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Impact of an Assay That Enables Rapid Determination of Staphylococcus Species and Their Drug Susceptibility on the Treatment of Patients with Positive Blood Culture Results

Published online by Cambridge University Press:  02 January 2015

Mark Parta ,
Melanie Goebel ,
Jimmy Thomas ,
Mahsa Matloobi ,
Charles Stager  and
Daniel M. Musher
Mark Parta*
Affiliation:
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas Baylor College of Medicine, Houston, Texas
Melanie Goebel
Affiliation:
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas
Jimmy Thomas
Affiliation:
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas
Mahsa Matloobi
Affiliation:
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas
Charles Stager
Affiliation:
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas Baylor College of Medicine, Houston, Texas
Daniel M. Musher
Affiliation:
Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas Baylor College of Medicine, Houston, Texas
*
Baylor College of Medicine, 1709 Dryden Road, Suite 6.12, MS: BCM 620.625, Houston, TX 77030, (parta@bcm.edu)
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Extract

Objective.

To determine whether an earlier determination of staphylococcal species and their antibiotic susceptibility decreases unnecessary antistaphylococcal treatment and/or facilitates earlier appropriate treatment.

Methods.

We used the Xpert MRSA/SA BC system (Cepheid) for immediate determination of species and their drug susceptibility in patients whose blood cultures revealed gram-positive cocci in clusters. We compared the treatment of patients whose physicians received early notification of these results (group 1) with the treatment of patients in a historical cohort with delayed reporting after traditional microbiological studies (group 2). Outcomes were analyzed according to whether blood culture was positive for Staphylococcus species other than S. aureus, methicillin-susceptible S. aureus (MSSA), or methicillin-resistant S. aureus (MRSA) and whether the drugs used were appropriate for methicillin-susceptible or methicillin-resistant staphylococci (hereafter referred to as “MSS drug” or “MRS drug” therapy, respectively).

Results.

There were 44 (76%) of 58 patients with bacteremia due to Staphylococcus species other than S. aureus in group 1 and 58 (55%) of 106 patients with bacteremia due to Staphylococcus species other than S. aureus in group 2 who received no antistaphylococcal antibiotics (P <.01). Five (6%) of 89 patients in group 1 and 31 (25%) of 123 patients in group 2 received 0-168 hours (0-7 days) of MRS drug therapy (P < .01). Among patients with MSSA bacteremia, the mean time to initiation of appropriate therapy was 5.2 hours in group 1 and 49.8 hours in group 2 (P < = .007). Excluding patients who received MRS drug therapy for unrelated conditions, the mean duration of treatment was 19.7 hours in group 1 and 80.7 hours in group 2 (P = .003). Six (50%) of the 12 patients in group 1 and 39 (81%) of the 48 patients in group 2 received MRS drug therapy for MSSA bacteremia (P = .025). Time to initiation of therapy for MRSA bacteremia did not differ between groups.

Conclusions.

The use of an assay with rapid results reduced the use of antistaphylococcal therapy among patients who did not have S. aureus bacteremia; it also decreased the use of MRS drug therapy and led to earlier appropriate therapy among patients with MSSA bacteremia.

Type
Original Articles
Information
Infection Control & Hospital Epidemiology , Volume 31 , Issue 10 , October 2010 , pp. 1043 - 1048
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2010

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References

1.Awad, SS, Palacio, CH, Subramanian, A, et al.Implementation of a methicillin-resistant Staphylococcus aureus (MRSA) prevention bundle results in decreased MRSA surgical site infections. Am J Surg 2009;198(5):607–610.Google Scholar
2.Parta, M, Goebel, M, Matloobi, M, Stager, C, Musher, DM. Identification of methicillin-resistant or methicillin-susceptible Staphylococcus aureus in blood cultures and wound swabs by GeneXpert. J Clin Microbiol 2009;47(5):1609–1610.CrossRefGoogle ScholarPubMed
3.Xpert MRSA/SA BC. Instruction manual. Sunnyvale, CA: Cepheid; 2008.Google Scholar
4.Chang, FY, Peacock, JE Jr, Musher, DM, et al.Staphylococcus aureus bacteremia: recurrence and the impact of antibiotic treatment in a prospective multicenter study. Medicine (Baltimore) 2003;82(5):333–339.Google Scholar
5.Kim, SH, Kim, KH, Kim, HB, et al.Outcome of vancomycin treatment in patients with methicillin-susceptible Staphylococcus aureus bacteremia. Antimicrob Agents Chemother 2008;52(1):192–197.CrossRefGoogle ScholarPubMed
6.Fang, CT, Shau, WY, Hsueh, PR, et al.Early empirical glycopeptide therapy for patients with methicillin-resistant Staphylococcus aureus bacteraemia: impact on the outcome. J Antimicrob Chemother 2006;57(3):511–519.CrossRefGoogle ScholarPubMed
7.Gomez, J, Garcia-Vazquez, E, Banos, R, et al.Predictors of mortality in patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia: the role of empiric antibiotic therapy. Eur J Clin Microbiol Infect Dis 2007;26(4):239–245.Google Scholar
8.Kim, SH, Park, WB, Lee, KD, et al.Outcome of inappropriate initial antimicrobial treatment in patients with methicillin-resistant Staphylococcus aureus bacteraemia. J Antimicrob Chemother 2004;54(2):489–497.Google Scholar
9.Schramm, GE, Johnson, JA, Doherty, JA, Micek, ST, Kollef, MH. Methicillin-resistant Staphylococcus aureus sterile-site infection: the importance of appropriate initial antimicrobial treatment. Crit Care Med 2006;34(8):2069–2074.Google Scholar
10.Kim, SH, Park, WB, Lee, CS, et al.Outcome of inappropriate empirical antibiotic therapy in patients with Staphylococcus aureus bacteraemia: analytical strategy using propensity scores. Clin Microbiol Infect 2006;12(1):13–21.Google Scholar
11.Mason, EO, Lamberth, LB, Hammerman, WA, Hulten, KG, Versalovic, J, Kaplan, SL. Vancomycin MICs for Staphylococcus aureus varyby detection method and have subtly increased in a pediatric population since 2005. J Clin Microbiol 2009;47(6):1628–1630.CrossRefGoogle Scholar
12.Tenover, FC, Moellering, RC Jr. The rationale for revising the Clinical and Laboratory Standards Institute vancomycin minimal inhibitory concentration interpretive criteria for Staphylococcus aureus. Clin Infect Dis 2007;44(9):1208–1215.Google Scholar
13.Alos, JI, Garcia-Canas, A, Garcia-Hierro, P, Rodriguez-Salvanes, F. Vancomycin MICs did not creep in Staphylococcus aureus isolates from 2002 to 2006 in a setting with low vancomycin usage. J Antimicrob Chemother 2008;62(4):773–775.Google Scholar