Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-16T19:37:52.454Z Has data issue: false hasContentIssue false

Compatibility of Pulsed-Field Gel Electrophoresis Findings and Clinical Criteria Commonly Used to Distinguish Between True Coagulase-Negative Staphylococcal Bacteremia and Contamination

Published online by Cambridge University Press:  02 January 2015

Süheyla Serin Senger*
Affiliation:
Department of Infectious Diseases and Clinical Microbiology, Dokuz Eylül University, Izmir, Turkey Department of Infectious Diseases and Clinical Microbiology, Baskent University, Ankara, Turkey
Mine Erdenizmenli Saccozza
Affiliation:
Department of Infectious Diseases and Clinical Microbiology, Dokuz Eylül University, Izmir, Turkey
Ayşe Yüce
Affiliation:
Department of Infectious Diseases and Clinical Microbiology, Dokuz Eylül University, Izmir, Turkey
*
Department of Infectious Diseases and Clinical Microbiology, Baskent University, Ankara, Turkey (suheylDepartment ofDepartment ofas@baskent-ank.edu.tr)

Abstract

Objectives.

To evaluate the specificity and sensitivity of the clinical criteria widely used to differentiate true coagulase-negative staphylococcal (CoNS) bacteremia from contamination, using pulsed-field gel electrophoresis (PFGE) as the reference test.

Design.

The study sample consisted of 79 CoNS isolates recovered from cultures of blood from 38 patients. Medical charts of the patients were reviewed for demographic and clinical information. The relatedness of CoNS strains recovered from 2 or more successive blood cultures was analyzed by PFGE. Patients from whom similar strains were recovered were assumed to have true bacteremia, whereas patients from whom different strains were recovered were considered to have contaminated blood cultures. The clinical criteria comprised Centers for Disease Control and Prevention (CDC) surveillance definitions for bloodstream infection (BSI), as well as an alternative criterion based on the presence of fever, the presence of leukocytosis, the absence of another recognized infection, and the recovery of CoNS from 2 or more successive blood cultures.

Results.

Nineteen (50%) of the 38 patients had bacteremia due to similar strains; the remaining patients had bacteremia due to different strains. Criterion 2a of the CDC definition for BSI had a sensitivity of 100% and a specificity of 31.6% for distinguishing between true bacteremia and contamination. CDC criterion 2b had a sensitivity of 78.9% and a specificity of 52.6%.

Conclusions.

Molecular typing correlated poorly with the clinical criteria for true bacteremia. In view of the limited applicability of clinical criteria, more studies are needed to improve them. Periodic cross-sectional studies based on PFGE findings might be useful to estimate local contamination rates in an institution, which in turn can be used to improve the accuracy of the clinical diagnosis of bacteremia.

