Skip to main content
Log in

Coagulase-negative staphylococci in very-low-birth-weight infants: inability of genetic markers to distinguish invasive strains from blood culture contaminants

  • Article
  • Published:
European Journal of Clinical Microbiology and Infectious Diseases Aims and scope Submit manuscript

Abstract

Selected coagulase-negative staphylococci from the blood of very-low-birth-weight infants in the Neonatal Intensive Care Unit at the Royal Women’s Hospital, Melbourne, collected over a 5-year period were examined. Isolates were classified as invasive or contaminants, speciated, typed by pulsed-field gel electrophoresis, and examined for biofilm genes (icaA, icaC, and icaD), adhesion genes (atlE, fbe), and the number of copies of IS256. Of the 24 isolates studied, there were 13 contaminants and 11 invasive isolates. The collection included 15 Staphylococcus epidermidis, eight Staphylococcus capitis, and one each of Staphylococcus warneri and Staphylococcus haemolyticus. Two small clusters of S. epidermidis that belonged to the same molecular type were identified. All S. capitis isolates belonged to the same molecular type or subtype, suggesting that a particular clone was circulating in the unit. There was no significant difference in the species found, the presence of icaA, icaC, icaD, atlE, or fbe, or the number of copies of IS256 between invasive isolates and contaminants. A series of nasal isolates from nonhospitalized adults differed from hospital isolates in the absence of IS256 and the low prevalence of icaC. There was no evidence of IS256-mediated insertion into ica genes as a mechanism of phase variation. These findings suggest that contaminants and invasive isolates derived from the same pool of hospital strains capable of causing sepsis in compromised hosts and that other mechanisms of phase variation exist, apart from IS256 insertion into ica genes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3

Similar content being viewed by others

References

  1. Stoll BJ, Hansen N, Fanaroff AA, Wright LL, Carlo WA, Ehrenkranz RA, Lemons JA, Donovan EF, Stark AR, Tyson JE, Oh W, Bauer CR, Korones SB, Shankaran S, Laptook SAR, Stevenson DK, Papile LA, Poole WK (2002) Late-onset sepsis in very low birth weight neonates: the experience of the NICHD Neonatal Research Network. Pediatrics 110:285–291

    Article  PubMed  Google Scholar 

  2. Kaufman D, Fairchild KD (2004) Clinical microbiology of bacterial and fungal sepsis in very low birth weight babies. Clin Microbiol Rev 17:638–680

    Article  PubMed  Google Scholar 

  3. Bialkowska-Hobrzanska H, Jaskot D, Hammerberg O (1993) Molecular characterization of the coagulase-negative staphylococcal surface flora of premature neonates. J Gen Microbiol 139:2939–2944

    PubMed  CAS  Google Scholar 

  4. Björkqvist MB, Söderquist O, Törnqvist E, Sjöberg L, Fredlund H, Kühn I, Colque-Navarro P, Schollin J (2002) Phenotypic and genotypic characterisation of blood isolates of coagulase-negative staphylococci in the newborn. APMIS 110:332–339

    Article  PubMed  Google Scholar 

  5. Burnie JP, Naderi-Nasab M, Loudon KW, Matthew RC (1997) An epidemiological study of blood culture isolates of coagulase-negative staphylococci demonstrating hospital-acquired infection. J Clin Microbiol 35:1746–1750

    PubMed  CAS  Google Scholar 

  6. Huebner JG, Pier B, Maslow JN, Muller, Shiro EH, Parent M, Kropec A, Arbei RD, Goldmann DA (1994) Endemic nosocomial transmission of Staphylococcus epidermidis bacteremia isolates in a neonatal intensive care unit over 10 years. J Infect Dis 169:526–531

    PubMed  CAS  Google Scholar 

  7. Low DE, Schmidt BK, Kirpalani HM, Moodie R, Kreiswirth B, Matlow A, Ford-Jones EL (1992) An endemic strain of Staphylococcus haemolyticus colonizing and causing bacteremia in neonatal intensive care unit patients. Pediatrics 89:696–700

    PubMed  CAS  Google Scholar 

  8. Raimundo O, Heussler H, Bruhn JB, Suntrarachun S, Kelly N, Deighton MA, Garland SM (2002) Molecular epidemiology of coagulase-negative staphylococcal bacteraemia in a newborn intensive care unit. J Hosp Infect 51:33–42

