Methicillin-resistant Staphylococcus Aureus (MRSA) ICD9: 038.12 Melissa WilsonRN BSN FNP-S

Definition• Methicillin-resistant Staphylococcus Aureus (MRSA) is a type

of staph bacteria that is resistant to certain antibiotics called beta-lactams.

• These antibiotics include methicillin and other more common antibiotics such as oxacillin, penicillin, and amoxicillin.

• In the community, most MRSA infections are skin infections. • More severe or potentially life-threatening MRSA infections

occur most frequently among patients in healthcare settings.• While 25% to 30% of people are colonized* in the nose with

staph, less than 2% are colonized with MRSA.

(Gorwitz, 2008)

Defining Colonization• You can be "colonized" with MRSA, meaning that you carry

the bacteria on your skin or in your nose but you have no signs or symptoms of the illness.

• Staphylococcus aureus is a bacterium that lives normally on human skin surfaces – in fact 40% of us have the little guys all over us right now as we sit here in front of our computers.

• MRSA, which is simply an antibiotic resistant strain of Staphylococcus aureus, can also live on our skin for long periods or even permanently without us ever knowing it.

• This is called colonization, and depending on the population group/risk profile most studies show that 5-10% of us are carrying MRSA around with us wherever we go.

Up to date, 2013

Defining Colonization• As far as sites of colonization these bacteria can live on

virtually any skin surface, but they really love the warmest, dampest, darkest areas they can find including the nose, throat, armpits, and various sites “south of the border”.

• It is widely accepted in the medical community that the nose represents the primary reservoir of S. aureus/MRSA colonization in humans, with the throat emerging as another important area and all other sites considered secondary.

(Street, 2010)

Defining: HA-MRSA Versus CA-MRSA

Hospital Acquired MRSA (HA-MRSA) has a distinct difference from Community Acquired MRSA (CA-MRSA)

• Current evidence indicates that these CA-MRSA strains are genetically distinct from hospital-acquired MRSA (HA-MRSA), and that several unique community-acquired clones emerged simultaneously in different locations in the world (Vandenesch, 2003).

• CA-MRSA infections occur in otherwise healthy people without traditional risk factors

HA-MRSA versus CA-MRSA

• CA-MRSA cause a different spectrum of illness than HA-MRSA, and some CA-MRSA strains may be more virulent. CA-MRSA frequently causes skin and soft tissue infections (SSTI), however, CA-MRSA also can be associated with severe invasive disease (e.g., bacteremia/sepsis syndrome, pneumonia, pyomyositis, bone and joint infections, endocarditis, necrotizing fasciitis) (Naimi, 2003)

• Two genes are unique to CA-MRSA isolates and shared by isolates from three continents: a type IV SCCmec cassette and the PVL locus (Panton-Valentine leukocidin).

• CA-MRSA have different antibiotic susceptibility patterns from HA-MRSA; CA-MRSA are resistant to methicillin but generally are not multi-drug resistant. Many are sensitive to trimethoprim-sulfamethoxazole, clindamycin, aminoglycosides and quinolones.

(Naimi, 2003)

Pathophysiology• The organism may cause disease through tissue invasion and

toxin production.• The toxins liberated by the organism may have effects at sites

distant from the focus of infection or colonization. • The organism is then disseminated via hand carriage to body

sites where infection may occur (either through overt breaks in dermal surfaces, such as vascular catheterization or operative incisions, or through less evident breakdown in barrier function, such as eczema or shaving-associated micro-trauma).

NIH, 2008

Pathophysiology• Beta-lactam antibiotics inhibit the growth of sensitive bacteria by inactivating

enzymes located in the bacterial cell membrane, which are involved in the third stage of cell wall synthesis.

• It is during this stage that linear strands of peptidoglycan are cross-linked into a fishnet-like polymer that surrounds the bacterial cell and confers osmotic stability in the hypertonic milieu of the infected patient.

