ISSUE: The firm received increasing numbers of complaints for false negative MRSA results when compared to MRSA positive results received from culture methods. All Cepheid MRSA/SA Blood Culture Assay products have a potential of generating infrequent rates of false negative MRSA results, which could result in incorrect treatment or delay of care for patients with MRSA infection.
BACKGROUND: This test is used to detect methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus (SA) DNA directly from patient positive blood culture determined to be Gram Positive Cocci in Clusters (GPCC) or Gram Positive Cocci in singles (GPC) by Gram stain.
RECOMMENDATION: On July 1, 2010, the company issued a press release and sent its customers a revised Corrective Action Notice letter instructing them not to report the MRSA negative result when a MRSA negative/SA positive result is generated on the Cepheid MRSA/SA Blood Culture Assay. Instead, customers were instructed to conduct further antimicrobial susceptibility testing to determine the MRSA result. The MRSA positive/SA positive results generated on the Cepheid MRSA/SA Blood Culture Assay can still be reported.