    Article  CAS  Google Scholar 

  9. Vermont CL, Hartwig NG, Fleer A, de Man P, Verbrugh H, van den Anker J, de Groot R, van Belkum A (1998) Persistence of clones of coagulase-negative staphylococci among premature neonates in neonatal intensive care units: two-center study of bacterial genotyping and patient risk factors. J Clin Microbiol 36:2485–2490

    PubMed  CAS  Google Scholar 

  10. Villari P, Sarnataro C, Iacuzio L (2000) Molecular epidemiology of Staphylococcus epidermidis in a neonatal intensive care unit over a three-year period. J Clin Microbiol 38:1740–1746

    PubMed  CAS  Google Scholar 

  11. Vuong C, Otto M (2002) Staphylococcus epidermidis infections. Microbes Infect 4:481–489

    Article  PubMed  Google Scholar 

  12. Vuong C, Kocianova S, Voyich JM, Yao Y, Fischer ER, DeLeo FR, Otto M (2004) A crucial role for exopolysaccharide modification in bacterial biofilm formation, immune evasion and virulence. J Biol Chem 279:54881–54886

    Article  PubMed  CAS  Google Scholar 

  13. de Silva GD, Kantzanou M, Justice A, Massey RC, Wilkinson AR, Day NP, Peacock SJ (2002) The ica operon and biofilm production in coagulase-negative staphylococci associated with carriage and disease in a neonatal intensive care unit. J Clin Microbiol 40:382–388

    Article  PubMed  Google Scholar 

  14. Cho S-H, Naber K, Hacker J, Ziebuhr W (2002) Detection of the icaADBC gene cluster and biofilm formation in Staphylococcus epidermidis isolates from catheter-related urinary tract infections. Int J Antimicrob Agents 19:570–575

    Article  PubMed  CAS  Google Scholar 

  15. Ziebuhr W, Krimmer V, Rachid S, Lössner I, Götz F, Hacker J (1999) A novel mechanism of phase variation of virulence in Staphylococcus epidermidis: evidence for control of the polysaccharide intercellular adhesin synthesis by alternating insertion and excision of the insertion sequence element IS256. Mol Microbiol 32:345–356

    Article  PubMed  CAS  Google Scholar 

  16. Kozitskaya S, Cho S-H, Dietrich K, Marre R, Naber K, Ziebuhr W (2004) The bacterial insertion sequence element IS256 occurs preferentially in nosocomial Staphylococcus epidermidis isolates: association with biofilm formation and resistance to aminoglycosides. Infect Immun 72:1210–1215

    Article  PubMed  CAS  Google Scholar 

  17. Rohde H, Knobloch JH, Horstkotte MA, Mack D (2001) Correlation of biofilm expression types of Staphylococcus epidermidis with polysaccharide intercellular adhesin synthesis: evidence for involvement of icaADBC genotype-independent factors. Med Microbiol Immunol 190:105–112

    PubMed  CAS  Google Scholar 

  18. National Committee for Clinical Laboratory Standards (2003) Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. Approved standard M7-A6. NCCLS, Wayne, Pennsylvania

    Google Scholar 

  19. Smith CL, Cantor CR (1987) Purification, specific fragmentation, and separation of large DNA molecules. Methods Enzymol 155:449–467

    Article  PubMed  CAS  Google Scholar 

  20. Tenover FC, Arbeit RD, Goering RV, Mickelsen PA, Murray BE, Persing DH, Swaminathan B (1995) Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis: criteria for bacterial strain typing. J Clin Microbiol 33:2233–2239

    PubMed  CAS  Google Scholar 

  21. Unal S, Hoskins J, Flokowitsch JE, Wu CY, Preston DA, Skatrud PL (1992) Detection of methicillin-resistant staphylococci by using the polymerase chain reaction. J Clin Microbiol 30:1685–1691

    PubMed  CAS  Google Scholar 

  22. Handke LD, Conlon KM, Slater SR, Elbaruni S, Fitzpatrick F, Humphreys H, Giles WP, Rupp ME, Fey PD, O’Gara JP (2004) Genetic and phenotypic analysis of biofilm phenotypic variation in multiple Staphylococcus epidermidis isolates. J Med Microbiol 53:367–374

