribute
that makes this bacterium particularly dangerous; it cannot be treated
with many of the commonly used antibiotics. The bacterium has a
protein on the cell wall - the penicillin-binding protein - that has a very
low affinity for the β-lactam antibiotics,5 and the penicillins and
methicillin are β-lactam antibiotics. The β-lactam antibiotics work by
binding to the penicillin-binding protein on a bacterium and disrupting
the synthesis of the cell walls. Methicillin-resistant Staphylococcus
aureus cannot be treated with β-lactam antibiotics because the
bacteria have developed a penicillin-binding protein that does not allow
this adhesion of the antibiotics to the cell wall of the bacterium.
Because of this, MRSA cannot be treated with the penicillins and
methicillin and many of the strains of MRSA are resistant to
aminoglycosides (i.e., gentamicin, streptomycin), cephalosporins (i.e.,
cephalexin,
cefoxitin),
fluoroquinilones
(i.e.,
ciprofloxacin,
levofloxacin), lincosamides (i.e., clindamycin), and macrolides (i.e.,
azithromycin, clarithromycin).
Knowledge Check:
Methicillin was developed after penicillin and it is in the penicillin class of antibiotics.
Methicillin is no longer manufactured - other antibiotics were found to be more
effective and more stable - but the term methicillin-resistant is still used to describe
strains of Staphylococcus aureus that are resistant to penicillins.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
7
EPIDEMIOLOGY OF MRSA INFECTIONS
Although MRSA has been much in the minds of healthcare
professionals for many years, penicillin-resistant and methicillin
resistant strains of Staphylococcus aureus are not new and were
identified just a few years after these antibiotics were first widely used
during the mid 20th century or so (in the case of MRSA, 1961). But
despite over 50 years of anti-microbial therapy and vigorous efforts at
infection control, MRSA infections are still quite common. Methicillinresistant Staphylococcus aureus is the most common antimicrobialresistant pathogen found in the United States, Europe, and many other
parts of the world,6 it is the most common cause of surgical site
infections,7 and it is the second-most common cause of bacteremia.8
Up until the late ‘90s, MRSA had been seen only in healthcare settings
and it was considered to be a nosocomial infection that occurred in
patients who had specific risk factors, but in 1999 the first confirmed
cases of community-acquired MRSA were found in the US.9 In recent
years the incidence of hospital-acquired MRSA has been declining,10
but the incidence of community-acquired MRSA has been increasing,
and there is speculation that the community acquired type of MRSA
will become the dominant form.11,12 Community-acquired MRSA is a
different strain than hospital-acquired but there is evidence that the
line between the two has become somewhat blurred and cases of
community-acquired MRSA are increasingly being seen in the
healthcare setting.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
8
METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS
INFECTIONS
Methicillin-resistant Staphylococcus aureus can produce an infection in
many different organs and organ systems. Approximately 95% of
infections caused by the community-acquired strains of MRSA involve
the skin or soft tissue, approximately 2-4% involve a bone or a joint:
the respiratory tract, urinary tract, and other sites of infection each
account for 1% or less of community-acquired MRSA infections.13
Hospital-acquired MRSA infections also involve the skin, the bones and
joints, the respiratory tract, the urinary tract, and cause bacteremia
and sepsis, as well.14
Skin and soft tissue infections
Skin and soft tissue infections caused by MRSA include carbuncles,
cellulitis, impetigo, folliculitis, furuncles, mastitis, and surgical wound
infections. Methicillin-resistant Staphylococcus aureus is the leading
cause of surgical wound infections after cardiac, orthopedic, trauma, or
vascular surgery,15,16 it is the most common cause of surgical wound
infections, and surgical wound infections with MRSA are the most
common hospital-acquired MRSA infections.17
Skin infections caused by MRSA are more common in hospital patients
if the patient: 1) is immunocompromised; 2) has an in-dwelling
catheter; 3) has received multiple antibiotics; 4) has a prolonged stay;
5) was admitted to an ICU, or; 6) previously lived in a community
residential living facility.18,19 Community-acquired MRSA skin infections
are more likely to occur in children, military personnel, people who are
incarcerated, people who have insulin-dependent diabetes, IV drug
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com
9
users, athletes who play team sports (especially contact sports such as
wrestling), men who have sex with men, and people who are
immunocompromised.20,21
Knowledge Check:
A MRSA infection can be caused by someone’s own skin flora or from pathogens
transmitted to that person from someone else or a contaminated environment.
