| Current and Future Prospects Cepheid's next generation platform, the Xpert® system, addressed some of the problematic factors by simplifying the workflow and making on-demand testing feasible. The assay targets the SCCmec-orfX junction, and utilizes a self-contained cartridge containing all the reagents necessary for real time PCR. Swabs are placed into an elution fluid and vortexed; an aliquot is dispensed into a reagent cartridge, which is installed on the Xpert platform. Results are available in approximately 75 minutes. Capital investment for equipment and ongoing reagent costs remain a consideration with this system. Another consideration for laboratories is throughput. Although the Xpert® platform offers excellent turnaround time, the largest system has 16 modules. Facilities that need to process very large volumes of specimens will require multiple modules, adding to capital considerations.Large volume platforms that automate sample preparation, extraction, amplification, and detection in a real time format would represent the ideal, walk-away solution for many laboratories, as well as a target for development for manufacturers. | View Page |
| References BD GeneOhm™ MRSA [package insert]. Quebec, Qc, Canada: BD Diagnostics; 2009. Available at: http://www.bd.com/geneohm/english/products/pdfs/mrsa_pkginsert.pdf. Accessed February 22, 2012.Bonetta L. Prime time for real-time PCR. Nature Methods. 2005;2:305-312. Available at: http://www.nature.com/nmeth/journal/v2/n4/full/nmeth0405-305.html. Accessed February 22, 2012.Boughton B. Universal PCR Screening for MRSA May Cut Costs, Reduce Infection. In Medscape Medical News. Available at: http://www.medscape.com/viewarticle/708813. Accessed February 22, 2012.CDC Response: A Year in Review. Centers for Disease Control and Prevention Website. Available at: http://www.cdc.gov/h1n1flu/yearinreview.htm. Accessed February 22, 2012.Centers for Disease Control and Prevention. Evaluation of Rapid Influenza Diagnostic Tests for Detection of Novel Influenza A (H1N1) Virus ---United States, 2009. Morbidity and Mortality Weekly Report. August 7, 2009;58(30):826-829. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5830a2.htm. Accessed February 22, 2012.Department of Biochemistry. University at Buffalo, School of Medicine and Biomedical Sciences Website. Available at: http://www.smbs.buffalo.edu/bch/Labs/SinhaLab/Protocols/RT-PCR.pdf. Accessed February 22, 2012.Desjardins M, Guibord C, Lalonde B, Toye B, Ramotar K. Evaluation of the IDI-MRSA Assay for the Detection of Methicillin-Resistant Staphylococcus aureus from Nasal and Rectal Specimens Pooled in Selective Broth. J Clin Microbiol. 2006 April;44(4):1219-1223. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1448652/. Accessed February 22, 2012.Eastwood K, Else P, Charlett A, Wilcox M. Comparison C. difficile detection methods. J Clin Microbiol. 2009;doi:10.1128/JCM.01082-09. Available at: http://jcm.asm.org/cgi/content/short/JCM.01082-09v1Farley JE, Stamper PD, Ross T, Cai M, Speser S, Carroll KC. Comparison of the BD GeneOhm Methicillin-Resistant Staphylococcu aureus (MRSA) PCR Assay to Culture by Use of BBL CHROMagar MRSA for Detection of MRSA in Nasal Surveillance Cultures from an At-Risk Community Population. J Clin Microbiol. 2008;46(2):743-746. Available at: http://jcm.asm.org/content/46/2/743.full. Accessed February 22, 2012.Forrest GN, Mehta S, Weeks E, Lincalis DP, Johnson JK, Venezia RA. Impact of Rapid In Situ Hybridization Testing on Coagulase Negative Staphylocci Positive Blood Cultures. J Antimicrob Chemother. 2006;58(1):154-158. Available at: http://jac.oxfordjournals.org/content/58/1/154.full. Accessed February 22, 2012.Garcia LS, Isenberg HD, eds-in-chief. Clinical Microbiology Procedures Handbook. 2nd ed. Washington, DC: ASM Press; 2007.Hindiyeh M, Hillyard DR, Carroll KC. Evaluation of the Prodesse Hexaplex Multiplex PCR Assay for Direct Detection of Seven Respiratory Viruses in Clinical Specimens. Am J Clin Pathol. 2001;116:218-224. Available at: http://ajcp.ascpjournals.org/content/116/2/218.full.pdf. Accessed February 22, 2012.Hunt M. Real Time PCR. University of South Carolina School of Medicine Website. Available at: http://pathmicro.med.sc.edu/pcr/realtime-home.htm. Accessed February 22,2012.Interim Guidance for Influenza Surveillance: Prioritizing RT-PCR Testing in Laboratories. Centers for Disease Control and Prevention Website. Available at: http://www.cdc.gov/h1n1flu/screening.htm. Accessed February 22, 2012.Interim Guidance for the Detection of Novel Influenza A Virus Using Rapid Influenza Diagnostic Tests. Centers for Disease Control and Prevention Website. Available at: http://www.cdc.gov/h1n1flu/guidance/rapid_testing.htm. Accessed February 22, 2012.Levenson D. Molecular Testing for Respiratory Viruses. In Clinical Laboratory News. March 2008: Vol 34, No 3. Washington, DC: AACC Press; 2008. Available at: http://www.aacc.org/publications/cln/2008/mar/Pages/cover1_0308.aspx. Accessed February 22, 2012.Morshed MG, Lee MK, Jorgensen D, Issac-Renton JL. Molecular methods used in clinical laboratory: prospects and pitfalls. FEMS Immunol Med Microbiol. 2007;49:184-191. Available at: http://www.canlyme.com/morshed_pcr.pdf. Accessed February 22, 2012.Paillard F, Hill CS. Direct nucleic acid diagnostics tests for bacterial infectiousdiseases: Streptococcal pharyngitis, pulmonary tuberculosis, vaginitis, chlamydial and gonococcal infections. MLO-online. 2004;10-15. Available at: http://www.mlo-online.com/articles/0104/mlo0104coverstory.pdf. Accessed February 22, 2012.PCR: an outstanding method. Roche Website. Available at: http://www.roche.com/pages/facets/pcr_e.pdf. Accessed February 22, 2012.Persing DH, ed-in-chief.Molecular Microbiology, Diagnostic Principles and Practice. 2nd ed. Washington, DC: ASM Press; 2010.Pfaller MA. Molecular Approaches to Diagnosing and Managing Infectious Diseases: Practicality and Costs. Emerg Infect Dis. 2001;eid0702. Available at: http://wwwnc.cdc.gov/eid/article/7/2/70-0312_article.htm. Accessed February 22, 2012.Rossney AS, Herra CM, Brennan GI, Morgan PM, O'Connell B. Evaluation of the Xpert Methicillin-Resistant Staphylococcus aureus (MRSA) Assay Using the GeneXpert Real-Time PCR Platform for Rapid Detection of MRSA From Screening Specimens. J Clin Microbiol. 2008;46(10):3285-3290. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2566096/. Accessed February 22, 2012.The 2009 H1N1 Pandemic: Summary Highlights, April 2009-April 2010. Centers for Disease Control and Prevention Website. Available at: http://www.cdc.gov/h1n1flu/cdcresponse.htm. Accessed February 22, 2012.Timeline of PCR and Roche. Roche Website. Available at: http://molecular.roche.com/About/pcr/Pages/PCRTimeline.aspx. Accessed February 22, 2012. | View Page |
