Treatment of Citrobacter koseri Septicemia

Initial Management

The Society of Critical Care Medicine recommends obtaining appropriate microbiologic cultures before starting antimicrobial therapy, but do not delay antibiotics more than 45 minutes 1
The Intensive Care Society recommends administering IV antimicrobials within one hour of recognition of sepsis or septic shock 2, 3
Initial empiric therapy should include broad-spectrum coverage for all likely pathogens, as recommended by the Infectious Diseases Society of America 2
For septic shock, consider empiric combination therapy using at least two antibiotics of different antimicrobial classes aimed at the most likely bacterial pathogens, as suggested by the American College of Chest Physicians 3

Consider adding an aminoglycoside or fluoroquinolone for combination therapy in septic shock, as recommended by the European Society of Clinical Microbiology and Infectious Diseases 2

For uncomplicated C. koseri septicemia, 7-10 days of antimicrobial therapy is generally adequate, according to the Infectious Diseases Society of America 2, 3
Longer courses (14 days or more) may be appropriate for patients with slow clinical response, undrainable foci of infection, immunologic deficiencies, as recommended by the American College of Physicians 3

Identify and control any source of infection within 12 hours of diagnosis, as recommended by the Society of Critical Care Medicine 3
Remove the catheter in cases of clinical deterioration, persistent bacteremia, or suppurative complications, as suggested by the European Society of Clinical Nutrition and Metabolism 4, 5
Consider antibiotic lock therapy in conjunction with systemic antibiotics for long-term catheters that must be preserved, as recommended by the Infectious Diseases Society of America 6, 7

Reassess antimicrobial regimen daily for potential de-escalation, as recommended by the American College of Chest Physicians 1, 3
Narrow therapy once pathogen identification and susceptibilities are established, as suggested by the European Society of Clinical Microbiology and Infectious Diseases 2, 3
If combination therapy was initiated for septic shock, discontinue within the first few days in response to clinical improvement, as recommended by the Society of Critical Care Medicine 3
Consider procalcitonin levels to support shortening the duration of antimicrobial therapy, as suggested by the American College of Physicians 3

Assess for clinical improvement within 48-72 hours of initiating appropriate antimicrobial therapy, as recommended by the Infectious Diseases Society of America 3
Persistent bacteremia beyond 72 hours suggests inadequate source control, inappropriate antimicrobial selection, or complications, as suggested by the European Society of Clinical Nutrition and Metabolism 5
Monitor inflammatory markers to assess response to therapy, as recommended by the American College of Chest Physicians 8

Delayed initiation of appropriate antimicrobial therapy significantly increases mortality, as reported by the Intensive Care Society 1, 2
Failure to identify and control the source of infection, as emphasized by the Society of Critical Care Medicine 3
Insufficient duration of therapy for complicated infections, as recommended by the American College of Physicians 3