What is the common organism isolated from an infected central catheter in the femoral vein, specifically Staphylococcus (Staph) aureus or Staphylococcus (Staph) epidermidis?

From the Guidelines

The most common organism isolated from infected central catheters in the femoral vein is Staphylococcus epidermidis (option C). While Staphylococcus aureus is also frequently isolated from catheter-related bloodstream infections, S. epidermidis is more commonly found as it is part of the normal skin flora and readily forms biofilms on catheter surfaces, as noted in a recent study 1. These biofilms allow the bacteria to adhere to and colonize the catheter material, making them difficult to eradicate. Femoral vein catheters are particularly susceptible to infection due to their placement in the groin area, which has higher bacterial colonization compared to other insertion sites. Some key points to consider in the management and prevention of catheter-related infections include:

• The use of sterile gloves and alcohol-containing chlorhexidine for skin antisepsis before insertion and during dressing change 1
• Maximal sterile barrier precautions, including the use of a cap, mask, gown, and sterile full-body drape 1
• Avoiding the use of systemic antimicrobial prophylaxis 1
• Preferring an infraclavicular rather than a supraclavicular or groin exit site 1 Management of catheter-related infections typically involves catheter removal when possible, along with appropriate antibiotic therapy based on culture results, usually with vancomycin empirically while awaiting susceptibility testing, as recommended in guidelines for the management of intravascular catheter-related infections 1. Prevention strategies include strict adherence to aseptic technique during insertion, proper site care, and removal of catheters as soon as they are no longer needed.

From the Research

Common Organisms Isolated from Infected Central Catheters

• The most common organisms isolated from infected central catheters include:
  • Staphylococcus epidermidis
  • Staphylococcus aureus
  • Candida species
  • Gram-negative bacteria such as Pseudomonas aeruginosa and Enterobacteriaceae 2, 3

Specific Organisms Isolated from Femoral Vein Catheters

• Studies have shown that the infection rate of femoral vein catheters is higher compared to subclavian vein catheters 2
• The most common organisms isolated from infected femoral vein catheters include:
  • Staphylococcus epidermidis
  • Staphylococcus aureus
  • Candida species 2, 3

Comparison of Staphylococcus epidermidis and Staphylococcus aureus

• Both Staphylococcus epidermidis and Staphylococcus aureus are common causes of central line-associated bloodstream infections 4, 5
• Staphylococcus epidermidis is a common commensal organism on human skin, while Staphylococcus aureus is a more virulent organism that can cause a range of infections 4, 6

Risk Factors for Central Line-Associated Bloodstream Infections

• The risk of central line-associated bloodstream infections is increased with:
  • Longer indwelling times
  • Femoral vein catheters
  • Poor catheter care and maintenance 2, 3