• Beta-lactams inhibit not just a single enzyme involved in cell wall synthesis, but a family of related enzymes (four to eight in different bacteria), each involved in different aspects of cell wall synthesis.

• These enzymes can be detected by their covalent binding of radioactively-labeled penicillin (or other beta-lactams) and hence have been called penicillin binding proteins (PBPs).

• Methicillin-resistant Staphylococcus is a virulent strain of S.aureus that disinhibits the effects of beta-lactams on this particular bacterium (National Institute of Health [NIH], 2008, p. 350-359).

Etiology•  Methicillin-resistant Staphylococcus aureus has resulted from

decades of prescribed antibiotics for treatment when unnecessary.

• For many years, prescriber’s have treated colds, flu and other viral infections with antibiotics that do not respond to these medications.

• Even when antibiotics are prescribed appropriately there is a contributory rise in drug-resistant bacteria because the antibiotics do not destroy all of the germs that the drug is targeting.

• Bacteria are evolutionary organisms that learn to survive treatment of one antibiotic and learn to resist others (“MayoClinic,” 2013).

Incidence• The most recent statistics find that the in 2011 there were

80,500 cases of infections in the United States as opposed to 111,300 in the year 2005.

• Overall the serious diagnosed cases in the hospitals dropped by 54% between the years 2005-2011.

• In the year 2005 there were 9.7 cases per 100,000 and in the year 2011 there were only 4.5 cases per 100,000.

• Incidence of individuals developing MRSA after being discharged from the hospital or being associated with a healthcare facility fell 28% during that same

Seaman, 2013

Incidence• In 2005 there were 21 infections per 100,000 and in 2011 there

reported cases were 15 per 100,000.• In the development of CA-MRSA the cases reported in 2011

were estimated at 16,560 and were an average of 5.32 patients per 100,000.

• It is difficult to track the number of CA-MRSA because many of the cases go unreported (http://www.cdc.gov/mrsa/tracking/index.html).

Seaman, 2013

Risk Factors HA-MRSA• Being hospitalized. MRSA remains a concern in hospitals,

where it can attack those most vulnerable — older adults and people with weakened immune systems.

• Having an invasive medical device. Medical tubing — such as intravenous lines or urinary catheters — can provide a pathway for MRSA to travel into your body.

• Residing in a long-term care facility. MRSA is prevalent in nursing homes. Carriers of MRSA have the ability to spread it, even if they're not sick themselves.

Mayo Clinic, 2013

Risk Factors CA-MRSA• Participating in contact sports. MRSA can spread easily

through cuts and abrasions and skin-to-skin contact.• Living in crowded or unsanitary conditions. Outbreaks of

MRSA have occurred in military training camps, child care centers and jails.

• Men having sex with men. Homosexual men have a higher risk of developing MRSA infections.

Mayo Clinic, 2013

Clinical Presentation• Depends on the site infected:• Skin: Swelling, erythema, pain, purulent drainage, pus, fever, inflammation,

necrosis, boils, bullae, furuncles, carbuncles, folliculitis and abscesses. Rash may appear as broken blood vessels under the skin.

• Joints: Redness, warmth, swelling, pain and fever, pain worse with movement, and inability to move the joint

• Lungs: Fever, cough, yellow/green/tan sputum, shortness or breath, painful breathing and pleuritic pain, N&V, weakness, fatigue, tachycardia, body aches, and rapid breathing.

• Heart: Anorexia, back pain, fever, excessive sweating at night, weight loss, rapid pulse, rash, headache, malaise and fever.

• Bone: Pain, tenderness, chills, fever, swelling, redness and bone tenderness. • Blood: Sepsis, anorexia, fever, muscle aches, fatigue, SOB, rapid

respirations and pulse, rash, confusion and coma.

