BD Diagnostics, a segment of BD (Becton, Dickinson and Company) designed the BD GeneOhm StaphSR assay, which can identify two deadly healthcare-associated infections (HAIs) - Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA).
S. aureus was identified as a cause of wound infections in the 1880s and was mostly fatal before the discovery of penicillin in the 1940s. However, high levels of resistance were present within two decades. Since methicillin was developed cases of MRSA have increased from being relatively rare in the 1960s and 1079s to being more and more widespread by the 1990s.
This new rapid PCR test could not only save millions in terms of healthcare costs, it should allow physicians to control an outbreak of MRSA by breaking the chain of transmission.
It works by using real-time polymerase chain reaction (PCR) for the amplification of MRSA DNA, detecting the amplicon linking the staphylococcal cassette chromosome mec (SCCmec) carrying methicillin-resistance (mecA) with a sequence unique to S. aureus found in the orfX gene. Unlike most PCR tests, it does not require dedicated equipment and space and can be performed without a dedicated clean area.
"This allows for more appropriate isolation procedures and agent-specific antimicrobial therapy, resulting in reduced patient morbidity and mortality as well as an overall reduction in healthcare costs," said Dr Thomas Davis, Director of Clinical Microbiology, Wishard Memorial Hospital, US.
The assay works directly with blood cultures and requires less technologist time than traditional microbiology assays, which can take two days to get results.
BD has also submitted subsequent nasal swab and wound applications to the FDA. The firm is also developing tests for the detection of two other organisms that cause severe HAIs. These tests will identify the vanA and vanB genes associated with vancomycin-resistant enterococci and the toxin gene associated with Clostridium difficile.
Treat MRSA patients at home
Back in the UK, the National Concern for Healthcare Infections (NCHI), along with seven experts, have produced a report that says the National Health Service (NHS) could save millions of pounds if more MRSA patients were treated at home, instead of at hospital.
The 'MRSA: Separating Fact from Fiction' report states that: "In many cases, if appropriate treatment was available and the patient has no other medical reason for staying in hospital, it is possible for MRSA infection to be treated outside hospital. This can have a number of benefits for the patient and may make the chances of reinfection with MRSA less."