Type
Original Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Huebner, J, Goldmann, DA. Coagulase-negative staphylococci: role as pathogens. Ann Rev Med 1999;50:223236.CrossRefGoogle ScholarPubMed
2. Diekema, DJ, Pfaller, MA, Schmitz, FJ, et al. Survey of infections due to Staphylococcus species: frequency of occurrence and antimicrobial susceptibility of isolates collected in the United States, Canada, Latin America, Europe, and the Western Pacific region for the SENTRY Antimicrobial Surveillance Program, 1997-1999. Clin Infect Dis 2001;32(suppl 2):S114S132.Google Scholar
3. Martin, MA, Pfaller, MA, Wenzel, RP. Coagulase-negative staphylococcal bacteremia: mortality and hospital stay. Ann Intern Med 1989;110:916.Google Scholar
4. Thylefors, JD, Harbarth, S, Pittet, D. Increasing bacteremia due to coagulase-negative staphylococci: fiction or reality? Infect Control Hosp Epidemiol 1998;19:581589.Google Scholar
5. Rupp, ME, Archer, GL. Coagulase-negative staphylococci: pathogens associated with medical progress. Clin Infect Dis 1994;19:231243.Google Scholar
6. Schaberg, DR, Culver, DH, Gaynes, RP. Major trends in the microbial etiology of nosocomial infection. Am J Med 1991;91:72S75S.CrossRefGoogle ScholarPubMed
7. Bates, DW, Goldman, L, Lee, TH. Contaminant blood cultures and resource utilization: the true consequences of false-positive results. JAMA 1991;265:365369.Google Scholar
8. Souvenir, D, Anderson, DE Jr, Palpant, S, et al. Blood cultures positive for coagulase-negative staphylococci: antisepsis, pseudobacteremia, and therapy of patients. J Clin Microbiol 1998;36:19231926.Google Scholar
9. Kirchhoff, LV, Sheagren, JN. Epidemiology and clinical significance of blood cultures positive for coagulase-negative Staphylococcus . Infect Control 1985;6:479486.CrossRefGoogle ScholarPubMed
10. Baltimore, RS. Is it real or is it a contaminant? A guide to the interpretation of blood culture results. Am J Dis Child 1987;141:241242.Google Scholar
11. Bates, DW, Lee, TH. Rapid classification of positive blood cultures: prospective validation of a multivariate algorithm. JAMA 1992;267:19621966.Google Scholar
12. Herwaldt, LA, Geiss, M, Kao, C, Pfaller, MA. The positive predictive value of isolating coagulase-negative staphylococci from blood cultures. Clin Infect Dis 1996;22:1420.Google Scholar
13. Khatib, R, Riederer, KM, Clark, JA, Khatib, S, Briski, LE, Wilson, FM. Coagulase-negative staphylococci in multiple blood cultures: strain re-latedness and determinants of same-strain bacteremia. J Clin Microbiol 1995;33:816820.Google Scholar
14. Davenport, DS, Massanari, RM, Pfaller, MA, Bale, MJ, Streed, SA, Hierholzer, WJ Jr. Usefulness of a test for slime production as a marker for clinically significant infections with coagulase-negative staphylococci. J Infect Dis 1986;153:332339.Google Scholar
15. Beekmann, SE, Diekema, DJ, Doern, GV. Determining the clinical significance of coagulase-negative staphylococci isolated from blood cultures. Infect Control Hosp Epidemiol 2005;26:559566.Google Scholar
16. O'Grady, NP, Alexander, M, Dellinger, EP, et al. Guidelines for the prevention of intravascular catheter-related infections. Centers for Disease Control and Prevention. MMWR Recomm Rep 2002;51:129.Google Scholar
17. Tokars, JI. Predictive value of blood cultures positive for coagulase-negative staphylococci: implications for patient care and health care quality assurance. Clin Infect Dis 2004;39:333341.Google Scholar
18. Weinstein, MP, Reiler, LB, Murphy, JR, Lichtenstein, KA. The clinical significance of positive blood cultures: a comprehensive analysis of 500 episodes of bacteremia and fungemia in adults. I. Laboratory and epidemiologic observations. Rev Infect Dis 1983;5:3553.CrossRefGoogle ScholarPubMed
19. Tenover, FC, Arbeit, RD, Goering, RV, et al. Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis: criteria for bacterial strain typing. J Clin Microbiol 1995;33:22332239.Google Scholar
20. Surdulescu, S, Utamsingh, D, Shekar, R. Phlebotomy teams reduce blood-culture contamination rate and save money. Clin Perform Qual Health Care 1998;6:6062.Google ScholarPubMed
21. CDC. Recommendations for preventing the spread of vancomycin resistance. Recommendations of the Hospital Infection Control Practices Advisory Committee (HICPAC). MMWR Recomm Rep 1995;44(RR-12): 113.Google Scholar
22. CDC. Update: Staphylococcus aureus with reduced susceptibility to vancomycin-United States, 1997. MMWR Morb Mortal Wkly Rep 1997;46:813815.Google Scholar
23. CDC. Staphylococcus aureus resistant to vancomycin-United States, 2002. MMWR Morb Mortal Wkly Rep 2002;51:565567.Google Scholar
24. Archer, GL. Coagulase-negative staphylococci in blood cultures: the clinician's dilemma. Infect Control 1985;6:477478.CrossRefGoogle ScholarPubMed
25. Khatib, R. Lack of predictive value of isolating coagulase-negative staphylococci from blood cultures. Clin Infect Dis 1996;23:412.CrossRefGoogle ScholarPubMed
26. Johnson, JR. Defining true bacteremia due to coagulase-negative staphylococci. Clin Infect Dis 1996;23:413414.Google Scholar
27. Reiman, DA, Falkow, S. A molecular perspective of microbial pathogenicity. In: Mandeli, GL, Bennett, JE, Dolin, R, eds. Mandeli, Douglas and Bennett's Principles and Practice of Infectious Diseases. 6th ed. Philadelphia: Elsevier Churchill Livingstone; 2005:314.Google Scholar
28. Sharma, M, Riederer, K, Johnson, LB, Khatib, R. Molecular analysis of coagulase-negative Staphylococcus isolates from blood cultures: prevalence of genotypic variation and polyclonal bacteremia. Clin Infect Dis 2001;33:13171323.Google Scholar
29. Van Wijngaerden, E, Peetermans, WE, Van Lierde, S, Van Eldere, J. Polyclonal staphylococcus endocarditis. Clin Infect Dis 1997;25:6971.Google Scholar
30. Seo, SK, Venkataraman, L, DeGirolami, PC, Samore, MH. Molecular typing of coagulase-negative staphylococci from blood cultures does not correlate with clinical criteria for true bacteremia. Am J Med 2000;109:697704.Google Scholar
31. Leibovici, L, Gransden, WR, Eykyn, SJ, et al. Clinical index to predict bacteraemia caused by staphylococci. J Intern Med 1993;234:8389.Google Scholar
32. Ponce de Leon, S, Wenzel, RP. Hospital-acquired bloodstream infections with Staphylococcus epidermidis: review of 100 cases. Am J Med 1984;77:639644.Google Scholar