MRSA detection: comparison of two molecular methods (BD GeneOhm® PCR assay and Easy-Plex) with two selective MRSA agars (MRSA-ID and Oxoid MRSA) for nasal swabs

  • S. J. van HalEmail author
  • Z. Jennings
  • D. Stark
  • D. Marriott
  • J. Harkness


Screening of patients is an important component for methicillin-resistant Staphylococcus aureus (MRSA) containment. The aim of this study was to determine the utility of molecular methods compared to selective agars for MRSA detection. Consecutive high risk patients (n = 200) were screened for nasal MRSA colonization using chromogenic selective agars (MRSA ID and CMRSA) as well as the BD GeneOhm MRSA (previously known as IDI-MRSA) and the Easy-Plex commercial real time PCR assays. The sensitivities of the molecular methods were similar to the BD GeneOhm MRSA (86%) and Easy-Plex (84%). The chromogenic agars, MRSA ID and CMRSA, showed sensitivities of 62% and 84%, respectively. Sensitivity was influenced by both the MRSA antibiograms and MRSA clonal type. The specificity was >98% in all methods except for the Easy-Plex assay (90%). Sensitivity of selective agars increased with 48 hours of incubation with a corresponding decrease in specificity. In conclusion, molecular detection methods for MRSA remain sensitive and rapid but are associated with greater expense.


Selective Agar Nasal Swab mecA Gene Selective Agar Plate Infection Control Resource 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank Thelma Barbagiannakos and A/Professor Ian Gosbell for the MRSA typing.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • S. J. van Hal
    • 1
    Email author
  • Z. Jennings
    • 1
  • D. Stark
    • 1
  • D. Marriott
    • 1
  • J. Harkness
    • 1
  1. 1.Department of Microbiology and Infectious DiseasesSt.Vincent’s HospitalDarlinghurstAustralia

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