Necrotizing fasciitis
Necrotizing fasciitis is a rare and very dangerous skin infection that
can be caused by MRSA, as well as by other pathogens. The exact
incidence of MRSA as the pathogen responsible for necrotizing fasciitis
is not known, but a recent study found that 39% of the cases
examined were caused by MRSA.22 Many patients with necrotizing
fasciitis first complain of fever and intense pain, and then develop skin
changes that can be mistaken for cellulitis, deep vein thrombosis, a
hematoma, phlebitis, or other local or systemic pathologies.23
Risk factors for adults for developing this infection include diabetes
mellitus, IV drug use, peripheral vascular disease, and smoking.24 For
children, the risk factors include chronic illness, recent infection with
varicella, surgery, and trauma.25 Although there may be some skin
changes and lesions caused by necrotizing fasciiitis, the major tissue
damage is subcutaneous, so the initial presentation - intense pain combined with the lack of skin damage or the lack of dramatic skin
lesions and the non-specific laboratory findings make necrotizing
fasciitis difficult to diagnose. However, early diagnosis is crucially
important as the disease is rapidly progressive and potentially very
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 10
dangerous: tissue necrosis can occur at 1 inch every hour26 and
mortality rates of 20-80% have been reported.27
Respiratory tract infections
Methicillin-resistant Staphylococcus aureus has been noted to be the
causative pathogen in 15-27% of ventilator-associated pneumonia and
healthcare-associated pneumonia.28 Pneumonia caused by communityacquired MRSA is much less common (there are no reliable estimates
of its incidence), but it is a serious disease and the mortality rate is
very high.29
Bone and joint infections
Methicillin-resistant Staphylococcus aureus is an infrequent cause of
osteomyelitis and septic arthritis. Most reported cases of septic
arthritis caused by MRSA are nosocomial infections, the patients are
adult males, and they have pre-existing rheumatic disease. Septic
arthritis can be caused by a MRSA soft tissue infection that spreads, it
can cause extensive joint destruction, and the mortality rate is
approximately 16%.30 Osteomylelitis caused by MRSA is more common
in children.31
Bacteremia and sepsis
Staphylococcus aureus is the second leading cause of blood stream
infections, and it is the leading cause of sepsis in patients in ICUs.32,33
Bacteremia caused by MRSA has been associated with a mortality rate
of approximately 32%.34
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 11
Infections caused by MRSA can also affect the urinary tract, the eyes,
and the heart (infective endocarditis), and cause toxic shock
syndrome.
HOW MRSA INFECTIONS BEGIN AND BECOME ESTABLISHED
There are essentially two stages of a Staphylococcus aureus infection:
1) exposure to the pathogen and establishment of a local infection,
and; 2) evading the host’s immune response.
Exposure to MRSA/Establishment of Infection
Exposure to MRSA can be from the patient’s normal flora or exposure
to a colonized person or a contaminated environment. The incidence of
colonization with Staphylococcus aureus in the general population is
approximately 25-50%. The incidence of colonization with MRSA is
lower and it varies widely. Exact figures are not available, but recent
studies noted that 0.084% to 16.1% of the population had colonization
of MRSA,35,36 although the typical colonization rate is approximately 510%.37 Advanced age, previous exposure to antibiotics, and previous
admissions to the hospital are common factors that increase the risk of
MRSA colonization.
Knowledge Check:
Colonization and infection are not the same. People can be colonized with MRSA for
months and years but they may not - and often do not - develop an infection. Most
people who are colonized with MRSA are colonized at multiple sites, and 80-95%
of people who are MRSA carriers are asymptomatic.38
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 12
Contamination is a significant risk in the healthcare setting. Methicillinresistant Staphylococcus aureus has been found in significant amounts
on stethoscopes,39,40 mobile phones belonging to healthcare personnel,
patients and visitors,41,42 x-ray cassettes,43 and surfaces such as cloth
curtains, computer keyboards, countertops, glass, and tile.44
The infection is established when the integrity of the skin is broken,
i.e., by an abrasion, IV catheter insertion, or any medical procedure
and the bacterium has a point of entry to the tissue and/or
bloodstream.