    Article  PubMed  CAS  Google Scholar 

  23. Freeman D, Falkiner JFR, Keane CT (1989) New method for detecting slime production by coagulase negative staphylococci. J Clin Pathol 42:872–874

    Article  PubMed  CAS  Google Scholar 

  24. Heilmann C, Götz F (1998) Further characterization of Staphylococcus epidermidis transposon mutants deficient in primary attachment or intercellular adhesion. Zentralbl Bakteriol 287:69–83

    PubMed  CAS  Google Scholar 

  25. Deighton MA, Capstick, Domalewski JE, van Nguyen T (2001) Methods for studying biofilms produced by Staphylococcus epidermidis. Methods Enzymol 336:177–195

    PubMed  CAS  Google Scholar 

  26. Knobloch JK, Horstkotte MA, Rohde H, Kaulfers PM, Mack D (2002) Alcoholic ingredients in skin disinfectants increase biofilm expression of Staphylococcus epidermidis. J Antimicrob Chemother 49:683–687

    Article  PubMed  CAS  Google Scholar 

  27. Van Der Zwet WC, Debets-Ossenkopp YJ, Reinders E, Kapi M, Savelkoul PH, Van Elburg RM, Hiramatsu K, Vandenbroucke-Grauls CM (2002) Nosocomial spread of a Staphylococcus capitis strain with heteroresistance to vancomycin in a neonatal intensive care unit. J Clin Microbiol 40:2520–2525

    Article  CAS  Google Scholar 

  28. Wang S-M, Liu C-C, Tseng H-W, Yang Y-J, Lin C-H, Huang A-Y, Wu Y-H (1999) Staphylococcus capitis bacteremia of very low birth weight premature infects at neonatal intensive care units: clinical significance and antimicrobial susceptibility. J Immunol Infect 32:26–32

    CAS  Google Scholar 

  29. Conlon KM, Humphreys H, O’Gara JP (2004). Inactivations of rsbU and sarA by IS256 represent novel mechanisms of biofilm phenotypic variation in Staphylococcus epidermidis. J Bacteriol 186:6208–6219

    Article  PubMed  CAS  Google Scholar 

  30. Klug D, Wallet F, Kacet S, Courcol RJ (2003) Involvement of adherence and adhesion Staphylococcus epidermidis genes in pacemaker lead-associated infections. J Clin Microbiol 41:3348–3350

    Article  PubMed  Google Scholar 

  31. Frebourg NB, Lefebvre S, Baert S, Lemeland JF (2000) PCR-based assay for discrimination between invasive and contaminating Staphylococcus epidermidis strains. J Clin Microbiol 38:877–880

    PubMed  CAS  Google Scholar 

  32. Rohde H, Kalitzky M, Kröger N, Scherpe S, Horstkotte MA, Knobloch JKM, Zander AR, Mack D (2004) Detection of virulence-associated genes not useful for discriminating between invasive and commensal Staphylococcus epidermidis strains from a bone marrow transplant unit. J Clin Microbiol 42:5614–5619

    Article  PubMed  CAS  Google Scholar 

  33. Arciola CR, Campoccia D, Gamberini S, Rizzi S, Donati ME, Baldassarri L, Montanaro L (2004) Search for the insertion element IS256 within the ica locus of Staphylococcus epidermidis clinical isolates collected from biomaterial-associated infections. Biomaterials 25:4117–4125

    Article  PubMed  CAS  Google Scholar 

  34. Nilsson M, Frykberg L, Flock JI, Pei L, Lindberg M, Guss B (1998) A fibrinogen-binding protein of Staphylococcus epidermidis. Infect Immun 66:2666–2673

    PubMed  CAS  Google Scholar 

Download references

Acknowledgement

This work was partly supported by a grant from the Faculty of Life Sciences, RMIT University, Bundoora, Victoria, Australia.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to M. Deighton.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bradford, R., Abdul Manan, R., Daley, A.J. et al. Coagulase-negative staphylococci in very-low-birth-weight infants: inability of genetic markers to distinguish invasive strains from blood culture contaminants. Eur J Clin Microbiol Infect Dis 25, 283–290 (2006). https://doi.org/10.1007/s10096-006-0130-2

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10096-006-0130-2

Keywords

Navigation