The performance of the BD geneOhm MRSA™ assay for MRSA isolated from clinical patients in Japan, including the effects of specimen contamination and ways to improve it

J Infect Chemother. 2011 Apr;17(2):214-8. doi: 10.1007/s10156-010-0104-2. Epub 2010 Aug 17.

Abstract

The BD geneOhm MRSA™ assay has been increasingly used in recent years, and it is possible to use it to screen and detect methicillin-resistant Staphylococcus aureus (MRSA) from a specimen within 2 h. The purpose of the present study was to evaluate the performance, i.e., the specificity and sensitivity, of the BD geneOhm MRSA™ assay to detect MRSA. Its specificity was assessed to be 100% compared to bacterial culture methods, which are commonly used in medical laboratories. Its bacterial limit of detection was over 10 colony-forming units (cfu) per reaction, although MRSA was detected at a cfu below 10 per reaction in a few samples. Additionally, the effect of MRSA isolate contamination was examined. While contamination with protein or other bacteria did not affect the outcome, contamination with a high concentration of blood resulted in an unresolved outcome. To inactivate polymerase chain reaction (PCR) inhibitors, the DNA samples were freeze-thawed prior to the BD geneOhm MRSA™ assay, which led to the sensitivity of the assay increasing. In summary, the BD geneOhm MRSA™ assay is rapid and shows high specificity and sensitivity of cultured MRSA isolates. It will, therefore, be a valuable diagnostic tool for detecting MRSA in specimens from clinical patients.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Culture Media
  • DNA, Bacterial / analysis
  • DNA, Bacterial / genetics
  • DNA, Bacterial / isolation & purification
  • Drug Contamination
  • Humans
  • Japan
  • Methicillin-Resistant Staphylococcus aureus / genetics
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Molecular Diagnostic Techniques / methods*
  • Polymerase Chain Reaction / methods*
  • Reagent Kits, Diagnostic
  • Sensitivity and Specificity
  • Staphylococcal Infections / diagnosis*
  • Staphylococcal Infections / microbiology

Substances

  • Culture Media
  • DNA, Bacterial
  • Reagent Kits, Diagnostic