Evasion of Host Immune Response
Once the bacteria have access to the tissue or the bloodstream they
begin
to
replicate.
Staphylococcus
aureus
and
MRSA,
as
was
mentioned previously, are well equipped to evade host defenses, and
they do so by forming a microcapsule around the bacterium that
protects them from host response, expression of protein A, a surface
protein that can act to disguise Staphylococcus aureus from the host’s
immune system and help the bacterium resist phagocytosis, and using
enzymes that help the bacterium resist phagocytosis and break down
tissues.
TRANSMISSION OF MRSA
Transmission of MRSA is primarily through skin contact. The bacteria
can be carried or transmitted from an infected person to someone
else, or it can be transmitted from an infected object in the
environment; and, the latter is thought to be a much less common
mode of transmission. In the healthcare setting, patients are the
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 13
primary source of MRSA, and transmission of MRSA primarily occurs by
the bacterium being carried from one patient to another by healthcare
personnel. The risk of this is relatively high: studies have shown that
MRSA is transmitted from infected patients to the gloves of healthcare
workers in approximately 17% of all contacts.45 Even in relatively
“clean” patient care contact situations, MRSA can easily colonize the
skin, gloves, or clothing of nurses, physicians, etc. Methicillin-resistant
Staphylococcus aureus can also be transmitted by infected droplets
that are exhaled by an infected person.
Knowledge Check:
It was mentioned in a previous section of this module that MRSA can persist in the
environment for many months, and MRSA is very common in the environment. A
2012 study found that 11.8% of surfaces tested in three community hospitals were
contaminated with MRSA.46
In the community, as in the healthcare setting, MRSA is transmitted by
contact with an infected person or their clothing or a contaminated
object, and a community-acquired MRSA infection is the result of one
or more of the “five Cs”:

Crowding

Contact

lack of Cleanliness

environmental Contamination

Compromised skin
Children, military personnel, people who are incarcerated, people who
have diabetes, people who use IV drugs, athletes who play team
sports (especially contact sports such as wrestling), men who have sex
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 14
with men, and people who are immunocompromised often have one of
these five Cs operating in their personal lives or their health status, so
they are especially at risk for contracting a MRSA infection.
TREATMENT OF MRSA INFECTIONS
The following treatment recommendations were developed by the
Infectious Diseases Society of America,47 and they are also used by
the Centers or Disease Control and Prevention (CDC). They can be
viewed on the website of Infectious Diseases Society of America,
http://www.idsociety.org/Organism/ or from a link on the CDC
website, www.cdc.gov. The recommendations, including the supporting
references, are 39 pages long and they will not be covered here in
their entirety.
Treatment of Skin and Soft Tissue Infections
Cutaneous abscess:
For adults, incision and drainage should be performed; this is the first
step in treatment. After this has been done, antibiotic therapy should
be started if the patient: 1) has severe and/or extensive disease (i.e.,
multiple sites of infection); 2) has an infection that is rapidly
progressing; 3) has cellulitis; 4) has signs or symptoms of a systemic
illness caused by the infection; 5) is immunosuppressed; 6) has
significant co-morbidities; 7) is very young or very old; 8) has an
abscess in an area that is difficult to incise and drain, i.e., the face,
hands, genitals, or; does not respond to incision and drainage.
Outpatients can be empirically treated with clinadamycin,
trimethoprim-sulfamethoxazole, a tetracycline, or linezolid.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 15
Hospitalized patients with a skin or soft-tissue infection can be
empirically treated with IV clindamycin, daptomycin, linezolid,
telavancin, or vancomycin. Surgical debridement may be needed for
extensive infections. Children who have a minor lesion can be treated
with 2% mupirocin topical ointment. If systemic antibiotics are
needed, clindamycin, linezolid, or vancomycin can be used.
Tetracycline should not be used in children less than 8 years.
