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Updated: Jun 11, 2026
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
Published on: February 9, 2011
Methicillin-resistant Staphylococcus aureus in wound cultures recovered from a combat support hospital in Iraq
Clinton K Murray1, Matthew E Griffith, Katrin Mende
1Infectious Disease Service, San Antonio Military Medical Center, Brooke Army Medical Center, Fort Sam Houston, Texas 78234, USA. Clinton.Murray@amedd.army.mil
Background:
Staphylococcus aureus infections complicate care of combat-related injuries and can independently result in skin and soft-tissue infections during deployments or training. Community-associated methicillin-resistant S. aureus (CA-MRSA) strains seem to produce severe disease but retain susceptibility to many oral antimicrobials. This study characterizes 84 MRSA isolates recovered from wound cultures at a combat support hospital in Iraq.
Methods:
MRSA strains recovered from December 2007 through March 2009 were analyzed. Antimicrobial resistance testing was determined by broth microdilution and the BD Phoenix Automated Microbiology System. The genotypic pattern was analyzed by pulsed-field gel electrophoresis and polymerase chain reaction identification of resistance and virulence genes.
Results:
No MRSA isolates from wound cultures were resistant to vancomycin. The most active oral antistaphylococcal agents were tetracycline (95% susceptibility), trimethoprim-sulfamethoxazole (94%), and clindamycin (94%). Of agents not typically recommended as monotherapy, 98% of isolates were susceptible to rifampin, 91% to moxifloxacin, and 60% to levofloxacin. The most common pulsed-field type (PFT) was USA300 (79%). The typical staphylococcal cassette chromosome mec IV elements carrying the CA-MRSA resistance genes were present in 88% of the isolates. Panton-Valentine leukocidin virulence genes were identified in 88% of isolates, including 100% of PFT USA300. The virulence gene associated with an arginine catabolic mobile element was present in 75% of isolates, including 94% of PFT USA300.
Conclusion:
This study is the first genotypic and phenotypic characterization of CA-MRSA recovered from wound cultures in a deployed combat hospital. The pattern noted was similar to that seen in soldiers stationed in the United States.
Insights
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) from combat wounds showed susceptibility to common oral antibiotics like tetracycline and trimethoprim-sulfamethoxazole. Most strains were USA300, carrying key virulence genes.
Area of Science:
- Infectious Diseases
- Microbiology
- Combat Medicine
Background:
- Staphylococcus aureus infections pose significant challenges in managing combat-related injuries.
- Community-associated methicillin-resistant S. aureus (CA-MRSA) strains can cause severe skin and soft-tissue infections.
- CA-MRSA strains often remain susceptible to various oral antimicrobial agents.
Purpose of the Study:
- To characterize the genotypic and phenotypic patterns of MRSA isolates from wound cultures in a deployed combat hospital.
- To assess the antimicrobial susceptibility of these CA-MRSA strains.
- To identify prevalent strains and associated virulence factors.
Main Methods:
- Analysis of 84 MRSA isolates from wound cultures collected between December 2007 and March 2009.
- Antimicrobial resistance testing using broth microdilution and the BD Phoenix Automated Microbiology System.
- Genotypic analysis via pulsed-field gel electrophoresis (PFGE) and PCR for resistance and virulence genes.
Main Results:
- No vancomycin resistance was observed in the MRSA isolates.
- High susceptibility rates to oral agents: tetracycline (95%), trimethoprim-sulfamethoxazole (94%), and clindamycin (94%).
- Prevalence of USA300 pulsed-field type (79%), with 88% carrying staphylococcal cassette chromosome mec IV elements and 88% harboring Panton-Valentine leukocidin genes.
Conclusions:
- This study provides the first genotypic and phenotypic characterization of CA-MRSA from combat wound cultures in a deployed setting.
- The observed CA-MRSA characteristics in deployed soldiers mirrored those found in the United States.
- Findings support the potential utility of specific oral antibiotics for treating CA-MRSA wound infections in deployed personnel.
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01:29Staphylococcal Skin Infections
01:25Clinical Significance of Antibiotic Resistance
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