What is the treatment for a Staphylococcus (Staph) coagulase-negative line infection?

Treatment of Coagulase-Negative Staphylococcus Line Infection

For uncomplicated coagulase-negative staphylococcal catheter-related bloodstream infection (CRBSI), treat with systemic antibiotics for 5-7 days if the catheter is removed, or 10-14 days combined with antibiotic lock therapy if the catheter is retained. 1

Initial Diagnostic Confirmation

• Confirm true infection versus contamination by obtaining blood cultures from both the catheter and a peripheral vein—coagulase-negative staphylococci are the most common blood culture contaminant but also the most common cause of CRBSI. 1
• A differential time to positivity (DTTP) of ≥2 hours between catheter and peripheral cultures is highly sensitive and specific for catheter-related bacteremia. 1
• Multiple positive blood cultures from different sites strongly indicate true CRBSI rather than contamination. 1

Catheter Management Decision

Remove the catheter if:

• Severe sepsis or systemic inflammatory response syndrome is present 1
• Suppurative thrombophlebitis or endocarditis is suspected 1
• Tunnel infection or port abscess exists 1
• Bacteremia persists despite 48-72 hours of appropriate antibiotic therapy 1
• The patient has concurrent fungal or mycobacterial infection 1

Attempt catheter salvage if:

• The patient is clinically stable without systemic toxicity 1
• No tunnel or pocket infection is present 1
• The catheter is essential with no alternative venous access 1
• The infection is uncomplicated without metastatic complications 1

Antibiotic Selection

Empiric Therapy:

• Start with vancomycin administered through the infected line when possible to cover Gram-positive organisms including methicillin-resistant strains. 1
• Vancomycin dosing: 15-20 mg/kg IV every 8-12 hours for adults 1
• Teicoplanin is a useful alternative as it can be administered once daily as a line lock. 1

Definitive Therapy (after susceptibility results):

• Adjust antibiotics based on antimicrobial susceptibility testing 1
• For methicillin-susceptible strains, consider switching to a penicillinase-resistant penicillin or first-generation cephalosporin 2
• Continue vancomycin for methicillin-resistant strains 2, 3

Treatment Duration

If catheter is removed:

• 5-7 days of systemic antibiotics for uncomplicated infection 1
• Alternatively, observation without antibiotics is acceptable if the patient has no intravascular or orthopedic hardware, the catheter is removed, and follow-up blood cultures (off antibiotics) confirm clearance of bacteremia 1

If catheter is retained:

• 10-14 days of systemic antibiotics combined with antibiotic lock therapy 1
• Antibiotic lock therapy should have a dwell time of ≥12 hours (minimum 8 hours per day) and should not exceed 48 hours before reinstallation 1

If complications develop:

• 4-6 weeks of treatment if positive cultures persist 72 hours after catheter removal or if endocarditis or suppurative thrombophlebitis is present 1
• 6-8 weeks if osteomyelitis develops 1

Special Considerations

Staphylococcus lugdunensis:

• Manage similarly to S. aureus CRBSI due to its propensity for endocarditis and metastatic infections—this requires catheter removal and 4-6 weeks of antimicrobial therapy. 1

Febrile Neutropenia Context:

• In neutropenic patients, catheter retention was successful in 46% of neonatal cases and 93% of adult cases when treated appropriately, though catheter retention is a significant risk factor for recurrence. 1
• The re-infection rate over 4 months was only 8% in successfully treated cases. 1

Follow-up Monitoring:

• Obtain repeat blood cultures 2-4 days after initiating therapy to document clearance of bacteremia 1
• Assess for metastatic complications including endocarditis, especially if fever or bacteremia persists beyond 72 hours 1

Common Pitfalls to Avoid

• Do not assume contamination without obtaining multiple blood culture sets—coagulase-negative staphylococci cause genuine CRBSI despite being common contaminants. 1
• Do not remove catheters prematurely in stable patients with essential venous access—salvage rates are high with appropriate antibiotic therapy. 1
• Do not use inadequate treatment duration—infections with retained catheters require 10-14 days, not the 5-7 days used when catheters are removed. 1
• Do not fail to use antibiotic lock therapy when attempting catheter salvage—systemic antibiotics alone have lower success rates. 1
• Do not overlook increasing glycopeptide resistance—teicoplanin-non-susceptible strains with inducible vancomycin resistance have emerged and require vigilant surveillance. 3