FDA clears MRSA detection test

The US Food and Drug Administration (FDA) has given clearance to a new product, which simplifies the process, offers improved specificity and decreases the time to result in the identification of methicillin-resistant Staphyloccus aureus (MRSA) identification.

The news is encouraging as one of the reasons MRSA has become so prolific is the inability to detect the bacterium within the crucial time period. Current processes are time-consuming and labour-intensive.

Beckton, Dickinson and Company's (BD), BBL CHROMagar MRSA product allows for the direct detection and identification of most MRSA within 24 hours. The cost benefits associated with reducing nosocomial infections can be significant.

The product utilises a new chromogenic technology, which permits the detection of MRSA using chromogenic substrates and a cephalosporin. MRSA strains will grow in the presence of antibiotics and produce mauve-colored colonies resulting from hydrolysis of the chromogenic substrates.

In clinical evaluations, BBL CHROMagar MRSA displayed 8 per cent greater recovery of MRSA than traditional screening algorithm and has the capability to identify MRSA earlier than most traditional algorithms. BBL CHROMagar MRSA allows for the direct detection and identification of most MRSA within 24 hours, or at 48 hours with a confirmatory test.

"MRSA colonisation is a risk factor for MRSA transmission to other patients. Rapid identification of MRSA will reduce the risk of infection in colonised patients. Clinicians can reduce patient-to- patient transmission by isolating those who are MRSA-colonised," said Dr Bill Jarvis of Emory University School of Medicine.

"The multiple benefits of this rapid identification method will improve patient treatment, reduce the risk of transmission in healthcare settings, and reduce the burden of MRSA in hospitals."

BD's product follows a number of companies, which have produced kits designed to detect the 'superbug' quicker and more effectively. US company, Hardy Diagnostics' MRSA Latex Test for PBP2 claims to detect methicillin resistant S. aureus and methicillin resistant coagulase-negative staphylococci in only 15 minutes.

Canadian lab product distributors, Somagen Diagnostics also have a diagnostic test cleared by the FDA and by Health Canada for the direct detection of nasal colonization by methicillin resistant Staphylococcus aureus (MRSA). Based on the real-time PCR technology, IDI-MRSA test results are available in about one hour after the collection of a nasal swab. By detecting a single genetic sequence specific of MRSA, the IDI-MRSA assay provides a full response in a single step.

The prevalence of nosocomial infections caused by MRSA has been increasing for several years in many countries around the world. The US Centres for Disease Control and Prevention estimates that between 60,000 and 80,000 Americans die each year from nosocomial infections and the cause in the majority of cases is S. aureus.

Reports from the UK National Audit Office state that at any one time, 9 per cent of NHS hospital patients are suffering from an infection such as MRSA, acquired whilst in surgery or as an inpatient on the hospital wards. These 'nosocomial' infections affect 100,000 people annually, costing the National Health Service £1 billion (€1.5bn), and causing up to 5,000 deaths.