From the Guidelines
Ceftriaxone should not be used as monotherapy for treating Enterococcus infections, as it is not effective against these bacteria due to intrinsic resistance to cephalosporins, including ceftriaxone, as stated in the 2015 ESC guidelines for the management of infective endocarditis 1.
Treatment Options
For Enterococcus infections, appropriate treatment typically includes:
- Ampicillin (200 mg/kg/day i.v. in 4 –6 doses) for susceptible strains, as recommended in the 2015 ESC guidelines for the management of infective endocarditis 1
- Vancomycin (30 mg/kg/day i.v. in 2 doses) for ampicillin-resistant strains, as recommended in the 2015 ESC guidelines for the management of infective endocarditis 1
Combination Therapy
Serious infections like endocarditis or bacteremia require combination therapy with an aminoglycoside (gentamicin 3 mg/kg/day i.v. or i.m. in 1 dose) to achieve synergistic bactericidal activity, as recommended in the 2015 ESC guidelines for the management of infective endocarditis 1 and the 2015 American Heart Association scientific statement for healthcare professionals 1.
Empirical Treatment
If treating empirically for infections where both Enterococcus and gram-negative coverage is needed, appropriate options include:
- Piperacillin-tazobactam
- Ampicillin-sulbactam
- A carbapenem plus vancomycin
Susceptibility Testing
Susceptibility testing is essential for guiding definitive therapy as resistance patterns vary among Enterococcus species, with E. faecium typically being more resistant than E. faecalis, as noted in the 2015 American Heart Association scientific statement for healthcare professionals 1.
Ceftriaxone and Enterococcus
Ceftriaxone is not active against E. faecium, as stated in the 2015 ESC guidelines for the management of infective endocarditis 1, and should not be used as monotherapy for treating Enterococcus infections. However, the combination of ampicillin plus ceftriaxone was reported to be effective for aminoglycoside nonsusceptible Enterococcus faecalis strains, as noted in the 2015 American Heart Association scientific statement for healthcare professionals 1.
From the Research
Enterococcus and Ceftriaxone
- Enterococci are a common cause of hospital-associated infections, and the use of ceftriaxone has been studied in the treatment of Enterococcus faecalis bloodstream infections and infective endocarditis 2.
- Ceftriaxone, in combination with ampicillin, has emerged as a preferred treatment option for these infections, although mortality rates remain high 2.
- However, the use of ceftriaxone has been associated with the promotion of colonization with vancomycin-resistant enterococci due to high biliary concentrations 2.
- The treatment of vancomycin-resistant enterococcal infections is complex and often requires the use of combination antimicrobial therapy, including agents such as daptomycin, linezolid, and quinupristin-dalfopristin 3, 4, 5.
- For the treatment of Enterococcus faecalis infections, ampicillin plus ceftriaxone is a preferred option, but more research is needed to improve patient outcomes 2.
- In the case of vancomycin-resistant enterococcal urinary tract infections, ampicillin, nitrofurantoin, fosfomycin, and doxycycline are possible treatment options, while linezolid and daptomycin should be reserved for confirmed or suspected upper and/or bacteremic infections 6.