title: Characterization of a widespread strain of methicillin-susceptible Staphylococcus aureus associated with nosocomial infections.
abstract: Thirty Staphylococcus aureus isolates from five hospitals were determined to exhibit borderline susceptibility to the antistaphylococcal penicillins. Of the isolates submitted for phage typing, 96% belonged to phage group 94/96, and 96% possessed a common plasmid, pBW15. Also, four reference borderline-susceptible isolates from the Centers for Disease Control belonged to phage group 94/96 and possessed pBW15. Screening of 43 other phage group 94/96 isolates demonstrated that 36 (84%) contained pBW15 and exhibited the borderline phenotype. In contrast, pBW15 was not identified among 10 penicillin-susceptible, 10 methicillin-resistant, and 40 penicillin-resistant but non-borderline-susceptible S. aureus. These data show a close association between pBW15, phage group 94/96, and the borderline-susceptible phenotype. Furthermore, these isolates were associated with infections in multiple institutions, suggesting the widespread dissemination of a clinically important and pathogenic strain of S. aureus.
authors.affiliation: Department of Pathology, Vanderbilt University School of Medicine, Nashville, Tennessee.
authors.forename: L W
authors.initials: LW
authors.lastname: McMurray
authors.forename: D S
authors.initials: DS
authors.lastname: Kernodle
authors.forename: N L
authors.initials: NL
authors.lastname: Barg
mesh_terms: D001434:Bacteriophage Typing; D003428:Cross Infection / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis; D006801:Humans; D008712:Methicillin / Q000494:pharmacology; D010068:Oxacillin / Q000494:pharmacology; D010400:Penicillin G / Q000494:pharmacology; D010403:Penicillin Resistance; D010641:Phenotype; D010957:Plasmids; D015183:Restriction Mapping; D013203:Staphylococcal Infections / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000145:classification* / Q000187:drug effects / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D010400:Penicillin G; D008712:Methicillin; D010068:Oxacillin