Epocrates, 2013

Differential DiagnosesMRSA. The differential

diagnosis for MRSA are as follows: • Animal or human bites, • brain abscess, Cellulitis, • Decubitus Ulcer, • Diabetic Ulcer,• liver abscess, • myocardial abscess, • osteomyelitis, • Sepsis

• perianal abscess, • septic arthritis, • Pinal cord abscess, • streptococcus infections, • urinary tract infections and • wound infections• Pneumonia

MD Guidelines, 2013

Social/Environmental ConsiderationsHA-MRSA. • In the hospital, people who are infected or colonized with

MRSA often are placed in isolation as a precaution to prevent the spread of MRSA.

• Visitors and health care workers caring for people in isolation may be required to wear protective garments and must follow strict hand hygiene procedures.

• Contaminated surfaces and laundry items should be properly disinfected.

• Social isolation can have an impact on the patients self image.

CDC, 2013

Social/Environmental ConsiderationsCA-MRSA:• These community-associated MRSA (CA-MRSA) infections have been

identified in a variety of populations, including: athletes participating in close contact sports, military recruits in barracks settings, intravenous drug users, men who have sex with men, tattoo recipients, religious community members, and inmate populations.

• Moreover, many healthy adults and children—without any obvious risks for exposure—are also developing MRSA infections.

• In most communities in the U.S., MRSA is the leading cause of skin and soft tissue infections (SSTIs) among persons seeking emergency care ( BOP, 2012, p. 1).

Diagnostic Testing• The way to screen for MRSA is through cultures and biopsies

of the infected area. • If the patient develops a skin infection screening is done by

taking a culture of the infected area. • Suspicion of a respiratory infection or pneumonia a sputum

culture is obtained. • Often blood cultures are obtained when septicemia is suspected

and aseptic technique is used to obtain a urine culture. • Individuals who are at risk for developing MRSA or have a

history of MRSA are often screened prior to hospitalizations or surgical procedures.

Up to Date, 2013

Distinguishing between HA-MRSA and CA-MRSACA-MRSA can be distinguished from HA-MRSA by using the following criteria:• Diagnosis of MRSA is made in the outpatient setting or by a culture

positive for MRSA within 48 hrs. of hospital admission, AND • The patient has no past medical history of MRSA infection or

colonization, AND • The patient has no past medical history in the past 1 year of:

Hospitalization

Admission to a nursing home, skilled nursing facility, or hospice

Dialysis

Surgery

Permanent indwelling catheters or percutaneous medical devices

Naimi,2008

Management and Treatment Guidelines Non-pharmacological

• Keep your hands clean by washing thoroughly with soap and water or using an alcohol-based hand rub.

• Keep cuts and scrapes clean and covered with a bandage until healed, avoid contact with other people’s wounds or bandages, maintain a clean environment washing surfaces that come into contact with your skin and

• avoid sharing personal items such as towels or razors (CDC, 2013).

Management and Treatment Guidelines: Pharmacological HA-MRSA

• Hospitalized people with MRSA infections are usually treated with an intravenous medication.

• The intravenous antibiotic is usually continued until the person is improving.

• In many cases, the person will be given antibiotics after discharge from the hospital, either by mouth or by IV.

• This may be needed for a short period of time or for as long as six to eight weeks.

• Intravenous antibiotics can be given at home, by a visiting nurse, or in a rehabilitation facility.

• Nares may be swabbed with topical Mupirocin if patient is positive for MRSA in the nose.

CDC, 2013

Management Treatment guidelines Pharmacological CA-MRSA

• Treatment of MRSA at home usually includes a seven to 10 day course of an antibiotic (by mouth) such as trimethoprim-sulfamethoxazole (brand name: Bactrim), clindamycin, minocycline, or doxycycline.

• In addition to antibiotics, your healthcare provider may drain the infected area by inserting a needle or making a small cut in the skin.

• This is done to reduce the amount of infected material (pus), which will help the tissue to heal.

• In some cases additional strategies may be used for management of household spread and/or recurrent infection.