Knowledge Check: It was mentioned in a previous section that MRSA is resistant
to lincosamides such as clindamycin. This is true is some circumstances, but in
treating some MRSA infections clindamyicn can be effective and is used.
Bactermia and endocarditis:
Adults who have uncomplicated bactermia should be treated with IV
daptomycin or vancomycin for at least two weeks. Adults who have
complicated bacteremia should be treated with daptomycin (possibly
at higher doses than would be used to treat uncomplicated
bacteremia) or vancomycin for four to six weeks. All of these patients
should have an echocardiogram. Cases of infective endocarditis should
be treated with daptomycin or vancomycin for six weeks. If the patient
has a prosthetic valve and infective endocarditis, the patient should be
treated with vancomycin, gentamicin, and IV or PO rifampin.
Children who have, or are suspected to have, bacteremia, infective
endocarditis, or have a prosthetic heart valve and have infective
endocarditis caused by MRSA are treated with the same drugs (albeit
at lower doses) as adults. The recommendations for the use of other
antibiotics, the duration of therapy, and the need for other treatments
and tests in children who have bacteremia or infective endocarditis are
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 16
quite extensive and will not be covered here: refer to the guidelines
for specific information.
Pneumonia:
Patients who have community-acquired or hospital-acquired MRSA
pneumonia should be treated with IV or PO clindamycin or linezolid or
IV vancomycin. Pediatric cases should be treated with the same drugs.
The treatment course should be 7-21 days, depending on the extent of
the infection.
Osteomyelitis:
Surgical debridement and drainage of soft tissue abscesses should be
done. The optimal antibiotic therapy has not been determined, but IV
daptomycin or vancomycin are typically used. The patient can also be
treated with a combination of PO and IV drugs, i.e., clindamycin,
linezolid, trimethoprim-sulfamethoxazole, and rifampin. Children are
treated with the same drugs, but trimethoprim-sulfamethoxazole is not
used. The optimal duration of treatment for MRSA-related
osteomyelitis has not been determined, but the guidelines recommend
at least eight weeks of antibiotic therapy and some authorities
recommend one to two months of treatment after those eight weeks.
The duration of antibiotic therapy for children should be four to six
weeks.
Septic arthritis:
The affected joint should be debrided and drained, and the patient
should be treated using the same regimen as would be used for a
patient with MRSA-related osteomyelitis. The duration of therapy
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 17
should be three to four weeks. If the affected joint has a prosthetic
device, the treatment is essentially the same as that for osteomyelitis,
but the location of the prosthetic device, how long it has been in place,
and the duration of the infection will be the factors that will determine
what antibiotics will be used and for how long. The treatment of
children with MRSA-related septic arthritis is essentially the same as
that for adults, but the duration of therapy should be a minimum of
three to four weeks.
Central nervous system infections:
Treatment recommendations are available for MRSA-related brain
abscess, meningitis, subdural empyema, spinal epidural abscess, and
septic thrombosis of the cavernous or dural venous sinus. In most
cases incision and drainage is recommended and IV vancomycin is the
preferred antibiotic. Rifampin may be added in some cases, and
linezolid or trimethoprim-sulfamethoxazole can also be used instead of
vancomycin. The duration of therapy can be two weeks (meningitis) to
four to six weeks. Children with these pathologies should be treated
with IV vancomycin.
Vancomycin has become the mainstay of antibiotic therapy for many
types of MRSA infections. This module will not cover the basics of
administration, adverse effects, and dosing, but two aspects of use
should be mentioned. There is some evidence that vancomycin can be
neprhotoxic, so dosing adjustments will need to be made and serum
trough levels will need to be measured and monitored if the patient
receiving vancomycin has renal impairment, if the patient is obese, or
if the patient has a serious infection. (Note: Vancomycin doses are
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 18
determined by body weight, so people who are obese will be given
large doses).
Dosing adjustments are made by obtaining trough levels of
vancomycin. Trough levels should be measured after the fourth or fifth
dose and immediately prior to the administration of that dose. A
trough level of 15-20 mcg/mL is considered optimal. If the patient is
not obese, does not have renal impairment, or has a relatively
uncomplicated infection, trough levels do not need to be measured.
