Treatment of Catheter-Related Bloodstream Infection (CRBSI) due to Enterobacter cloacae
For CRBSI due to Enterobacter cloacae, remove the catheter immediately (short-term catheters) or promptly (long-term catheters), initiate empirical IV therapy with a fourth-generation cephalosporin, carbapenem, or β-lactam/β-lactamase combination based on local susceptibility patterns, and treat for 7-14 days after catheter removal if uncomplicated. 1
Catheter Management
Catheter removal is mandatory for successful treatment:
- Short-term catheters: Remove immediately upon diagnosis of gram-negative CRBSI 1
- Long-term catheters: Remove promptly, especially if severe sepsis, persistent bacteremia >72 hours despite appropriate therapy, or suppurative thrombophlebitis is present 1
- Catheter salvage should NOT be attempted for E. cloacae CRBSI, as gram-negative bacilli require catheter removal for cure 1
Empirical Antibiotic Selection
Choose empirical therapy based on local antibiogram and severity of illness:
- Fourth-generation cephalosporin (e.g., cefepime) 1
- Carbapenem (e.g., meropenem, imipenem) 1
- β-lactam/β-lactamase combination (e.g., piperacillin-tazobactam) 1
- With or without an aminoglycoside for critically ill or septic patients 1
For critically ill patients, neutropenic patients, or those with known MDR colonization: Use combination therapy with two different classes of gram-negative agents until susceptibilities return, then de-escalate 1
Definitive Therapy
Once susceptibilities are available:
- De-escalate to the narrowest-spectrum agent with activity against E. cloacae 1
- E. cloacae typically produces AmpC β-lactamases, making third-generation cephalosporins unreliable 2
- Preferred agents include fourth-generation cephalosporins (if susceptible), carbapenems, or fluoroquinolones based on susceptibility testing 1
Treatment Duration
Standard duration depends on clinical response:
- 7-14 days for uncomplicated CRBSI after catheter removal 1
- 4-6 weeks if persistent bacteremia >72 hours after catheter removal, endocarditis, or suppurative thrombophlebitis develops 1
- 6-8 weeks if osteomyelitis is present 1
Monitoring and Follow-up
Obtain follow-up blood cultures:
- Draw cultures 72 hours after initiating appropriate therapy 1
- If cultures remain positive at 72 hours, remove any retained catheter and evaluate for endovascular infection or metastatic complications 1
- Perform transesophageal echocardiography if bacteremia persists >72 hours or signs of endocarditis develop 1
Critical Pitfalls to Avoid
Do not use third-generation cephalosporins as definitive therapy: E. cloacae produces inducible AmpC β-lactamases that confer resistance to third-generation cephalosporins even when initial susceptibility testing suggests susceptibility 2
Do not attempt catheter salvage: Unlike coagulase-negative staphylococci, gram-negative CRBSI requires catheter removal for cure 1
Do not use oral antibiotics: Active CRBSI requires intravenous therapy due to the severity of infection and need for high serum antibiotic concentrations 3
Do not delay catheter removal in septic patients: Antibiotic therapy alone without catheter removal results in 5-fold higher treatment failure rates 3