Vancomycin-resistant Staphylococcus aureus isolate from a patient in Pennsylvania.
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.
Tenover
Fred C
FC
Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. fnt1@cdc.gov
Weigel
Linda M
LM
Appelbaum
Peter C
PC
McDougal
Linda K
LK
Chaitram
Jasmine
J
McAllister
Sigrid
S
Clark
Nancye
N
Killgore
George
G
O'Hara
Caroline M
CM
Jevitt
Laura
L
Patel
Jean B
JB
Bozdogan
Bülent
B
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D015139:Blotting, Southern; D019729:Carbon-Oxygen Ligases / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000494:pharmacology; D010068:Oxacillin / Q000494:pharmacology; D010406:Penicillins / Q000494:pharmacology; D010414:Pennsylvania; D010957:Plasmids / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012293:Rifampin / Q000494:pharmacology; D013203:Staphylococcal Infections / Q000235:genetics / Q000382:microbiology*; D014640:Vancomycin / Q000494:pharmacology*; D020713:Vancomycin Resistance / Q000235:genetics*
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D010406:Penicillins; C071437:VanA ligase, Bacteria; D014640:Vancomycin; D015242:Ofloxacin; D019729:Carbon-Oxygen Ligases; D010068:Oxacillin; D012293:Rifampin