PREVENTION OF TRANSMISSION
Preventing transmission of MRSA is critically important, and as nurses
have extensive patient contact they must understand and practice
good infection control. It has been clearly shown that conscientious
use of infection control practices - especially hand washing - can
reduce the transmission of MRSA.48-50
The CDC recommends the use Standard Precautions to prevent
transmission of MRSA,51 i.e., hand hygiene, gloving, mouth, nose and
eye protection, the use of a gown when needed, and the appropriate
handling and disposal of contaminated items. The CDC also
recommends using Contact Precautions “ . . . when the facility (based
on national or local regulations) deems MRSA to be of special clinical
and epidemiologic significance.” Contact Precautions are Standard
Precautions plus additional considerations regarding patient
placement, patient transport, and environmental activities.52
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 19
Knowledge Check: Preventing the transmission of MRSA can also be important in
the community. Some MRSA infection such as simple soft tissue infection can be
treated at home, or the initial treatment can be in a healthcare facility and
continued in the home setting. Patients and their family or close contacts will need
to be taught basics of infection control such as wound care, hand hygiene, surface
disinfecting, nasal decolonization with mupirocin, etc. This issue is covered on the
website of the Infectious Diseases Society of America and their recommendations
are available though this link.
http://www.idsociety.org/Organism.
Prevention of transmission of MRSA can be accomplished by identifying
and decolonizing people who are carrying MRSA. However, at this
point, the benefits of screening and decolonization have not been
conclusively proved.53,54 Screening of patients who are likely to be
carriers may be helpful and is often done, but screening of all patients
seems unlikely to do more than increase health care costs.55 Also,
although colonization by MRSA increases a patient’s risk for developing
a MRSA-related infection, it is also not clear that decolonization of
MRSA from people who are carriers decreases transmission rates or
the incidence of infection.56,57 Screening for MRSA is done by swabbing
the nostrils, the perineal area, and the skin (where appropriate) and
culturing the swab. Decolonization involves applying 2% mupirocin
ointment to the nostrils and using 4% chlorhexidine gluconate skin
wash (i.e., Hibiclens®).
SUMMARY
Methicillin-resistant staphylococcus aureus (MRSA) is a strain resistant
to many antibiotics. It can cause skin infections, respiratory infections,
sepsis, and infections in essentially any organ system. It is associated
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 20
with serious morbidities and high mortality rates. Fortunately, with
timely identification and proper treatment, MRSA-related infections can
be successfully treated and with good infection control the
transmission of MRSA can be significantly reduced. MRSA can produce
an infection in many different organs and organ systems. Vancomycin
has become the mainstay of antibiotic therapy for many types of MRSA
infections. The CDC recommends the use Standard Precautions to
prevent transmission of MRSA.
Please take time to help the NURSECE4LESS.COM course planners evaluate
nursing knowledge needs met following completion of this course by
completing the self-assessment Knowledge Questions after reading the
article. Correct Answers, page 23.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 21
1. Staphylococcus aureus bacterium is:
a. a gram-positive organism
b. is not part of the normal human flora
c. commonly found in the stomach
d. affecting approximately 5 % of the population
2. True or False. Methicillin-resistant Staphylococcus aureus
has been found in significant amounts on stethoscopes.
a. True
b. False
3. Transmission of MRSA is primarily through:
a. blood contact
b. sputum contact
c. skin contact
d. gastric secretions
4. Patients with community-acquired or hospital-acquired
MRSA pneumonia should be:
a. treated with IV or PO clindamycin
b. treated with linezolid
c. treated with IV vancomycin
d. all of the above
5. The CDC recommends the use Standard Precautions to:
a. prevent transmission of MRSA
b. include hand hygiene, gloving, mouth, nose and eye
protection
c. use of a gown when needed
d. all of the above
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 22
Correct Answers:
1. a
2. a
3. c
4. d
5. d
Footnote:
1. Lowy FD. Staphylococcal infections. In: Harrison’s Principles of Internal
Medicine. Online edition. Accessed October 25, 2012.
2. Parks NA, Croce MA. Routine screening for methicillin-resistant
Staphylococcus aureus. Surgical Infections. 2012;13:223-227.
