1887

Abstract

Earlier targeted therapy for bacteraemia optimizes patient outcomes and reduces broad spectrum antibiotic use. Standardized susceptibility testing results are available at 36–48 h. Direct disc susceptibility testing from blood culture broth reduces time to results but the inoculum is not standardized. No studies have looked at the clinical utility of direct susceptibility results. This retrospective cohort study aimed to assess the correlation between direct and formal testing methods as well as the clinical utility of direct susceptibility results. 160 episodes of bacteraemia with paired direct and formal susceptibility testing were studied. Direct disc testing was performed on blood culture broth. Formal testing was performed on isolates, using automated broth microdilution or Etests. The rate of error was 9.0 % (95 % CI 7.0–11.6 %). In 10 cases (6.3 %, 95 % CI 3.0–11.2 %), inappropriate antibiotics were used due to direct susceptibility results, including two cases with ineffective (as opposed to too broad) antibiotics being used. Antibiotics were changed in 28.1 % of cases once direct susceptibility data was available. There was a decreased time to effective antibiotics in 9.3 % (95 % CI 5.3–15.0 %), and a decreased time to a targeted antibiotics in 14.3 % (95 % CI 9.3–20.8 %) of cases. Despite the error rate, the advantages of earlier times to effective and targeted antibiotics justifies continuing direct testing in bacteraemia episodes with Gram-negative rods. In the Gram-positive group, given the contamination rate, the availability of adjunctive PCR, and the fact that early identification of the isolate could equally influence antibiotic choices, direct susceptibility testing may no longer be warranted.

Loading

Article metrics loading...

/content/journal/jmm/10.1099/jmm.0.000259
2016-06-01
2024-12-08
Loading full text...

Full text loading...

/deliver/fulltext/jmm/65/6/501.html?itemId=/content/journal/jmm/10.1099/jmm.0.000259&mimeType=html&fmt=ahah

