BD Diagnostics has received FDA clearance to market the BD MAX MRSA XT Assay for use on the fully-automated BD MAX System. This is the second assay from BD Diagnostics capable of detecting newly emerging MRSA strains with the novel mecC gene. Launched last year, the BD MAX StaphSR Assay reports results for both Staphylococus aureus (SA) and methicillin-resistant Staphylococus aureus (MRSA) and was the first commercially available assay in the U.S. to detect mecC strains of MRSA. Both assays use eXTended Detection Technology to identify a broad range of SA strains including mecA and mecC dropout mutants and new strains of MRSA that may not be detected by other assays.
Molecular assays for MRSA are used in active surveillance programs to identify colonized patients rapidly. Active surveillance is a proven strategy to reduce transmission in healthcare settings and helps prevent infection in vulnerable patients. Inaccurate detection may contribute to uncontrolled transmission of MRSA and inappropriate use of healthcare resources. According to company representatives, with many commercial assays, SA strains carrying SCCmec where the mecA gene is absent (commonly called “dropout mutants”) may be incorrectly classified as MRSA. These false positive results can lead to unnecessary and expensive isolation and treatment of patients. MRSA strains with the newly emerging mecC gene account for nearly 3% of all new MRSA cases in some communities but cannot be detected by all assays. These false negative results can lead to uncontrolled transmission of undetected strains of MRSA. Learn more about the BD MAX MRSA XT assay.