3. Archer GL. Staphylococcus aureus: a well-armed pathogen. Clinical Infectious
Diseases. 1998;26:1179-1181.
4. Bowen ME, Craighead JD, Klanchar A. Multi-drug-resistant organisms in a
community living facility: Tracking patient interactions and time spent in
common areas. American Journal of Infection Control. 2012;40:677-679.
5. Archer GL. Staphylococcus aureus: a well-armed pathogen. Clinical Infectious
Diseases. 1998;26:1179-1181.
6. Ipppolito G, Leone s, Lauria FN, Nicastri E, Wenzel RP. Methicillin-resistant
Staphylococcus aureus: the superbug. International Journal of Infectious
Diseases. 2010;1454:S7-S11.
7. Fry DE, Barie PS. The changing face of Staphylococcus aureus: a continuing
surgical challenge. Surgical Infections. 2011;12:191-203.
8. Lowy FD. Staphylococcal infections. In: Harrison’s Principles of Internal
Medicine. Online edition. Accessed October 25, 2012.
9. Mediavilla JR, Chen L, Matthema B, Kreiswirth BN. Global epidemiology of
community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA).
Current Opinion in Microbiology. 2012;15:588-595.
10. Centers for Disease Control and Prevention. MRSA statistics. Accessed
October 31, 2012. Available at:
http://www.cdc.gov/mrsa/statistics/index.html.
11. Mediavilla JR, Chen L, Matthema B, Kreiswirth BN. Global epidemiology of
community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA).
Current Opinion in Microbiology. 2012;15:588-595.
12. Karampela I, Poulakou G, Dimopolous G. Community-acquired resistant
Staphylococcus aureus pneumonia: an update for the emergency and
intensive care physician. Minerva Anestesiologica. 2012;78:930-940.
13. DeLeo FR, Otto M, Kreiswirth BN, Chambers HF. Community-associated
methicillin-resistant Staphylococcus aureus. Lancet. 2010;375:1557-1568.
14. Lowy FD. Staphylococcal infections. In: Harrison’s Principles of Internal
Medicine. Online edition. Accessed October 25, 2012.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 23
15. Giannoudis PV, Townsend R, Homer-Vanniasinkam S, Wilcox MH. Soft tissue
and bone MRSA infections. Injury. 2011;42:S1-S2.
16. Kassavan DS, Pascarella L, Goldfarb MA. Surgical site infections: incidence
and trends at a community teaching hospital. American Journal of Surgery.
2011;201:749-753.
17. Gomes S, Altafi S, Garcia KM, et al. Occurrence of and risk factors for
methicillin-resistant Staphylococcus aureus at a Philadelphia teaching
hospital. American Journal of Infection Control. 2012;40:381-383.
18. Walraven C, Lingenfelter E, Rollo J, Madsen T, Alexander DP. Diagnostic and
therapeutic evaluation of community-acquired methicillin-resistant
Staphylococcus aureus (MRSA) skin and soft tissue infections in the
emergency department. Journal of Emergency Medicine. 2012;42:393-399.
19. Eseonu KC, Middleton SD, Eseonu CC. A retrospective study of risk factors
for poor outcomes in methicillin-resistant Staphylococcus aureus (MRSA)
infection in surgical patients. Journal of Orthopaedic Surgery & Research.
2011;23:25-30.
20. Walraven C, Lingenfelter E, Rollo J, Madsen T, Alexander DP. Diagnostic and
therapeutic evaluation of community-acquired methicillin-resistant
Staphylococcus aureus (MRSA) skin and soft tissue infections in the
emergency department. Journal of Emergency Medicine. 2012;42:393-399.
21. Lowy FD. Staphylococcal infections. In: Harrison’s Principles of Internal
Medicine. Online edition. Accessed October 25, 2012.
22. Jamal N, Teach SJ. Necrotizing fasciitis. Pediatric Emergency Care.
2011;27:1195-1199.
23. Sultan HY, Boyle AA, Sheppard N. Necrotising fasciitis. BMJ. 2012; 345:e4274
doi: 10.1136/bmj.e4274.
