Sensitive Antibiotics for Enterobacter cloacae Infections
Carbapenems (meropenem, imipenem-cilastatin, or doripenem) are the preferred first-line agents for serious Enterobacter cloacae complex infections due to their broad spectrum of activity and low resistance rates. 1
First-Line Treatment Options
- Carbapenems are the most reliable first-line treatment for serious E. cloacae infections, as they have the lowest risk of treatment failure and resistance development 1
- Imipenem is particularly effective, as it has been shown not to select for resistance in E. cloacae strains 2
- For mild to moderate infections, fluoroquinolones like levofloxacin or ciprofloxacin may be used if susceptibility is confirmed 1, 3, 4
Antibiotics to Avoid
- Third-generation cephalosporins (like ceftazidime, ceftriaxone) should be avoided due to high risk of treatment failure and rapid development of resistance through AmpC beta-lactamase induction 5, 1, 2
- First and second-generation cephalosporins (including cefuroxime) are generally not effective against Enterobacter infections 5
Treatment Based on Infection Site
Urinary Tract Infections
- Levofloxacin is FDA-approved for complicated UTIs due to E. cloacae with a recommended 10-day treatment regimen 3
- Ciprofloxacin is also effective for urinary tract infections caused by E. cloacae 4
Intra-abdominal Infections
- For complicated intra-abdominal infections, carbapenems or fluoroquinolones (ciprofloxacin or levofloxacin) plus metronidazole are recommended 5, 1
Bone and Joint Infections
- A combination of fluoroquinolone and cotrimoxazole has shown 80% cure rates in bone and joint infections caused by E. cloacae 6
Treatment for Resistant Strains
- For carbapenem-resistant E. cloacae, newer agents such as ceftazidime-avibactam, meropenem-vaborbactam, or imipenem-cilastatin-relebactam should be considered 1
- For highly resistant strains, combination therapy may be necessary - polymyxin B plus tigecycline has shown promising results against extensively drug-resistant E. cloacae 7
- Cefepime and levofloxacin combination has been successfully used to treat KPC-2 (Klebsiella pneumoniae carbapenemase) producing E. cloacae 8
Common Pitfalls and Caveats
- E. cloacae can rapidly develop resistance to third-generation cephalosporins during therapy due to AmpC beta-lactamase induction or derepression 1
- Tetracyclines alone are not typically first-line agents for E. cloacae infections but may be used in combination therapy for resistant strains 7
- When using aminoglycosides or polymyxins, regular monitoring of renal function is essential 1