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Risk of MRSA Infection in Patients with Intermittent versus Persistent MRSA Nares Colonization

Published online by Cambridge University Press:  20 August 2015

Daniel I. Vigil*
Affiliation:
University of Colorado, Preventive Medicine Residency, Aurora, Colorado
Wesley D. Harden
Affiliation:
University of Colorado, Preventive Medicine Residency, Aurora, Colorado
Anne E. Hines
Affiliation:
Veterans Health Administration Eastern Colorado Healthcare System, Infectious Disease, Denver, Colorado
Patrick W. Hosokawa
Affiliation:
University of Colorado, Adult and Child Center for Outcomes Research and Delivery Science, Aurora, Colorado
William G. Henderson
Affiliation:
University of Colorado, Adult and Child Center for Outcomes Research and Delivery Science, Aurora, Colorado
Mary T. Bessesen
Affiliation:
Veterans Health Administration Eastern Colorado Healthcare System, Infectious Disease, Denver, Colorado University of Colorado Department of Medicine, Division of Infectious Diseases, Aurora, Colorado
*
Address correspondence to Daniel Vigil, MD, University of Colorado Preventive Medicine Residency, 13001 E. 17th Place, Campus Box B119, Aurora, CO 80045 (Daniel.Vigil@ucdenver.edu).

Abstract

OBJECTIVE

To determine the relative risk of invasive methicillin-resistant Staphylococcus aureus (MRSA) infection among non-colonized (NC) patients, intermittently colonized (IC) patients, and persistently colonized (PC) patients.

DESIGN

Observational cohort study of patient data collected longitudinally over a 41-month period.

SETTING

Department of Veterans Affairs Eastern Colorado Healthcare System, a tertiary care medical center.

PATIENTS

Any patient who received ≥5 MRSA nasal swab tests between February 20, 2010, and July 26, 2013. In total, 3,872 patients met these criteria, 0 were excluded, 95% were male, 71% were white, and the mean age was 62.9 years on the date of study entry.

METHODS

Patients were divided into cohorts based on MRSA colonization status. Physicians reviewed medical records to identify invasive infection and were blinded to colonization status. Cox and Kaplan-Meier analyses were used to assess the relationship between colonization status and invasive infection.

RESULTS

In total, 102 patients developed invasive MRSA infections, 16.3% of these were PC patients, 11.2% of these were IC patients, and 0.5% of these were NC patients. PC patients were at higher risk of invasive infection than NC patients (hazard ratio [HR] 36.8; 95% CI, 18.4–73.6; P<.001). IC patients were also at higher risk than NC patients (HR, 22.8; 95% CI, 13.3–39.3; P<.001). The difference in risk between PC and IC patients was not statistically significant (HR, 1.61; 95% CI, 0.94–2.78, P=.084). Alternate analysis methods confirmed these results.

CONCLUSIONS

The risk of invasive MRSA infection is much higher among PC and IC patients, supporting routine clinical testing for colonization. However, this risk is similar among PC and IC patients, suggesting that distinguishing between the 2 colonization states may not be clinically important.

Infect. Control Hosp. Epidemiol. 2015;36(11):1292–1297

Type
Original Articles
Copyright
© 2015 by The Society for Healthcare Epidemiology of America. All rights reserved 

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Footnotes

PREVIOUS PRESENTATION The results of this study were displayed in a poster presentation at IDWeek 2014, October 8–12, Philadelphia, Pennsylvania.