References

  1. Adams D. N. 2005; Shortcut method for extraction of Staphylococcus aureus DNA from blood cultures and conventional cultures for use in real-time PCR assays. J Clin Microbiol 43:2932–2933 [View Article][PubMed]
    [Google Scholar]
  2. Adams D. N. 2006; Shortcut detection of the vanB gene cluster in enterococci by a duplex real-time PCR assay. Pathology 38:349–352 [View Article][PubMed]
    [Google Scholar]
  3. Barenfanger J., Drake C., Kacich G. 1999; Clinical and financial benefits of rapid bacterial identification and antimicrobial susceptibility testing. J Clin Microbiol 37:1415–1418[PubMed]
    [Google Scholar]
  4. Beuving J., Wolffs P. F., Hansen W. L., Stobberingh E. E., Bruggeman C. A., Kessels A., Verbon A. 2015; Impact of same-day antibiotic susceptibility testing on time to appropriate antibiotic treatment of patients with bacteraemia: A randomised controlled trial. Eur J Clin Microbiol Infect Dis 34:831–838 [View Article][PubMed]
    [Google Scholar]
  5. Clinical and Laboratory Standards Institute (CLSI) 2014; M100-S24 Performance Standards for Antimicrobial Susceptibility Testing; Twenty-Fourth Informational Supplement.
  6. De Cueto M., Ceballos E., Martinez-Martinez L., Perea E. J., Pascual A. 2004; Use of positive blood cultures for direct identification and susceptibility testing with the Vitek 2 system. J Clin Microbiol 42:3734–3738 [View Article][PubMed]
    [Google Scholar]
  7. Edelmann A., Pietzcker T., Wellinghausen N. 2007; Comparison of direct disk diffusion and standard microtitre broth dilution susceptibility testing of blood culture isolates. J Med Microbiol 56:202–207 [View Article][PubMed]
    [Google Scholar]
  8. European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2012; Direct antimicrobial susceptibility testing guidelines. http://www.eucast.org/
  9. Fay D., Oldfather J. E. 1979; Standardization of direct susceptibility test for blood cultures. J Clin Microbiol 9:347–350[PubMed]
    [Google Scholar]
  10. Idelevich E. A., Schüle I., Grünastel B., Wüllenweber J., Peters G., Becker K. 2014; Acceleration of antimicrobial susceptibility testing of positive blood cultures by inoculation of Vitek 2 cards with briefly incubated solid medium cultures. J Clin Microbiol 52:4058– 4062 [View Article][PubMed]
    [Google Scholar]
  11. Jo S. J., Park K. G., Han K., Park D. J., Park Y. J. 2016; Direct identification and antimicrobial susceptibility testing of bacteria from positive blood culture bottles by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and the vitek 2 system. Ann Lab Med 36:117–123 [View Article][PubMed]
    [Google Scholar]
  12. Joseph N. M., Bhanupriya B., Shewade D. G., Harish B. N. 2015; Relationship between antimicrobial consumption and the incidence of antimicrobial resistance in Escherichia coli and Klebsiella pneumoniae isolates. J Clin Diagn Res 9:DC08–12 [View Article][PubMed]
    [Google Scholar]
  13. Kumar A., Roberts D., Wood K. E., Light B., Parrillo J. E., Sharma S., Suppes R., Feinstein D., Zanotti S. et al. 2006; Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock. Crit Care Med 34:1589–1596 [View Article][PubMed]
    [Google Scholar]
  14. Leibovici L., Shraga I., Drucker M., Konigsberger H., Samra Z., Pitlik S. D. 1998; The benefit of appropriate empirical antibiotic treatment in patients with bloodstream infection. J Intern Med 244:379–386 [View Article][PubMed]
    [Google Scholar]
  15. Levy M. M., Fink M. P., Marshall J. C., Abraham E., Angus D., Cook D., Cohen J., Opal S. M., Vincent J. L., Ramsay G. 2003; 2001 SCCM/ESICM/ACCP/ATS/SIS international sepsis definitions conference. Intensive Care Med 29:530–538 [View Article][PubMed]
    [Google Scholar]
  16. Mahrer S., Reinbott R., Bell S. 2008; Blood cultures- A retrospective evaluation of direct antibiotic susceptibility testing using positive broth cultures detected by the bact-alert system. Australian Society for Microbiology. Annual Conference Adelaide, Australia
    [Google Scholar]
  17. Nelovkov A., Pirozkova L., Ivanova M., Kolesnikova V. 2012; Direct blood culture antimicrobial susceptibility testing in an East-Tallinn central hospital, Estonia. 22nd European Congress of Clinical Microbiology and Infectious Diseases (ECCMID)
    [Google Scholar]
  18. Paul M., Shani V., Muchtar E., Kariv G., Robenshtok E., Leibovici L. 2010; Systematic review and meta-analysis of the efficacy of appropriate empiric antibiotic therapy for sepsis. Antimicrob Agents Chemother 54:4851–4863 [View Article][PubMed]
    [Google Scholar]
  19. Rogues A. M., Dumartin C., Amadéo B., Venier A. G., Marty N., Parneix P., Gachie J. P. 2007; Relationship between rates of antimicrobial consumption and the incidence of antimicrobial resistance in Staphylococcus aureus and Pseudomonas aeruginosa isolates from 47 French hospitals. Infect Control Hosp Epidemiol 28:1389–1395 [View Article][PubMed]
    [Google Scholar]
  20. Romero-Gómez M. P., Gómez-Gil R., Paño-Pardo J. R., Mingorance J. 2012; Identification and susceptibility testing of microorganism by direct inoculation from positive blood culture bottles by combining MALDI-TOF and Vitek-2 compact is rapid and effective. J Infect 65:513–520 [View Article][PubMed]
    [Google Scholar]
  21. Tan T. Y., Ng L. S., Kwang L. L. 2008; Evaluation of disc susceptibility tests performed directly from positive blood cultures. J Clin Pathol 61:343–346 [View Article][PubMed]
    [Google Scholar]
  22. Yu F., Lin M., Lee J., Lian Y., Lin C., Chen C., Wang G. 2010; Comparison of antimicrobial susceptibility testing of isolates from blood cultures by direct inoculation method and PHOENIX. Journal of Biomed Lab Science 2011 23:23–28
    [Google Scholar]
/content/journal/jmm/10.1099/jmm.0.000259
Loading
/content/journal/jmm/10.1099/jmm.0.000259
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error