• These may include use of mupirocin ointment, chlorhexidine soap, and other techniques. These strategies are not always fully effective.

CDC, 2013

Complications• Defining MRSA complications is complex because it is

dependent on the system that it affects. • MRSA infections can resist the effects of many common

antibiotics, so they are more difficult to treat. • This can allow the infections to spread and sometimes become

life-threatening. • MRSA infections may affect your: bloodstream, lungs, heart,

bones and joints and potentially be fatal ("Mayo Clinic," 2013).

Complications

Necrotizing Fasciitis:

Skin swelling and redness• Skin discoloration • Skin may turn black• Skin blisters: May appear as

purple or blood*filled blisters• Severe skin pain• Muscle pain• Severe swelling beneath the

skin

• Drainage from the skin:• Red or brown fluid draining from

the skin• Pus draining from the skin

• Fever• Weakness and fatigue• Anorexia• Rapid pulse• Malaise

MD Guidelines, 2013

Necrotizing Fasciitis

Google Images, 2013

Follow up/Referrals• Follow up will be different dependent on how serious the

MRSA infection is. • Patients who are treated in the hospital may be sent home with

on IV antibiotics or oral antibiotics and will be followed up weekly.

• Follow up with Infectious Disease (ID) may be necessary. • Patients with CA-MRSA may be treated with topical

ointments, surgical incisions and oral antibiotics. These patients are followed up after 7-10 days.

• Surgical consult may be necessary for SSTI’s and non-healing wounds for debridement.

Education/Counseling• Contact your health care provider if you think you have an

infection so it can be treated quickly. Finding infections early and getting care will decrease the chance that the infection will become severe. • Signs of infection include redness, warmth, swelling, pus, and pain at

sites where your skin has sores, abrasions, or cuts. Sometimes these infections can be confused with spider bites.• Infections can also occur at sites covered by body hair or where uniforms

or equipment cause skin irritation or increased rubbing.

• Do not try to treat the infection yourself by picking or popping the sore.

CDC,2013

Education and Counseling• Cover possible infections with clean, dry bandages until you

can be seen by a doctor, nurse, or other health care provider such as an athletic trainer.

• Cover your wounds. Keep wounds covered with clean, dry bandages until healed. Follow your doctor’s instructions about proper care of the wound. Pus from infected wounds can contain MRSA so keeping the infection covered will help prevent the spread to others. Bandages and tape can be thrown away with the regular trash.  

CDC,2013

Education and Counseling• Clean your hands often. You, your family, and others in close

contact should wash their hands often with soap and water or use an alcohol-based hand rub, especially after changing the bandage or touching the infected wound.

• Do not share personal items. Personal items include towels, washcloths, razors, clothing, and uniforms.

• Wash used sheets, towels, and clothes with water and laundry detergent. Use a dryer to dry them completely.

• Wash clothes according to manufacturer’s instructions on the label.

CDC,2013

Questions.

1. MRSA describes a specific type of bacteria that are resistant to certain antibiotics. True or False

2. Is MRSA contagious? Yes or No

3. A commonly used word to describe MRSA is...

a) Superbug

b) E coli

c) Salmonella

d) Rash

MRSA Infection,2013

Questions4. MRSA bacteria are most likely found...

a) The community

b) The hospital

5) Some of us carry MRSA bacteria in our...

a) Mouths

b) Noses

c) Eyes

d) Throats

6) What is the best defense against MRSA?

a) Good hygiene

b) Vaccines

c) Avoiding antibiotics

d) All the above

MRSA Infection,2013

Questions7). MRSA most often enters the body through droplets from coughing or sneezing. True or False

8). MRSA can cause sepsis, which is an infection of the blood. True or False.

