What are the recommended antibiotics for treating Enterobacter cloacae infections?

Recommended Antibiotics for Enterobacter cloacae Infections

Carbapenems are the first-line treatment for Enterobacter cloacae infections, with meropenem and imipenem being particularly effective against this organism. 1

First-line Treatment Options

• Carbapenems: Meropenem and imipenem are highly effective against E. cloacae, including many multidrug-resistant strains 1

  • Meropenem is preferred over imipenem for most E. cloacae infections due to slightly better efficacy profile 2
  • Dosing: Standard dosing for serious infections (e.g., meropenem 1g IV q8h or imipenem 500mg IV q6h) 3

• Fourth-generation cephalosporins: Cefepime can be effective if Extended-Spectrum Beta-Lactamase (ESBL) is absent 1, 4

  • Cefepime has shown efficacy even against some ceftazidime-resistant strains of E. cloacae 4

Treatment for Resistant Strains

For carbapenem-resistant E. cloacae (part of CRE - Carbapenem-Resistant Enterobacterales):

• Ceftazidime-avibactam: Recommended as first-line for KPC-producing CRE with 95% susceptibility 1, 5

  • Dosing: 2.5g IV q8h infused over 3 hours 1, 6

• Meropenem-vaborbactam: Effective alternative with 92% susceptibility against CRE 1, 5

  • Dosing: 4g IV q8h 1

• Imipenem-cilastatin-relebactam: Another option for CRE with 84% susceptibility 1, 5

  • Dosing: 1.25g IV q6h 1

• Cefiderocol: Effective against 92% of CRE isolates, including some metallo-β-lactamase producers 1, 5

Treatment Based on Infection Site

For Bloodstream Infections (BSI)

• Carbapenem (meropenem or imipenem) is first-line therapy 1
• For carbapenem-resistant strains, ceftazidime-avibactam is recommended 1
• Polymyxin-based combination therapy may be considered for highly resistant strains 1

For Complicated Urinary Tract Infections (cUTI)

• Carbapenems are first-line for susceptible strains 1
• For carbapenem-resistant strains:
  • Ceftazidime-avibactam 2.5g IV q8h 1
  • Meropenem-vaborbactam 4g IV q8h 1
  • Single-dose aminoglycoside may be considered for simple cystitis 1

For Complicated Intra-abdominal Infections (cIAI)

• Carbapenems remain first-line for susceptible strains 1, 3
• For carbapenem-resistant strains:
  • Ceftazidime-avibactam 2.5g IV q8h plus metronidazole 1, 6
  • Tigecycline 100mg IV loading dose then 50mg IV q12h 1

Important Considerations

• Avoid first and second-generation cephalosporins as they are generally ineffective against Enterobacter infections 1
• Third-generation cephalosporins (like ceftazidime, ceftriaxone) are not recommended due to increased likelihood of resistance development 1, 2
• Combination therapy may be beneficial for severe infections with resistant strains, though evidence is mixed 1
• Prolonged infusion of β-lactams is recommended for pathogens with high minimum inhibitory concentration (MIC) 1
• Infectious disease consultation is highly recommended for managing infections caused by multidrug-resistant organisms 1

Common Pitfalls to Avoid

• Avoid monotherapy with tigecycline for bloodstream infections due to poor plasma concentrations 1
• Avoid third-generation cephalosporins even if initially susceptible, as resistance can rapidly develop during treatment 1, 2
• Don't delay appropriate therapy as this can lead to increased mortality, especially in critically ill patients 3
• Don't forget to adjust dosing based on renal function, particularly for carbapenems and cephalosporins 4
• Consider local resistance patterns when selecting empiric therapy, as resistance profiles can vary significantly by region 7