From the Guidelines
Rocephin (ceftriaxone) does not effectively cover Enterococcus faecalis. Ceftriaxone is a third-generation cephalosporin that has poor activity against E. faecalis, making it an inappropriate choice for infections caused by this organism. E. faecalis has intrinsic resistance to cephalosporins due to low-affinity penicillin-binding proteins and other resistance mechanisms.
Key Points to Consider
- For E. faecalis infections, more appropriate antibiotic choices include ampicillin or penicillin (if the strain is susceptible), or vancomycin for penicillin-resistant strains 1.
- In serious infections like endocarditis or bacteremia, combination therapy with an aminoglycoside (such as gentamicin) is often recommended for synergistic killing 1.
- For complicated infections, consultation with an infectious disease specialist is advisable to determine the optimal antibiotic regimen based on susceptibility testing 1.
- When treating suspected or confirmed E. faecalis infections, it's crucial to select antibiotics with known activity against this organism rather than relying on ceftriaxone.
Treatment Recommendations
- The combination of ampicillin plus gentamicin is recommended for 4 to 6 weeks for native valve IE and for a minimum of 6 weeks for infection of prosthetic material 1.
- Vancomycin combined with gentamicin for 6 weeks is recommended for native valve IE and for a minimum of 6 weeks for infection of prosthetic material in patients who are unable to tolerate β-lactam therapy 1.
From the Research
Rocephin Coverage for E. Faecalis
- Rocephin, also known as ceftriaxone, is often used in combination with other antibiotics to treat Enterococcus faecalis infections.
- Studies have shown that ceftriaxone can be effective against E. faecalis when used in combination with ampicillin 2, 3, 4 or penicillin 3, 5.
- The synergy between ceftriaxone and ampicillin or penicillin can vary depending on the specific E. faecalis isolate and its susceptibility to these antibiotics 2, 3, 6, 5.
- Some studies have found that ceftriaxone and ampicillin combinations can exhibit synergistic effects against E. faecalis, particularly for isolates with lower penicillin MICs 2, 3.
- However, other studies have found that the synergy between ceftriaxone and penicillin or ampicillin can be reduced or absent for isolates with higher penicillin MICs or specific penicillin-binding protein (PBP) profiles 6, 5.
Key Findings
- Ceftriaxone and ampicillin combinations can be effective against E. faecalis, but the synergy between these antibiotics can vary depending on the specific isolate and its susceptibility 2, 3, 4.
- Penicillin and ceftriaxone combinations can also exhibit synergistic effects against E. faecalis, particularly for isolates with lower ceftriaxone MICs 3, 5.
- The PBP profile of E. faecalis isolates can impact the synergy between ceftriaxone and other beta-lactam antibiotics 6.
- Further research is needed to fully understand the relationship between ceftriaxone susceptibility and synergy with other antibiotics against E. faecalis 3, 6, 5.