9). A MRSA skin infection can often mimic a ________________.

a) cut

b) Scrape

c) Spider bite

d) Stye

10). MRSA infections can cause complications such as...

a) “flesh eating” disease

b) Pneumonia

c) Death

d) All of the above

MRSA Infection,2013

References• Anthony Harris. (2013). Patient Information:Methicillin-resistant Staphylococcus aureus (MRSA)

(Beyond the Basics). Retrieved from http://www.uptodate.com/contents/methicillin-resistant-staphylococcus-aureus-mrsa-beyond-the-basics

• Epocrates Online. (2013). MRSA. Retrieved from https://online.epocrates.com/u/2924910/MRSA/Basics/Etiology

• Evans, R. P. (2008). The Silent Epidemic:CA-MRSA and HA-MRSA. Retrieved from http://www.aaos.org/news/aaosnow/may08/research1.asp

• Federal Bureau of Prisons Clinical Practice Guidelines. (2012). Management of Methicillin-Resistant Staphylococcus aureus (MRSA) Infections. Retrieved from http://www.bop.gov/news/PDFs/mrsa.pdf

• MD Guidelines. (2013). Methicillin Resistant Staphylococcus Aureus (MRSA). Retrieved from http://www.mdguidelines.com/methicillin-resistant-staphylococcus-aureus-mrsa

• MRSA. (2013). Retrieved from https://online.epocrates.com/u/2924910/MRSA/Basics/Etiology• MRSA Infection. (2013). Retrieved 10/22/2013, from

http://www.mayoclinic.org/mrsa/causes.html• MRSA infection. (2013). Retrieved from http://www.mayoclinic.org/mrsa/complications.html• Mandal, A. (2013). What is Staphylococcus Aureus? Retrieved October 28, 2013, from

http://www.news-medical.net/health/What-is-Staphylococcus-Aureus.aspx• Mayo Clinic. (2013). MRSA Infection. Retrieved from http://www.mayoclinic.org/mrsa/• Methicillin Resistant Staphylococcus Aureus (MRSA). (2009). Retrieved from

http://www.mdguidelines.com/

References• Methicillin-resistant Staphylococcus Aureus (MRSA) Infections. (2013). Retrieved from

http://www.cdc.gov/mrsa/• Methicillin-resistant Staphylococcus Aureus (MRSA) Infections:Diagnosiing and Testing MRSA

Infections. (2013). Retrieved from http://www.cdc.gov/mrsa/lab/index.html• Naimi, T. S., LeDell, K. H., & Cosmo-Sabetti, K. (2010). Comparison of community- and health care-

associated methicillin-resistant Staphylococcus aureus infection. JAMA., 10;290(22)(), 2976-84. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/14665659

• National Institute of Health. (2008, July 16,2008). Pathogenesis of Methicillin-resistant Staphylococcus Aureus Infection. United States National Library of Health. http://dx.doi.org/10.1086/533591

• Seaman, A. M. (2013). Hospital-acquired MRSA Infection Rates Falling: CDC. Retrieved from http://www.reuters.com/article/2013/09/16/us-hospital-mrsa-idUSBRE98F0X920130916

• The Infectious Diseases Society of America. (2011, January 4, 2011). Clinical Practice Guidelines by the Infectious Diseases Society of America for the Treatment of Methicillin-resistant Staphylococcus Aureus Infections in Adults and Children. IDSA Guidelines, 1-38. http://dx.doi.org/DOI: 10.1093/cid/ciq146

• Understanding MRSA; Diagnosis and Treatment. (2013). Retrieved October 23, 2013, from http://www.webmd.com/skin-problems-and-treatments/understanding-mrsa-detection-treatment

• Vandenesch, F., Naimi, T., & Enright, M. (2003). Community-acquired Methicillin Resistant Staphylococcus aureus Carrying Panton-Valenitine Leukocidin Genes:World wide emergence. Emergency Infectious Disease, 9(), 978-984.

• and Antibiotic Resistance by Bacteria . Retrieved from http://www.emedicinehealth.com/ndm-1/article_em.htm