24. Jamal N, Teach SJ. Necrotizing fasciitis. Pediatric Emergency Care.
2011;27:1195-1199.
25. Jamal N, Teach SJ. Necrotizing fasciitis. Pediatric Emergency Care.
2011;27:1195-1199.
26. Sarani B, Strong M, Pascual J, Schwab CW. Necrotizing fasciitis: current
concepts and review of the literature. Journal of the American College of
Surgeons. 2009;208:279-288.
27. Edlich RF. Necrotizing fasciitis. eMedcine. October 14, 2011. Accessed
November 5, 2012.
28. Available at: http://emedicine.medscape.com/article/2051157overview#aw2aab6b2b4.
29. Chan JD, Pham TN, Wong J, et al. Clinical outcomes of linezolid vs
vancomycin in methicillin-resistant Staphylococcus aureus ventilatorassociated pneumonia: A retrospective analysis. Journal of Intensive Care
Medicine. 2011;26:385-391.
30. Kwong JC, Chua K, Charles PCP. Managing severe community-acquired
pneumonia due to community methicillin-resistant Staphylococcus aureus
(MRSA). Current Infectious Disease Reports. 2012;14:330-338.
31. Fangtham M, Baer AN. Methicillin-resistant Staphylococcus aureus arthritis in
adults: Case report and review of the literature. Seminars in Arthritis &
Rheumatism. 2012;41:604-610.
32. Dhanoa A, Singh VA, Mansor A, Yusof MY, Lim KT, Thong KL. Acute
haematogenous community-acquired methicillin-resistant Staphylococcus
aureus osteomyelitis in an adult: case report and review of the literature.
BMC Infectious Diseases. 2012;12:270-288.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 24
33. Lam SW, Bauer SR, Neuner EA. Predictors of septic shock in patients with
methicillin-resistant Staphylococcus aureus bacteremia. International Journal
of Infectious Diseases: 2012;16:e453-e456.
34. Lowy FD. Staphylococcal infections. In: Harrison’s Principles of Internal
Medicine. Online edition. Accessed October 25, 2012.
35. Pastagia M, Kleinman LC, Lacerda de la Cruz, EG, Jenkins SG. Predicting risk
for death from MRSA bacteremia. Emerging Infectious Diseases.
2012;18:1072-1080.
36. Miramonte C, Rinkle JA, Iden S, et al. The prevalence of methicillin-resistant
Staphylococcus aureus among out-of-hospital care providers and emergency
medical technician students. Prehospital Emergency Care. 2012;Oct 25;
[epub ahead of print].
37. Forster AJ, Oake N, Roth V, et al. Patient- level factors associated with
methicillin-resistant Staphylococcus aureus carriage at hospital admission: a
systematic review. American Journal of Infection Control. 2012; Sep 20:[epub
ahead of print].
38. Parks NA, Croce MA. Routine screening for methicillin-resistant
Staphylococcus aureus. Surgical Infections. 2012;13:223-227.
39. Parks NA, Croce MA. Routine screening for methicillin-resistant
Staphylococcus aureus. Surgical Infections. 2012;13:223-227.
40. Schroeder A, Schroeder MA, D’Amico F. What’s growing on your stethoscope?
Journal of Family Practice. 2009;58:404-409.
41. Williams C, Davis DL. Methicillin-resistant Staphylococcus aureus fomite
survival. Clinical Laboratory Science. 2009;22:34-38.
42. Ustun C, Cihangiroglu M. Healthcare workers mobile phones: A potential
cause of microbial cross-contamination between hospitals and community.
Journal of Occupational and Environmental Hygiene. 2012;9:538-542.
43. Tekerekğlu MS, Duman Y, Serindağ A, et al. Do mobile phones of patients,
companions, and visitors carry multi-drug-resistant hospital pathogens?
American Journal of Infection Control. 2011;39:379-381.
44. Kim JS, Kim HS, Park JY, et al. Contamination of x-ray cassettes with
methicillin-resistant Staphylococcus aureus and methicillin-resistant
haemolyticus in a radiology department. Annals of Laboratory Medicine.
2012;32:206-209.
45. Williams C, Davis DL. Methicillin-resistant Staphylococcus aureus fomite
survival. Clinical Laboratory Science. 2009;22:34-38.
