GENEOHM

BD GeneOhm™ Line of Products

BD GeneOhm™ MRSA ACP Assay

The BD GeneOhm™ MRSA ACP Assay is a qualitative in vitro diagnostic test for the direct detection of methicillin-resistant Staphylococcus aureus (MRSA) DNA from nasal swabs in patients at risk for nasal colonization. The BD GeneOhm MRSA ACP assay builds upon an already proven assay, the BD GeneOhm MRSA assay, by incorporating achromopeptidase (ACP) lysis, which results in fewer assay steps and less hands-on time. The simplified workflow allows for easier, more efficient laboratory detection of MRSA within 2 hours. Compared to culture methods requiring two to five days, this rapid turn-around time can be used to enhance any infection control program.

Identifying the Situation

Rates of S. aureus infection have increased during the past two decades in North America and many European countries. Bacteremia due to S. aureus has been reported to be associated with higher mortality rates (15%-60%).¹ Resistance to methicillin among S. aureus isolates is also a growing problem: up to 60% of nosocomial infections in patients in the intensive care unit (ICU) are due to methicillin-resistant S. aureus.² In fact, MRSA has been identified by the Society for Healthcare and Epidemiology of America (SHEA) as one of the two “most out of control” antimicrobial-resistant pathogens in U.S. hospitals (VRE is the other).³ A 2004 study of a surgical ICU that implemented an active surveillance and contact precautions program found that the use of these methods decreased transmission of MRSA from 5% to 0.9%.⁴

Government and professional organizations are increasingly recommending more proactive procedures to identify, prevent, and control multi-drug resistant organisms (MDROs) such as MRSA.

CDC guidelines from 2002 recommend:⁵

Proper use of antimicrobials – know when to say “no” to vanco (vancomycin)
Preventing transmission – identify and isolate the pathogen
Diagnosing and treating effectively – target the pathogen

SHEA 2003 guidelines go further by recommending:³

Persistent barrier and contact precautions for patients known or suspected to be colonized or infected
Proper hand hygiene for health-care workers
More importantly: active surveillance cultures to identify and control the reservoir of carriers

Prevention and Control of MRSA: The BD GeneOhm™ MRSA Assay

"...even if transmissionto as few as six new patients, none of whom developed infection, was prevented, admission screening would have been cost effective (6)." Extensive studies have demonstrated the advantages of a stringent infection control program including decreased hospital-acquired MRSA infections, length of stay, number of isolated patients, and significant savings from the decreased use of antibiotics.^1,3 The availability of a definitive test result for MRSA within two hours of receiving the specimen enables decisions and actions one to three days earlier than standard culture-based methods.

The BD GeneOhm™ MRSA Assay detects a unique molecular sequence which confers a double specificity: half of this sequence comes from the S. aureus chromosome; the second half is within the genetic element carrying methicillin resistance, the SCCmec cassette.

The speed and flexibility of the BD GeneOhm MRSA ACP Assay provides a powerful new identification tool, which can help reduce the risk of further transmission and infection, helping to reduce healthcare costs.

Results available in less than 2 hours, directly from a specimen
No culture step required
Complete system: reagents, software and instrument

Health Economics

"The use of the real-time PCR assay has decreased lengths of stay for patients discharged to long-term care by almost 2 days, saving the hospital in this study an estimated $205,000 annually (9)." Remarkable annual cost savings have been demonstrated in hospitals implementing active MRSA surveillance programs. With surveillance, hospitals were able to better identify and control the reservoir of MRSA which resulted in significantly reduced rates of infection.

Jernigan et. al. assessed the cost and benefit at a university hospital where active surveillance cultures were performed for high-risk patients.⁷ The study estimated that an active surveillance culture program could save between $20,062 and $462,067 annually while preventing 8 to 41 MRSA infections.³ In another study, Chaix et. al. concluded that targeted screening (identification) and isolation (prevention) are the most cost-effective strategies over a range of MRSA carriage rates on admission, efficacy of the control program and infection rates following transmission.⁸

By offering the capability of delivering definitive MRSA results in less than two hours, the BD GeneOhm™ MRSA Assay from BD has the potential to dramatically improve the cost-effectiveness of an infection control program.

Let us show you how the BD GeneOhm™ MRSA Assay can benefit your facility.

References

1. Cosgrove, SE et al., Comparison of mortality associated with methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteremia: a meta-analysis. Clin Infect Dis. 2003 Jan 1;36(1):53-9.

2. National Nosocomial Infections Surveillance System (NNISS).

3. Muto, CA et al., SHEA Guideline for Preventing Nosocomial Transmission of Multidrug-Resistant Strains of Staphylococcus aureus and Enterococcus. ICHE 2003;24 (5):362-386.

4. Boyce, J.M., Harill N.L., Kohan C., Dumigan D.G., Ligi, C.E. Do infection control measures work for methicillin-resistant Staphylococcus aureus? Infect. Control Hosp. Epidemiol. 2004;25:395-401.

5. Center for Disease Control and Prevention (CDC) website: www.cdc.gov

6. Garner, JS et al., Guideline for isolation precautions in hospitals. The Hospital Infection Control Practices Advisory Committee. ICHE 1996;17 (1):53-80.

7. Jernigan et al., Effectiveness of contact isolation during a hospital outbreak of methicillin-resistant Staphylococcus aureus. Am J Epidemiol. 1996 Mar 1;143(5):496-504. Erratum in: Am J Epidemiol 1996 May 15;143(10):1079.

8. Chaix, C., et al. Control of endemic methicillin-resistant Staphylococcus aureus: a cost-benefit analysis in an intensive care unit. Jama 1999;282(18):1745-51.

9. Diekema, D. J., Dodgson, K. J., Sigurdardottir, B., Pfaller, M. A. Rapid Detection of Antimicrobial-Resistant Organism Carriage: an Unmet Clinical Need. J. Clin. Microbiol. 2004;42 (7): 2879-2883.