References

REFERENCES

1. von Eiff, C, Becker, K, Machka, K, Stammer, H, Peters, G. Nasal carriage as a source of Staphylococcus aureus bacteremia. N Engl J Med 2001;344:1116.CrossRefGoogle ScholarPubMed
2. Kuehnert, MJ, Kruszon-Moran, D, Hill, HA, et al. Prevalence of Staphylococcus aureus nasal colonization in the United States, 2001–2002. J Infect Dis 2006;193:172179.CrossRefGoogle ScholarPubMed
3. Calfee, DP, Salgado, CD, Milstone, AM, et al. Strategies to prevent methicillin-resistant Staphylococcus aureus transmission and infection in acute care hospitals: 2014 update. Infect Control Hosp Epidemiol 2014;35:S108S132.CrossRefGoogle ScholarPubMed
4. Nouwen, JL, Fieren, MW, Snijders, S, Verbrugh, HA, van Belkum, A. Persistent (not intermittent) nasal carriage of Staphylococcus aureus is the determinant of CPD-related infections. Kidney Int 2005;67:10841092.Google Scholar
5. Nouwen, J, Schouten, J, Schneebergen, P, et al. Staphylococcus aureus carriage patterns and the risk of infections associated with continuous peritoneal dialysis. J Clin Micro 2006;44:22332236.CrossRefGoogle ScholarPubMed
6. Sewell, CM, Clarridge, J, Lacke, C, Weinman, EJ, Young, EJ. Staphylococcal nasal carriage and subsequent infection in peritoneal dialysis patients. JAMA 1982;248:14931495.CrossRefGoogle ScholarPubMed
7. Gupta, K, Martinello, RA, Young, M, Strymish, J, Cho, K, Lawler, E. MRSA nasal carriage patterns and the subsequent risk of conversion between patterns, infection, and death. PLoS One 2013;8:e53674.Google Scholar
8. Huang, SS, Platt, R. Risk of methicillin-resistant Staphylococcus aureus infection after previous infection or colonization. Clin Infect Dis 2003;36:281285.CrossRefGoogle ScholarPubMed
9. Wertheim, HF, Melles, DC, Vos, MC, et al. The role of nasal carriage in Staphylococcus aureus infections. Lancet Infect Dis 2005;5:751762.Google Scholar
10. Gupta, K, Strymish, J, Abi-Haidar, Y, Williams, SA, Itani, KM. Preoperative nasal methicillin-resistant Staphylococcus aureus status, surgical prophylaxis, and risk-adjusted postoperative outcomes in veterans. Infect Control Hosp Epidemiol 2011;32:791796.Google Scholar
11. Kalra, L, Camacho, F, Whitener, CJ, et al. Risk of methicillin-resistant Staphylococcus aureus surgical site infection in patients with nasal MRSA colonization. Am J Infect Control 2013;41:12531257.Google Scholar
12. Datta, R, Shah, A, Huang, SS, et al. High nasal burden of methicillin-resistant Staphylococcus aureus increases risk of invasive disease. J Clin Micro 2014;52:312314.CrossRefGoogle ScholarPubMed
13. Engemann, JJ, Carmeli, Y, Cosgrove, SE, et al. Adverse clinical and economic outcomes attributable to methicillin resistance among patients with Staphylococcus aureus surgical site infection. Clin Infect Dis 2003;36:592598.CrossRefGoogle ScholarPubMed
14. Cosgrove, SE, Sakoulas, G, Perencevich, EN, Schwaber, MJ, Karchmer, AW, Carmeli, Y. Comparison of mortality associated with methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteremia: a meta-analysis. Clin Infect Dis 2003;36:5359.Google Scholar
15. Honda, H, Krauss, MJ, Coopersmith, CM, et al. Staphylococcus aureus nasal colonization and subsequent infection in intensive care unit patients: does methicillin resistance matter? Infect Control Hosp Epidemiol 2010;31:584591.Google Scholar
16. Pujol, M, Pena, C, Pallares, R, et al. Nosocomial Staphylococcus aureus bacteremia among nasal carriers of methicillin-resistant and methicillin-susceptible strains. Am J Med 1996;100:509516.Google Scholar
17. Safdar, N, Bradley, EA. The risk of infection after nasal colonization with Staphylococcus aureus . Am J Med 2008;121:310315.CrossRefGoogle ScholarPubMed
18. Nouwen, JL, Ott, A, Kluytmans-Vandenbergh, MF, et al. Predicting the Staphylococcus aureus nasal carrier state: derivation and validation of a “culture rule”. Clin Infect Dis 2004;39:806811.CrossRefGoogle ScholarPubMed
19. VandenBergh, MF, Yzerman, EP, van Belkum, A, Boelens, HA, Sijmons, M, Verbrugh, HA. Follow-up of Staphylococcus aureus nasal carriage after 8 years: redefining the persistent carrier state. J Clin Micro 1999;37:31333140.CrossRefGoogle ScholarPubMed
20. van Belkum, A, Verkaik, NJ, de Vogel, CP, et al. Reclassification of Staphylococcus aureus nasal carriage types. J Infect Dis 2009;199:18201826.Google Scholar
21. Horan, TC, Andrus, M, Dudeck, MA. CDC/NHSN surveillance definition of health care-associated infection and criteria for specific types of infections in the acute care setting. Am J Infect Control 2008;36:309332.Google Scholar
22. Feil, EJ, Cooper, JE, Grundmann, H, et al. How clonal is Staphylococcus aureus? J Bacteriol 2003;185:33073316.Google Scholar
23. Melles, DC, Gorkink, RF, Boelens, HA, et al. Natural population dynamics and expansion of pathogenic clones of Staphylococcus aureus . J Clin Invest 2004;114:17321740.CrossRefGoogle ScholarPubMed