This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sakoulas, G.
Right arrow Articles by Qian, Q.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sakoulas, G.
Right arrow Articles by Qian, Q.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, November 2001, p. 3946-3951, Vol. 39, No. 11
0095-1137/01/$04.00+0   DOI: 10.1128/JCM.39.11.3946-3951.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Methicillin-Resistant Staphylococcus aureus: Comparison of Susceptibility Testing Methods and Analysis of mecA-Positive Susceptible Strains

George Sakoulas,1,* Howard S. Gold,1 Lata Venkataraman,2 Paola C. DeGirolami,2 George M. Eliopoulos,1 and Qinfang Qian2

Division of Infectious Diseases, Department of Medicine,1 and Division of Laboratory and Transfusion Medicine, Department of Pathology,2 Beth Israel Deaconess Medical Center, Boston, Massachusetts

Received 24 May 2001/Returned for modification 20 July 2001/Accepted 14 August 2001

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for an increasing number of serious nosocomial and community-acquired infections. Phenotypic heterogeneous drug resistance (heteroresistance) to antistaphylococcal beta-lactams affects the results of susceptibility testing. The present study compared the MRSA-Screen latex agglutination test (Denka Seiken Co., Ltd., Tokyo, Japan) for detection of PBP 2a with agar dilution, the VITEK-1 and VITEK-2 systems (bioMérieux, St. Louis, Mo.), and the oxacillin agar screen test for detection of MRSA, with PCR for the mecA gene used as the "gold standard" assay. Analysis of 107 methicillin-susceptible S. aureus (MSSA) isolates and 203 MRSA isolates revealed that the MRSA-Screen latex agglutination test is superior to any single phenotype-based susceptibility testing method, with a sensitivity of 100% and a specificity of 99.1%. Only one isolate that lacked mecA was weakly positive by the MRSA-Screen latex agglutination test. This isolate was phenotypically susceptible to oxacillin and did not contain the mecA gene by Southern blot hybridization. The oxacillin agar screen test, the VITEK-1 system, the VITEK-2 system, and agar dilution showed sensitivities of 99.0, 99.0, 99.5, and 99%, respectively, and specificities of 98.1, 100, 97.2, and 100%, respectively. The differences in sensitivity or specificity were not statistically significant. Oxacillin bactericidal assays showed that mecA- and PBP 2a-positive S. aureus isolates that are susceptible to antistaphylococcal beta-lactams by conventional methods are functionally resistant to oxacillin. We conclude that the accuracy of the MRSA-Screen latex agglutination method for detection of PBP 2a approaches the accuracy of PCR and is more accurate than any susceptibility testing method used alone for the detection of MRSA.

* Corresponding author. Mailing address: Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Kennedy Building, 6th Floor, 330 Brookline Ave., Boston, MA 02215. Phone: (617) 632-0760. Fax: (617) 632-0766. E-mail: gsakoula{at}caregroup.harvard.edu.

Journal of Clinical Microbiology, November 2001, p. 3946-3951, Vol. 39, No. 11
0095-1137/01/$04.00+0   DOI: 10.1128/JCM.39.11.3946-3951.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Junkins, A. D., Lockhart, S. R., Heilmann, K. P., Dohrn, C. L., Von Stein, D. L., Winokur, P. L., Doern, G. V., Richter, S. S. (2009). BD Phoenix and Vitek 2 Detection of mecA-Mediated Resistance in Staphylococcus aureus with Cefoxitin. J. Clin. Microbiol. 47: 2879-2882 [Abstract] [Full Text]  
  • Kaase, M., Baars, B., Friedrich, S., Szabados, F., Gatermann, S. G. (2009). Performance of MicroScan WalkAway and Vitek 2 for Detection of Oxacillin Resistance in a Set of Methicillin-Resistant Staphylococcus aureus Isolates with Diverse Genetic Backgrounds. J. Clin. Microbiol. 47: 2623-2625 [Abstract] [Full Text]  
  • Ikonomidis, A., Michail, G., Vasdeki, A., Labrou, M., Karavasilis, V., Stathopoulos, C., Maniatis, A. N., Pournaras, S. (2008). In Vitro and In Vivo Evaluations of Oxacillin Efficiency against mecA-Positive Oxacillin-Susceptible Staphylococcus aureus. Antimicrob. Agents Chemother. 52: 3905-3908 [Abstract] [Full Text]  
  • Jain, A., Agarwal, A., Verma, R. K. (2008). Cefoxitin disc diffusion test for detection of meticillin-resistant staphylococci. J Med Microbiol 57: 957-961 [Abstract] [Full Text]  
  • Pape, J., Wadlin, J., Nachamkin, I. (2006). Use of BBL CHROMagar MRSA Medium for Identification of Methicillin-Resistant Staphylococcus aureus Directly from Blood Cultures.. J. Clin. Microbiol. 44: 2575-2576 [Abstract] [Full Text]  
  • Brown, D. F. J., Edwards, D. I., Hawkey, P. M., Morrison, D., Ridgway, G. L., Towner, K. J., Wren, M. W. D., on behalf of the Joint Working Party of the Britis, (2005). Guidelines for the laboratory diagnosis and susceptibility testing of methicillin-resistant Staphylococcus aureus (MRSA). J Antimicrob Chemother 56: 1000-1018 [Abstract] [Full Text]  
  • Miller, M. B., Meyer, H., Rogers, E., Gilligan, P. H. (2005). Comparison of Conventional Susceptibility Testing, Penicillin-Binding Protein 2a Latex Agglutination Testing, and mecA Real-Time PCR for Detection of Oxacillin Resistance in Staphylococcus aureus and Coagulase-Negative Staphylococcus. J. Clin. Microbiol. 43: 3450-3452 [Abstract] [Full Text]  
  • Fernandes, C. J., Fernandes, L. A., Collignon, P., on behalf of the Australian Group on Antimicrobial, (2005). Cefoxitin resistance as a surrogate marker for the detection of methicillin-resistant Staphylococcus aureus. J Antimicrob Chemother 55: 506-510 [Abstract] [Full Text]  
  • Chapin, K. C., Musgnug, M. C. (2004). Evaluation of Penicillin Binding Protein 2a Latex Agglutination Assay for Identification of Methicillin-Resistant Staphylococcus aureus Directly from Blood Cultures. J. Clin. Microbiol. 42: 1283-1284 [Abstract] [Full Text]  
  • Fahr, A.-M., Eigner, U., Armbrust, M., Caganic, A., Dettori, G., Chezzi, C., Bertoncini, L., Benecchi, M., Menozzi, M. G. (2003). Two-Center Collaborative Evaluation of the Performance of the BD Phoenix Automated Microbiology System for Identification and Antimicrobial Susceptibility Testing of Enterococcus spp. and Staphylococcus spp.. J. Clin. Microbiol. 41: 1135-1142 [Abstract] [Full Text]  
  • Horstkotte, M. A., Knobloch, J. K.-M., Rohde, H., Dobinsky, S., Mack, D. (2002). Rapid Detection of Methicillin Resistance in Coagulase-Negative Staphylococci with the VITEK 2 System. J. Clin. Microbiol. 40: 3291-3295 [Abstract] [Full Text]  
  • Sakoulas, G., Eliopoulos, G. M., Moellering, R. C. Jr., Wennersten, C., Venkataraman, L., Novick, R. P., Gold, H. S. (2002). Accessory Gene Regulator (agr) Locus in Geographically Diverse Staphylococcus aureus Isolates with Reduced Susceptibility to Vancomycin. Antimicrob. Agents Chemother. 46: 1492-1502 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»