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The Effect of Rapid Screening for Methicillin-Resistant Staphylococcus aureus (MRSA) on the Identification and Earlier Isolation of MRSA-Positive Patients

  • Eilish Creamer (a1), Anthony Dolan (a1), Orla Sherlock (a1), Toney Thomas (a2), John Walsh (a2), Joan Moore (a3), Edmond Smyth (a3), Eoghan O'Neill (a1), Anna Shore (a4), Derek Sullivan (a4), Angela S. Rossney (a5), Robert Cunney (a6), David Coleman (a4) and Hilary Humphreys (a1) (a3)...

Abstract

Objectives.

(1) To determine whether rapid screening with polymerase chain reaction (PCR) assays leads to the earlier isolation of patients at risk for methicillin-resistant Staphylococcus aureus (MRSA) colonization, (2) to assess compliance with routine MRSA screening protocols, (3) to confirm the diagnostic accuracy of the Xpert MRSA real-time PCR assay (Cepheid) by comparison with culture, and (4) to compare turnaround times for PCR assay results with those for culture results.

Design.

Before-and-after study conducted in a 700-bed acute tertiary care referral hospital. Study periods were (1) a 5-week period before PCR testing began, (2) a 10-week period when the PCR assay was used, and (3) a 5-week period after PCR testing was discontinued.

Results.

Among 489 at-risk patients, MRSA was isolated from 20 (33%) of 60 patients during period 1, 77 (22%) of 349 patients during period 2, and 18 (23%) of 80 patients during period 3. Twenty-two (27%) of 82 at-risk patients were not screened during period 1, compared with 40 (10%) of 389 at-risk patients not screened during period 2 (P < .001). More MRSA-positive patients were preemptively isolated during periods 1 and 3 compared with period 2 (34 [24%] of 140 vs 28 [8%] of 389; P < .001); however, more MRSA-positive patients were isolated after notification of MRSA-positive results during period 2 (47 [13%] of 349) compared with periods 1 and 3 (2 [1%] of 140; P < .001). The sensitivity, specificity, positive predictive value, and negative predictive value of the PCR assay were 95%, 97%, 82%, and 99%, respectively. The mean turnaround time from receipt of specimens in the laboratory to PCR assay result was 2.6 hours.

Conclusions.

Rapid screening with the Xpert MRSA PCR assay facilitated compliance with screening policies and the earlier isolation of MRSA-positive Patients. Discrepant results confirm that PCR testing should be used as a screening tool rather than as a diagnostic tool.

Copyright

Corresponding author

Department of Clinical Microbiology, RCSI Education and Research Centre, Beaumont Hospital, PO Box 9063, Beaumont Road, Dublin 9, Ireland (eilishcreamer@rcsi.ie)

