Continuing Medical EducationCommunity-acquired methicillin-resistant Staphylococcus aureus
Section snippets
Key points
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Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) has existed for more than a decade but recently has emerged as an important worldwide pathogen.
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Genes for resistance are typically carried by staphylococcal chromosomal cassette mec type IVa.
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This small gene cassette codes only for methicillin resistance (rather than multiple antibiotic resistance).
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Clones with multiple antibiotic resistance are emerging in Asia.
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Outbreaks in the United States occur in both rural and urban
Key points
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Community-acquired MRSA clones are genetically distinct from classic health care–associated clones.
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Community-acquired MRSA has now crossed over from the community into health care settings.
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It may be best to refer to “community-type strains” and “health care–type strains,” regardless of where the infection is actually acquired.
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In the hospital setting, community-acquired MRSA tends to produce cutaneous and joint infections, just as it does in the community.
The distinction between
Key points
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Outcomes for hospitalized patients with MRSA are worse than for those with methicillin-sensitive Staphylococcus aureus (MSSA).
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Community-acquired MRSA colonization is much more likely to progress to clinical infection than is MSSA colonization.
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The resulting community-acquired MRSA infection is likely to be a cutaneous abscess or folliculitis.
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Panton-Valentine leukocidin is the major virulence factor among community-acquired MRSA strains.
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The community-acquired MRSA pulmonary syndrome is a distinct
Key points
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The primary treatment for a community-acquired MRSA abscess is drainage (Fig 1).
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Many patients have responsed to drainage alone.
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Failure to drain the abscess may have catastrophic consequences, even if an effective antibiotic is prescribed.
Population-based surveillance data from Baltimore and Atlanta and hospital laboratory–based sentinel surveillance of 12 hospitals in Minnesota between 2001 and 2002 included 1,647 cases of community-acquired MRSA infection, representing between 8% and 20% of
Key points
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Surgical drainage, rather than antibiotic therapy, is the single most important intervention for a community-acquired MRSA abscess.
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When an antibiotic is required, trimethoprim-sulfamethoxazole remains an inexpensive and effective choice for the majority of patients.
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Tetracyclines are effective for many strains.
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Overall, inducible lincosamide resistance is becoming more prevalent, although a reverse trend has been noted in one Dallas hospital.
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Although many community-acquired MRSA strains remain
Key points
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Community-acquired MRSA skin infections recur at a high rate.
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Skin surface and fomite colonization appear to be at least as important as nasal colonization.
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Alcohol-based disinfectants may be superior to detergent-based formulations.
Recurrence of community-acquired MRSA infections is related to untreated colonization. Close contacts of those with MRSA infection often become colonized or infected. Both nasal and skin surface colonization must be addressed to reduce the risk to the patient and
Key points
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Seriously ill patients should be hospitalized.
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Most infections in clinically well patients are appropriately treated on an outpatient basis with oral antibiotics.
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Pus-containing lesions, especially in recognized risk groups, suggest community-acquired MRSA infection.
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The primary treatment for an abscess remains drainage.
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Sulfa drugs are an appropriate choice for most community-acquired MRSA infections that require antibiotic therapy.
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The first-line empiric therapy for most other skin infections
Conclusions
Community-acquired MRSA strains are increasing in prevalence and can be highly virulent. Most infections present as skin and soft-tissue abscesses, which may respond to drainage alone. A severe syndrome of lung and septic joint involvement often affects children and may be fatal.
Sulfa drugs represent the most valuable class of antibiotics for the treatment of cutaneous community-acquired MRSA infections. Tetracyclines and clindamycin have also been used successfully, although concerns about
References (133)
- et al.
Are all community methicillin-resistant Staphylococcus aureus related? A comparison of their mec regions
Pathology
(2003) - et al.
Epidemiology of capsular and surface polysaccharide in Staphylococcus aureus infections complicated by bacteraemia
J Hosp Infect
(2005) - et al.
Genetic analysis of community isolates of methicillin-resistant Staphylococcus aureus in Western Australia
J Hosp Infect
(1993) - et al.
Community-acquired methicillin-resistant Staphylococcus aureus skin infection: a retrospective analysis of clinical presentation and treatment of a local outbreak
J Am Acad Dermatol
(2004) - et al.
High prevalence of methicillin-resistant Staphylococcus aureus in emergency department skin and soft tissue infections
Ann Emerg Med
(2005) - et al.
Genome and virulence determinants of high virulence community-acquired MRSA
Lancet
(2002) - et al.
Emergence of community-associated methicillin-resistant Staphylococcus aureus USA 300 clone as a cause of health care–associated infections among patients with prosthetic joint infections
Am J Infect Control
(2005) - et al.
Three-year survey of community-acquired methicillin-resistant Staphylococcus aureus producing Panton-Valentine leukocidin in a French university hospital
J Hosp Infect
(2005) - et al.
