Is cefepime (Cefepime) effective against Escherichia coli (E. coli)?

Cefepime's Effectiveness Against E. coli

Cefepime is effective against Escherichia coli and is specifically FDA-approved for treating urinary tract infections caused by E. coli, including cases with concurrent bacteremia. 1

Spectrum of Activity and Indications

• Cefepime is a fourth-generation cephalosporin with excellent activity against E. coli, inhibiting 90% of isolates at concentrations as low as 0.12 mg/L 2
• The FDA has specifically approved cefepime for uncomplicated and complicated urinary tract infections (including pyelonephritis) caused by E. coli, for both mild-to-moderate and severe infections 1
• Cefepime is also indicated for empiric treatment of febrile neutropenia, where coverage of gram-negative organisms including E. coli is essential 3

Considerations with Resistant E. coli Strains

• For ESBL (Extended-Spectrum Beta-Lactamase)-producing E. coli, cefepime may remain active against AmpC-producing strains 3
• Clinical outcomes with cefepime against ESBL-producing E. coli depend on the minimum inhibitory concentration (MIC):
  • Standard-dose cefepime is reasonable for definitive therapy when the MIC is ≤2 mg/L (CLSI) or ≤1 mg/L (EUCAST) 4
  • Higher doses may be considered for MICs in the 4-8 mg/L range 4
  • Cefepime should be avoided for empiric treatment of suspected ESBL infections 5

Clinical Evidence and Outcomes

• Several retrospective studies have evaluated cefepime versus carbapenems for treating resistant Enterobacterales, with varying results depending on the resistance mechanism 3
• Some studies have found higher mortality with cefepime for ESBL infections, particularly with higher MICs in the susceptible dose-dependent category 3
• A small retrospective study of 13 patients with 15 episodes of infection with ESBL-producing E. coli or K. pneumoniae showed 12 clinical cures, 1 improvement, and 2 failures with cefepime treatment 6

Risk Factors for Cefepime Resistance

• Previous treatment with cefepime (OR = 6.32) 7
• Use of ventilator (OR = 6.25) 7
• Use of catheter (OR = 6.28) 7
• Prolonged hospital stay 7

Clinical Recommendations

• For wild-type, susceptible E. coli infections, cefepime is an excellent choice with high efficacy 1, 2
• For suspected or confirmed ESBL-producing E. coli:
  • Obtain MIC testing before using cefepime for definitive therapy 5
  • Consider alternative agents such as carbapenems if the MIC is >2 mg/L or if the infection is severe 3, 5
  • Monitor clinical response closely if using cefepime for ESBL-producing strains 4

Dosing Considerations

• For uncomplicated or complicated UTIs caused by E. coli:
  • Mild to moderate: 0.5-1g IV every 12 hours for 7-10 days 1
  • Severe: 2g IV every 12 hours for 10 days 1
• Dose adjustment is required for patients with renal impairment 1