References

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1. SARI Infection Control Subcommittee. The Control and Prevention of MRSA in Hospital and in the Community. Dublin, Ireland: Health Protection Surveillance Centre, 2005.
2. Muto, CA, Jernigan, JA, Ostrowsky, BE, et al. SHEA guideline for preventing nosocomial transmission of multidrug-resistant strains of Staphylococcus aureus and Enterococcus . Infect Control Hosp Epidemiol 2003;24: 362386.
3. Huang, SS, Rifas-Shiman, SL, Warren, DK, et al. Improving methicillin-resistant Staphylococcus aureus surveillance and reporting in intensive care units. J Infect Dis 2007;195:330338.
4. Mangini, E, Segal-Maurer, S, Burns, J, et al. Impact of contact and droplet precautions on the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus infection. Infect Control Hosp Epidemiol 2007;28: 12611266.
5. Muder, RR, Cunningham, C, McCray, E, et al. Implementation of an industrial systems-engineering approach to reduce the incidence of methicillin-resistant Staphylococcus aureus infection. Infect Control Hosp Epidemiol 2008;29:702708.
6. Robicsek, A, Beaumont, JL, Paule, SM, et al. Universal surveillance for methicillin-resistant Staphylococcus aureus in 3 affiliated hospitals. Ann Intern Med 2008;148:409418.
7. Jeyaratnam, D, Whitty, CJ, Phillips, K, et al. Impact of rapid screening tests on acquisition of meticillin resistant Staphylococcus aureus: cluster randomised crossover trial. BMJ 2008;336:927930.
8. Kluytmans, J. Control of meticillin-resistant Staphylococcus aureus (MRSA) and the value of rapid tests. J Hosp Infect 2007;65(suppl 2):100104.
9. Uçkay, I, Sax, H, Iten, A, et al. Effect of screening for methicillin-resistant Staphylococcus aureus carriage by polymerase chain reaction on the duration of unnecessary preemptive contact isolation. Infect Control Hosp Epidemiol 2008;29:10771079.
10. Aldeyab, MA, Kearney, MP, Hughes, CM, et al. Can the use of a rapid polymerase chain screening method decrease the incidence of nosocomial meticillin-resistant Staphylococcus aureus? J Hosp Infect 2009;71:2228.
11. Harbarth, S, Sax, H, Fankhauser-Rodriguez, C, Schrenzel, J, Agostinho, A, Pittet, D. Evaluating the probability of previously unknown carriage of MRSA at hospital admission. Am J Med 2006;119:275.e15275.e23.
12. Keshtgar, MR, Khalili, A, Coen, PG, et al. Impact of rapid molecular screening for meticillin-resistant Staphylococcus aureus in surgical wards. Br J Surg 2008;95:381386.
13. Gilpin, DF, Tunney, MM, Funston, C, Savage, K, Gardiner, A, Kearney, MP. Rapid detection of MRSA in a routine diagnostic laboratory using a realtime PCR assay. J Hosp Infect 2007;67:9799.
14. Rajan, L, Smyth, E, Humphreys, H. Screening for MRSA in ICU patients: how does PCR compare with culture? J Infect 2007;55:353357.
15. 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;46:32853290.
16. Rossney, AS, Herra, CM, Fitzgibbon, MM, Morgan, PM, Lawrence, MJ, O'Connell, B. Evaluation of the IDI-MRSA assay on the SmartCycler real-time PCR platform for rapid detection of MRSA from screening specimens. Eur J Clin Microbiol Infect Dis 2007;26:459466.
17. Buhlmann, M, Bogli-Stuber, K, Droz, S, Muhlemann, K. Rapid screening for carriage of methicillin-resistant Staphylococcus aureus by PCR and associated costs. J Clin Microbiol 2008;46:21512154.
18. Straelens, MJ, Denis, O. Rapid molecular detection of methicillin-resistant Staphylococcus aureus: a cost-effective tool for infection control in critical care? [commentary]. Crit Care 2006;10:128. http://ccforum.com/content/10/2/128. Accessed April 24, 2009.
19. Francois, P, Bento, M, Renzi, G, Harbarth, S, Pittet, D, Schrenzel, J. Evaluation of three molecular assays for rapid identification of methicillin-resistant Staphylococcus aureus . J Clin Microbiol 2007;45:20112013.
20. van Hal, SJ, Stark, D, Lockwood, B, Marriott, D, Harkness, J. Methicillin-resistant Staphylococcus aureus (MRSA) detection: comparison of two molecular methods (IDI-MRSA PCR assay and GenoType MRSA Direct PCR assay) with three selective MRSA agars (MRSA ID, MRSASelect, and CHROMagar MRSA) for use with infection-control swabs. J Clin Microbiol 2007;45:24862490.
21. Wolk, DM, Picton, E, Johnson, D, et al. Multicenter evaluation of the Cepheid Xpert methicillin-resistant Staphylococcus aureus (MRSA) test as a rapid screening method for detection of MRSA in nares. J Clin Microbiol 2009;47:758764.
22. Cunningham, R, Jenks, P, Northwood, J, Wallis, M, Ferguson, S, Hunt, S. Effect on MRSA transmission of rapid PCR testing of patients admitted to critical care. J Hosp Infect 2007;65:2428.
23. Daly, LE, Bourke, GJ, McGilvray, JW. Interpretation and Uses of Medical Statistics. Oxford, UK: Blackwell Scientific; 1991.
24. Gopal Rao, G, Michalczyk, P, Nayeem, N, Walker, G, Wigmore, L. Prevalence and risk factors for meticillin-resistant Staphylococcus aureus in adult emergency admissions—a case for screening all patients? J Hosp Infect 2007;66: 1521.
25. Dancer, SJ. Considering the introduction of universal MRSA screening. J Hosp Infect 2008;69:315320.
26. Harbarth, S, Fankhauser, C, Schrenzel, J, et al. Universal screening for methicillin-resistant Staphylococcus aureus at hospital admission and nosocomial infection in surgical Patients. JAMA 2008;299:11491157.
27. Shore, AC, Rossney, AS, O'Connell, B, et al. Detection of staphylococcal cassette chromosone mec-associated DNA segments in multiresistant methi-cillin-susceptible Staphylococcus aureus (MSSA) and identification of Staphylococcus epidermidis ccrAB4 in both methicillin-resistant S. aureus and MSSA. Antimicrob Agents Chemother 2008;52:440741419.
28. Carroll, KC. Rapid diagnostics for methicillin-resistant Staphylococcus aureus: current status. Mol Diagn Ther 2008;12:1524.

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