Bilateral blindness from orbital cellulitis caused by community-acquired methicillin-resistant Staphylococcus aureus
Am J Ophthalmol
(2005) Efficacy of current agents used in the treatment of Gram-positive infections and the consequences of resistance
Clin Microbiol Infect
(2005)
Ciprofloxacin and levofloxacin resistance among methicillin-sensitive Staphylococcus aureus isolates from keratitis and conjunctivitis
Am J Ophthalmol
Detection of mutations in quinolone resistance-determining regions in levofloxacin- and methicillin-resistant Staphylococcus aureus: effects of the mutations on fluoroquinolone MICs
Diagn Microbiol Infect Dis
Methicillin-resistant Staphylococcus aureus: clinical manifestations and antimicrobial therapy
Clin Microbiol Infect
Nosocomial infections due to methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci at a university hospital in Taiwan from 1991 to 2003: resistance trends, antibiotic usage and in vitro activities of newer antimicrobial agents
Int J Antimicrob Agents
In vitro activity of linezolid, synercid and telithromycin against genetically defined high level fluoroquinolone-resistant methicillin-resistant Staphylococcus aureus
Int J Antimicrob Agents
Dicationic dithiocarbamate carbapenems with anti-MRSA activity
Bioorg Med Chem
Study of the synergism between carbapenems and vancomycin or teicoplanin against MRSA, focusing on S-4661, a carbapenem newly developed in Japan
J Infect Chemother
Evolutionary models of the emergence of methicillin-resistant Staphylococcus aureus
Antimicrob Agents Chemother
Bloodstream Infection Study Group of the Relais d'Hygiene du Centre. Epidemiology and typing of Staphylococcus aureus strains isolated from bloodstream infections
J Clin Microbiol
Outbreaks of community-associated methicillin-resistant Staphylococcus aureus skin infections—Los Angeles County, California, 2002–2003
MMWR Mor Mortal Wkly Rep
Epidemiology, treatment, and prevention of community-acquired methicillin-resistant Staphylococcus aureus infections
Mayo Clin Proc
Widespread skin and soft-tissue infections due to two methicillin-resistant Staphylococcus aureus strains harboring the genes for Panton-Valentine leucocidin
J Clin Microbiol
Comparison of community- and health care–associated methicillin-resistant Staphylococcus aureus infection
JAMA
Community-acquired methicillin-resistant Staphylococcus aureus, a new player in sports medicine
Curr Sports Med Rep
Community-associated methicillin-resistant Staphylococcus aureus
Clin Infect Dis
Origins of community strains of methicillin-resistant Staphylococcus aureus
Clin Infect Dis
Cutaneous community-acquired methicillin-resistant Staphylococcus aureus infection in participants of athletic activities
South Med J
Incidence of and risk factors for clinically significant methicillin-resistant Staphylococcus aureus infection in a cohort of HIV-infected adults
J Acquir Immune Defic Syndr
Risk factors and predictors of mortality of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia in HIV-infected patients
J Antimicrob Chemother
Population dynamics of nasal strains of methicillin-resistant Staphylococcus aureus—and their relation to community-associated disease activity
J Infect Dis
Perdreau-Remington F. Community-adapted methicillin-resistant Staphylococcus aureus (MRSA): population dynamics of an expanding community reservoir of MRSA
J Infect Dis
Emergence of community-associated methicillin-resistant Staphylococcus aureus at a Memphis, Tennessee, Children's Hospital
Pediatr Infect Dis J
Epidemic of community-acquired methicillin-resistant Staphylococcus aureus infections: a 14-year study at Driscoll Children's Hospital
Arch Pediatr Adolesc Med
Emergence and spread of community-associated methicillin-resistant Staphylococcus aureus in rural Wisconsin, 1989 to 1999
J Clin Microbiol
An outbreak of community-onset methicillin-resistant Staphylococcus aureus skin infections in southwestern Alaska
Infect Control Hosp Epidemiol
Community-acquired methicillin-resistant Staphylococcus aureus in southern New England children
Pediatrics
Community-acquired methicillin-resistant Staphylococcus aureus: an emerging pathogen
Infect Control Hosp Epidemiol
Geographic information system localization of community-acquired MRSA soft tissue abscesses
J Pediatr Surg
Characterization of methicillin-resistant Staphylococcus aureus isolated from retail raw chicken meat in Japan
J Vet Med Sci
Hospital transmission of community-acquired methicillin-resistant Staphylococcus aureus among postpartum women
Clin Infect Dis
Transmission of methicillin-resistant Staphylococcus aureus in the neonatal intensive care unit from a patient with community-acquired disease
Infect Control Hosp Epidemiol
Community-acquired methicillin-resistant Staphylococcus aureus: a meta-analysis of prevalence and risk factors
Clin Infect Dis
Nasal carriage of methicillin-resistant Staphylococcus aureus in school children without identifiable risk factors in northern Taiwan
Pediatr Infect Dis J
Prevalence of and risk factors for colonization with methicillin-resistant Staphylococcus aureus at the time of hospital admission
Infect Control Hosp Epidemiol
Healthcare-associated Staphylococcus aureus bacteremia and the risk for methicillin resistance: is the Centers for Disease Control and Prevention definition for community-acquired bacteremia still appropriate?
Infect Control Hosp Epidemiol
Costs and outcomes among hemodialysis-dependent patients with methicillin-resistant or methicillin-susceptible Staphylococcus aureus bacteremia
Infect Control Hosp Epidemiol
Spread of methicillin-resistant Staphylococcus aureus (MRSA) among household contacts of individuals with nosocomially acquired MRSA
Infect Control Hosp Epidemiol
Natural history of community-acquired methicillin-resistant Staphylococcus aureus colonization and infection in soldiers
Clin Infect Dis
Clinical presentation of community-acquired methicillin-resistant Staphylococcus aureus in pregnancy
Obstet Gynecol
Necrotizing fasciitis caused by community-associated methicillin-resistant Staphylococcus aureus in Los Angeles
N Engl J Med
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2021, European Journal of Pharmaceutical SciencesCitation Excerpt :Thus, its occurrence has been associated with health care settings, including hospitals and other health care environments (Kale and Dhawan, 2016). Moreover, this pathogen has been emerged as a major cause of community-associated infections, as well (Elston, 2007). MRSA strains are instantly classified as a multidrug resistant strains called „superbugs“.
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Funding sources: None.
Disclosure: The author has been a consultant and speaker for Abbott Laboratories and Medicis. His work for them involved a cephalosporin inactive against methicillin-resistant Staphylococcus aureus.
Reprints not available from the author.