46. McBryde ES, Bradley LC, Whitby M, McElwain DLS. An investigation of contact
transmission of methicillin-resistant Staphylococcus aureus. Journal of
Hospital Infection. 2004;58:104-108.
47. Faires MC, Pearl DL, Ciccotelli WA, et al. A prospective study to examine the
epidemiology of methicillin-resistant Staphylococcus aureus and Clostridium
dificile contamination in the general environment of three community
hospitals in southern Ontario, Canada. BMC Infectious Diseases. 2012;Nov
8:290 [epub ahead of print].
48. Liu C, Bayer A, Cosgrove SE, et al. Clinical practice guidelines by the
Infectious Diseases Society of America for the treatment of methicillinresistant Staphylococcus aureus infections in adults and children. Clinical
Infectious Diseases. 2011;52:1-38.
49. Kundrapu S, Sunkesula V, Jury LA, Sitzlar BM, Donskey CJ. Daily disinfection
of high-touch surfaces in isolation rooms to reduce contamination of
healthcare workers’ hands. Infection Control & Hospital Epidemiology.
2012;33:1039-1042.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 25
50. Gastmeier P, Schwab F, Chaberny I, Geffers C. Individual units rather than
the entire hospital as the basis of improvement: the example of two
methicillin-resistant Staphylococcus aureus cohort studies. Antimicrobial
Resistance & Infection Control. 2012;1:8-13.
51. Rebmann T, Aureden K. Preventing methicillin-resistant Staphylococcus
aureus transmission in hospitals: An executive summary of the Association for
Professionals in Infection Control and Epidemiology, Inc., Elimination Guide.
American Journal of Infection Control. 2011;39:595-598.
52. Centers for Disease Control & Prevention. Precautions to prevent the spread
of MRSA in healthcare settings. Accessed November 10, 2012.
53. Available at: http://www.cdc.gov/mrsa/prevent/healthcare/precautions.html.
54. Centers for Disease Control & Prevention. Precautions to prevent the spread
of MRSA in healthcare settings. Accessed November 10, 2012.
55. Available at: http://www.cdc.gov/mrsa/prevent/healthcare/precautions.html.
56. Creamer E, Galvin S, Dolan A, et al. Evaluation of screening risk and non-risk
patients for methicillin-resistant Staphylococcus aureus on admission in an
acute care hospital. American Journal of Infection Control. 2012;40:411-415.
57. Parks NA, Croce MA. Routine screening for methicillin-resistant
Staphylococcus aureus. Surgical Infections. 2012;13:223-227.
58. Creamer E, Galvin S, Dolan A, et al. Evaluation of screening risk and non-risk
patients for methicillin-resistant Staphylococcus aureus on admission in an
acute care hospital. American Journal of Infection Control. 2012;40:411-415.
59. Parks NA, Croce MA. Routine screening for methicillin-resistant
Staphylococcus aureus. Surgical Infections. 2012;13:223-227.
60. Kohler P, Bregenzer-Whitteck A, Rettenmund G, Otterbeach S, Schlegel S.
MRSA decolonization: success rate, risk factors for failure, and optimal
duration of follow-up. Infection. 2012;Jul 11:[epub ahead of print].
The information presented in this course is intended solely for the use of healthcare professionals taking
this course, for credit, from NurseCe4Less.com.
The information is designed to assist healthcare professionals, including nurses, in addressing issues
associated with healthcare.
The information provided in this course is general in nature, and is not designed to address any specific
situation. This publication in no way absolves facilities of their responsibility for the appropriate orientation
of healthcare professionals.
Hospitals or other organizations using this publication as a part of their own orientation processes should
review the contents of this publication to ensure accuracy and compliance before using this publication.
Hospitals and facilities that use this publication agree to defend and indemnify, and shall hold
NurseCe4Less.com, including its parent(s), subsidiaries, affiliates, officers/directors, and employees from
liability resulting from the use of this publication.
The contents of this publication may not be reproduced without written permission from
NurseCe4Less.com.
nursece4less.com nursece4less.com nursece4less.com nursece4less.com nursece4less.com 26