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Updated: Jun 29, 2026
12:27
Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
Published on: January 3, 2020
Occurrence of a USA300 vancomycin-intermediate Staphylococcus aureus
Jeffrey C Hageman1, Jean Patel, Patrick Franklin
1Centers for Disease Control and Prevention, Atlanta, GA 30033, USA. jhageman@cdc.gov
Diagnostic Microbiology and Infectious Disease
|October 10, 2008
Summary
A vancomycin-intermediate Staphylococcus aureus (VISA) strain was identified in a patient with endocarditis. This finding suggests VISA infections may arise from community strains, not just hospital-acquired ones.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Staphylococcus aureus is a common cause of infections, including endocarditis.
- Vancomycin-intermediate Staphylococcus aureus (VISA) strains pose a significant treatment challenge.
- The emergence of VISA is typically associated with healthcare settings.
Observation:
- A VISA strain was isolated from the bloodstream of a patient with endocarditis.
- The isolate was identified as pulsed-field type USA300.
- The strain was also found to be nonsusceptible to daptomycin and carried Panton-Valentine leukocidin genes.
Findings:
- The VISA isolate belonged to the USA300 genetic background, commonly found in community-acquired infections.
- The strain exhibited resistance to both vancomycin and daptomycin.
- Presence of Panton-Valentine leukocidin genes indicates potential for increased virulence.
Implications:
- The VISA phenotype is not exclusive to hospital-associated Staphylococcus aureus strains.
- This case highlights the potential for VISA to emerge in community settings.
- Further research is needed to understand the mechanisms and epidemiology of VISA in community strains.
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