Molecular epidemiology of catheter-related bloodstream infections caused by coagulase-negative staphylococci in haematological patients with neutropenia

Epidemiol Infect. 2004 Oct;132(5):921-5. doi: 10.1017/s0950268804002584.

Abstract

Catheter-related bloodstream infection (CRBSI) caused by coagulase-negative staphylococci (CNS) is common in haematological patients with febrile neutropenia. As the clinical signs of CRBSI are usually scarce and it is difficult to differentiate from blood culture contamination, we tried to confirm CRBSI by molecular typing of CNS isolated from paired blood cultures (one from a peripheral vein and another from the central venous catheter hub). Blood cultures were positive in 59 (36%) out of 163 patients. CNS were isolated in 24 (40%) patients; in 14 from paired blood cultures (28 isolates) and in 10 from a single blood culture. CNS from paired blood cultures were identified as Staphylococcus epidermidis. Antimicrobial susceptibility was determined and bacteria were typed by pulsed-field gel electrophoresis (PFGE) of bacterial genomic DNA. In 13 patients, the antibiotic susceptibility of isolates was identical. The PFGE patterns from paired blood cultures were identical or closely related in 10 patients, thus confirming the presence of CRBSI. In the remaining four patients they were unrelated, and suggested a mixed infection or contamination. Since CNS isolates from three patients had identical PFGE patterns, they were probably nosocomially spread amongst them.

MeSH terms

  • Anti-Infective Agents / pharmacology
  • Anti-Infective Agents / therapeutic use
  • Bacteremia / blood
  • Bacteremia / drug therapy
  • Bacteremia / epidemiology*
  • Bacteremia / etiology
  • Catheters, Indwelling / adverse effects*
  • Cross Infection / blood
  • Cross Infection / drug therapy
  • Cross Infection / epidemiology*
  • Cross Infection / etiology
  • DNA, Bacterial / analysis
  • Drug Resistance, Bacterial
  • Electrophoresis, Gel, Pulsed-Field
  • Female
  • Humans
  • Male
  • Microbial Sensitivity Tests
  • Neutropenia*
  • Polymerase Chain Reaction
  • Slovenia / epidemiology
  • Staphylococcal Infections / blood
  • Staphylococcal Infections / drug therapy
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / etiology
  • Staphylococcus epidermidis / drug effects
  • Staphylococcus epidermidis / genetics*
  • Staphylococcus epidermidis / isolation & purification

Substances

  • Anti-Infective Agents
  • DNA, Bacterial