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Updated: Jul 14, 2026
09:03
Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
Published on: September 5, 2013
Intermediate vancomycin susceptibility in a community-associated MRSA clone.
Christopher J Graber1, Margaret K Wong, Heather A Carleton
1Division of Infectious Diseases, University of California, San Francisco General Hospital, 94110, USA. christopher.graber@ucsf.edu
Emerging Infectious Diseases
|June 8, 2007
Summary
A USA300 community-associated methicillin-resistant Staphylococcus aureus (MRSA) strain showed treatment failure due to intermediate vancomycin susceptibility. This MRSA strain also had reduced daptomycin susceptibility, complicating osteomyelitis treatment.
Area of Science:
- Infectious Diseases
- Microbiology
- Clinical Medicine
Background:
- Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) USA300 is a prevalent pathogen.
- Osteomyelitis requires effective antibiotic treatment.
- Catheter-associated septic thrombophlebitis can lead to serious infections.
Observation:
- A 56-year-old male patient with lumbar osteomyelitis experienced treatment failure.
- The patient received a 6-week course of vancomycin for catheter-associated septic thrombophlebitis.
- The causative MRSA strain exhibited intermediate vancomycin susceptibility and reduced daptomycin susceptibility.
Findings:
- The MRSA strain demonstrated reduced susceptibility to vancomycin and daptomycin.
- Treatment failure occurred despite vancomycin therapy.
- The bone infection was caused by this specific MRSA strain.
Implications:
- Emerging antibiotic resistance in MRSA poses a significant clinical challenge.
- Vancomycin and daptomycin may be less effective against certain MRSA strains.
- Alternative treatment strategies are needed for osteomyelitis caused by resistant MRSA.
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