Failure of the BD GeneOhm StaphSR Assay for Direct Detection of Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus Isolates in Positive Blood Cultures Collected in the United States

Fifty-nine Staphylococcus aureus isolates from one hundred blood cultures containing gram-positive cocci in clusters were identified by conventional methods and the BD GeneOhm StaphSR assay (SR). The SR mis-identified three methicillin (meticillin)-resistant S. aureus (MRSA) isolates as methicillin-susceptible S. aureus (MSSA), while one MSSA isolate tested negative for S. aureus. The three MRSA isolates were strains with MREJ types that cannot be detected by the currently available SR.