Emergence of community-acquired meticillin-resistant Staphylococcus aureus strain USA300 as a cause of necrotising community-onset pneumonia

Lancet Infect Dis. 2009 Jun;9(6):384-92. doi: 10.1016/S1473-3099(09)70133-1.


Meticillin-resistant Staphylococcus aureus (MRSA), usually known as a nosocomial pathogen, has emerged as the predominant cause of skin and soft-tissue infections in many communities. Concurrent with the emergence of community-acquired MRSA (CA-MRSA), there have been increasing numbers of reports of community-acquired necrotising pneumonia in young patients and others without the classic health-care-associated risk factors. Community-onset necrotising pneumonia due to CA-MRSA is now recognised as an emerging clinical entity with distinctive clinical features and substantial morbidity and mortality. A viral prodrome (eg, influenza or influenza-like illness) followed by acute onset of shortness of breath, sepsis, and haemoptysis is the most frequent clinical presentation. The best treatment of this partly toxin-mediated disease has not been clearly defined. Whereas cases of CA-MRSA pneumonia have now been reported from almost every continent, the overall burden of disease of this emerging syndrome remains incompletely described. We report two related cases of community-onset pneumonia due to the MRSA USA300 genotype and review the literature regarding the emergence of CA-MRSA pneumonia.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Adult
  • Anti-Bacterial Agents / therapeutic use
  • Bacterial Proteins / genetics
  • Bacterial Toxins / genetics
  • Clindamycin / therapeutic use
  • Communicable Diseases, Emerging / drug therapy
  • Communicable Diseases, Emerging / microbiology*
  • Communicable Diseases, Emerging / physiopathology
  • Community-Acquired Infections / drug therapy
  • Community-Acquired Infections / microbiology
  • Community-Acquired Infections / physiopathology
  • Drug Resistance, Multiple, Bacterial / genetics
  • Exotoxins / genetics
  • Female
  • Genotype
  • Humans
  • Intubation, Intratracheal
  • Leukocidins / genetics
  • Male
  • Methicillin-Resistant Staphylococcus aureus / genetics
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Middle Aged
  • Penicillin-Binding Proteins
  • Pneumonia, Staphylococcal / drug therapy
  • Pneumonia, Staphylococcal / microbiology*
  • Pneumonia, Staphylococcal / physiopathology
  • United States
  • Virulence Factors


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Bacterial Toxins
  • Exotoxins
  • Leukocidins
  • Panton-Valentine leukocidin
  • Penicillin-Binding Proteins
  • Virulence Factors
  • mecA protein, Staphylococcus aureus
  • Clindamycin