Vancomycin-resistant Staphylococcus aureus isolate from a patient in Pennsylvania

Antimicrob Agents Chemother. 2004 Jan;48(1):275-80. doi: 10.1128/AAC.48.1.275-280.2004.

Abstract

A vancomycin-resistant Staphylococcus aureus (VRSA) isolate was obtained from a patient in Pennsylvania in September 2002. Species identification was confirmed by standard biochemical tests and analysis of 16S ribosomal DNA, gyrA, and gyrB sequences; all of the results were consistent with the S. aureus identification. The MICs of a variety of antimicrobial agents were determined by broth microdilution and macrodilution methods following National Committee for Clinical Laboratory Standards (NCCLS) guidelines. The isolate was resistant to vancomycin (MIC = 32 micro g/ml), aminoglycosides, beta-lactams, fluoroquinolones, macrolides, and tetracycline, but it was susceptible to linezolid, minocycline, quinupristin-dalfopristin, rifampin, teicoplanin, and trimethoprim-sulfamethoxazole. The isolate, which was originally detected by using disk diffusion and a vancomycin agar screen plate, was vancomycin susceptible by automated susceptibility testing methods. Pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA indicated that the isolate belonged to the USA100 lineage (also known as the New York/Japan clone), the most common staphylococcal PFGE type found in hospitals in the United States. The VRSA isolate contained two plasmids of 120 and 4 kb and was positive for mecA and vanA by PCR amplification. The vanA sequence was identical to the vanA sequence present in Tn1546. A DNA probe for vanA hybridized to the 120-kb plasmid. This is the second VRSA isolate reported in the United States.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Anti-Infective Agents / pharmacology
  • Bacterial Proteins / genetics
  • Blotting, Southern
  • Carbon-Oxygen Ligases / genetics
  • DNA, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial
  • Microbial Sensitivity Tests
  • Ofloxacin / pharmacology
  • Oxacillin / pharmacology
  • Penicillins / pharmacology
  • Pennsylvania
  • Plasmids / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Rifampin / pharmacology
  • Staphylococcal Infections / genetics
  • Staphylococcal Infections / microbiology*
  • Vancomycin / pharmacology*
  • Vancomycin Resistance / genetics*

Substances

  • Anti-Bacterial Agents
  • Anti-Infective Agents
  • Bacterial Proteins
  • DNA, Bacterial
  • Penicillins
  • VanA ligase, Bacteria
  • Vancomycin
  • Ofloxacin
  • Carbon-Oxygen Ligases
  • Oxacillin
  • Rifampin