Staphylococcus Methicillin-Resistant aureus
Shefali Aggarwal & Deepti D'Souza
Itinerary
Overview History Transmission Diagnosis Treatment Prevention Forecast
OVERVIEW
What is MRSA?
Staphylococcus aureus are gram positive bacteria MethicillinResistant S. aureus is a type of S. aureus that is resistant to multiple antimicrobial agents
Types of MRSA
CAMRSA Communityacquired MRSA HAMRSA Hospitalacquired MRSA
CA-MRSA
Mainly causes skin and soft tissue infections (SSTIs) Approx. 25% of CA MRSA patients require hospitalization CAMRSA strains are genetically diverse from HAMRSA strains
HA-MRSA
Acquired in the hospital setting Increased prevalence in immunocompromised and elderly patients Found to infect patients who have undergone invasive procedures
Pathophysiology
COLONIZATION Growth and multiplication of microbes in/on a host, without tissue invasion or damage INFECTION Entry and multiplication of microbes in a host via tissue invasion
Pathophysiology
COLONIZATION INFECTION Most commonly colonized Local or systemic area is anterior nare infections may occur in (external nostril) the tissues Other important sites for Conditions that may arise MRSA include skin, include SSTIs, wound perineum, open wounds, and surgical infections, and respiratory and bacteremia, and urinary tracts endocarditis
HISTORY
History
1880s S. aureus discovered Early 1940s Penicillin used as primary treatment Late 1940s & 1950s Resistance to penicillin observed 1961 First strain of MRSA identified 1968 First reported human case of MRSA NOW Resistance to entire class of betalactam antibiotics
betalactam ring
Penicilli n
TRANSMISSION
Transmission
Direct contact with an MRSA site on an infected individual Sharing of personal items previously in contact with infected sites Touching surfaces contaminated with MRSA
DIAGNOSIS
Diagnosis
Signs and Symptoms:
Red bump (possibly pus filled) Warm to touch Onsite pain Swollen, tender skin lesions Possible fever Little improvement after 23 days of antibiotic treatment
Manifestations of MRSA
SSTIs abscesses, furuncles (boils), cellulitis, and necrotizing fasciitis Pneumonia patients on ventilators and recently affected by influenza Osteomyelitis and Epidural Abscesses more common in adults; often require surgical intervention
Testing for MRSA
Swabs usually taken from nasal cavity or rectum Culture and sensitivity (C & S) tests conducted on samples Results returned in 23 days
TREATMENT
Treatment
Simple draining of abscess or boil may suffice for mild to moderate skin infections For severe skin infections, vancomycin is used intravenously
CA-MRSA Systemic Treatment
antibiotics not usually used If antibiotics needed, then prescribe
Trimethoprimsulfamethoxazole Clindamycin Doxycycline or minocycline
If patient has both MRSA and cellulitis, only clindamycin used
CA-MRSA Treatment
If patient is hospitalized, then prescribe
Vancomycin Linezolid Clindamycin Daptomycin
For necrotizing fasciitis, rapid surgical debridement used Clindamycin is the antibiotic for this treatment
HA-MRSA Treatment
Treatment for HAMRSA strains mainly involves the following 4 drugs:
Vancomycin Linezolid Clindamycin Daptomycin
Treatment of MRSA Carriers
Possible to be a carrier of MRSA and transmit it while not being infected yourself Decolonization: most common treatment available
Round 1: topical mupirocin (2x daily/ 5 days) Round 2: use Round 1 with antibiotics and/or antimicrobial soaps
Treatment of MRSA Carriers
Other treatments
Bathing with povidone iodine and nasal therapy with mupirocin for 3 days A type of combination therapy with mupirocin, chlorohexidine baths and oral antibiotics for 7 days
PREVENTION
Prevention
The best defense: practicing good hygiene
Good Hygiene Starts With...
Hand-washing...
Why wash your hands? Missed spots when washing hands
CA-MRSA Prevention
Simple steps for prevention in the community
Keeping cuts and scrapes clean Covering wounds with a bandage Avoiding contact with infected areas Shower promptly after exercising Avoiding sharing of personal items Washing soiled materials in hot water with bleach
Household Cleanliness
CLEANERS/ DETERGENTS Used to remove soi...