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Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
12:27

Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes

Published on: January 3, 2020

Post-influenza pneumonia caused by the USA300 community-associated methicillin-resistant Staphylococcus aureus in

Kyung Mok Sohn1, Doo Ryeon Chung, Jin Yang Baek

  • 1Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.

Journal of Korean Medical Science
|March 2, 2012
PubMed

Insights

The USA300 community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strain caused pneumonia in Korea. This marks the first reported case of USA300 pneumonia following pandemic influenza A (H1N1).

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Public Health

Background:

  • The USA300 clone is a successful community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strain prevalent in North America.
  • PVL-negative ST72-CA-MRSA has been predominant in Korea, with limited reports of USA300 infections.

Observation:

  • A 50-year-old man in Korea developed pneumonia after influenza A (H1N1) infection.
  • The patient required ventilator support due to respiratory failure.

Findings:

  • Sputum and endotracheal aspirate cultures identified MRSA.
  • Molecular typing confirmed the isolate as PVL-positive, ST 8-MRSA-SCCmec type IV, matching the USA300 strain.
  • Pulsed-field gel electrophoresis (PFGE) patterns confirmed the isolate's identity as USA300.

Implications:

  • This case highlights the emergence of the USA300 CA-MRSA strain in Korea, causing pneumonia post-influenza A (H1N1).
  • It underscores the need for enhanced surveillance of CA-MRSA infections, particularly in the context of viral respiratory infections.
Keywords:
Influenza, HumanMethicillin-Resistant Staphylococcus aureusPneumonia

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