What are the best empirical antibiotics for a possible central line (central venous catheter) infection?

Best Empirical Antibiotics for Possible Central Line Infection

For suspected central line infections, empirical therapy should begin with vancomycin for gram-positive coverage, plus appropriate gram-negative coverage based on severity of illness and local resistance patterns. 1

Initial Empirical Antibiotic Selection

Gram-Positive Coverage

• Vancomycin is the recommended first-line empirical treatment for suspected central line-related bloodstream infections before blood culture results are available 1, 2
• Daptomycin can be used as an alternative in patients with higher risk for nephrotoxicity or in settings with high prevalence of MRSA strains with vancomycin MIC ≥2 μg/ml 1, 2
• Linezolid should NOT be used for empirical therapy in patients with suspected but not proven bacteremia 1

Gram-Negative Coverage

• For patients with severe symptoms (sepsis, neutropenia), add empirical anti-gram-negative coverage with one of the following 1:
  • Fourth-generation cephalosporins 1
  • Carbapenems 1
  • β-lactam/β-lactamase combinations with or without an aminoglycoside 1

Special Considerations

• For critically ill patients with femoral catheters, empirical therapy should include coverage for gram-negative bacilli AND Candida species in addition to gram-positive coverage 1
• For neutropenic patients, severely ill patients with sepsis, or patients known to be colonized with multidrug-resistant organisms, consider empirical combination antibiotic coverage for MDR gram-negative bacilli, such as Pseudomonas aeruginosa 1
• Selection of antibiotics should be guided by local antimicrobial susceptibility testing data and institutional patterns 1

Empirical Antifungal Therapy

• Empirical therapy for suspected catheter-related candidemia is indicated for septic patients with any of the following risk factors 1, 2:

  • Total parenteral nutrition 1, 2
  • Prolonged use of broad-spectrum antibiotics 1, 2
  • Hematological malignancy 1, 2
  • Receipt of bone marrow or solid organ transplant 1, 2
  • Femoral catheterization 1
  • Colonization with Candida species at multiple sites 1, 2

• For empirical treatment of suspected catheter-related candidemia:

  • Use an echinocandin (caspofungin, micafungin, anidulafungin) as first-line therapy in critically ill patients 1
  • Fluconazole can be used if the patient is clinically stable, has had no exposure to azoles in the previous 3 months, and is in a healthcare setting where the risk of C. krusei or C. glabrata infection is very low 1

Diagnostic Approach Before Starting Antibiotics

• Blood cultures should be obtained before starting antibiotic therapy 1:
  • Collect paired blood samples from the catheter and from a peripheral vein 1
  • If peripheral vein cultures are not possible, draw two blood samples at different times from different catheter lumens 1
  • Use alcohol, iodine tincture, or alcoholic chlorhexidine for skin preparation before collection 1

Duration of Therapy and Catheter Management

Catheter Removal Indications

• Long-term catheters should be removed in patients with CRBSI associated with 1, 2:
  • Severe sepsis 1, 2
  • Suppurative thrombophlebitis 1, 2
  • Endocarditis 1, 2
  • Tunnel infection or port abscess 1, 2
  • Bloodstream infection that continues despite 48-72h of adequate coverage 1
  • Infections due to S. aureus, P. aeruginosa, fungi, or mycobacteria 1

Treatment Duration

• For most cases, 10-14 days of treatment is recommended after resolution of signs of infection 1, 2
• For persistent fungemia or bacteremia after catheter removal (>72h), 4-6 weeks of treatment is recommended 1
• For complications such as endocarditis or suppurative thrombophlebitis, 4-6 weeks of treatment is recommended 1

Catheter Salvage Approach

• If catheter salvage is attempted, antibiotic lock therapy (ALT) should be used in addition to systemic therapy 1, 2
• ALT treatment duration should be 7-14 days with dwell time ≥12 hours (minimum 8 hours per day) 1, 2
• For patients with CRBSI where catheter salvage is attempted, additional blood cultures should be obtained, and the catheter should be removed if blood cultures remain positive after 72 hours of appropriate therapy 1

Common Pitfalls and Caveats

• Inadequate empirical antibiotic coverage is associated with increased mortality in patients with sepsis 3
• However, unnecessarily broad empirical antibiotic therapy is also associated with higher mortality and may encourage the emergence of resistant bacteria 4, 3
• When blood culture results become available, de-escalation of the initial broad regimen is important to minimize the risk of antimicrobial resistance development 5
• The diagnosis of central line infection should be considered only after other causes of fever have been ruled out, especially in patients with long-term catheterization 6
• Skin organisms (coagulase-negative staphylococci and S. aureus) are the most common pathogens in central line infections, but gram-negative coverage is essential in critically ill patients 6