From the Guidelines
Linezolid 600 mg IV or PO every 12 hours is the recommended treatment for enterococcal infections, including Enterococcus faecium, due to its strong recommendation and low quality of evidence 1.
Treatment Options
The treatment of Enterococcus faecium infections typically involves a combination of antibiotics due to the organism's intrinsic resistance to many antimicrobials.
- Linezolid (600mg IV/oral twice daily) is a recommended option for enterococcal infections, including VRE 1.
- Daptomycin (8-12mg/kg IV once daily) is also an effective option for VRE infections, particularly for bloodstream infections 1.
- Tigecycline (100 mg IV loading dose then 50 mg IV q12 h) may be considered for intra-abdominal infections due to VRE 1.
- Fosfomycin (3 g PO single dose) and nitrofurantoin (100 mg PO every 6 h) may be options for uncomplicated urinary tract infections due to VRE, although the evidence is limited 1.
- High-dose ampicillin (18-30 g IV daily) or amoxicillin (500 mg PO/IV every 8 h) may be considered for uncomplicated urinary tract infections due to VRE, particularly if the isolate is susceptible to ampicillin 1.
Considerations
- Susceptibility testing is crucial in guiding antibiotic therapy, as E. faecium has developed resistance to multiple antibiotics.
- Combination therapy may be considered in severely ill patients or those who fail treatment with traditional options.
- The duration of treatment typically ranges from 7-14 days for uncomplicated infections to 4-6 weeks for endocarditis or other deep-seated infections.
- Infection disease specialist consultation is suggested in patients with poor treatment response or when longer duration of treatment is considered.
From the FDA Drug Label
Daptomycin has been shown to be active against most isolates of the following microorganisms both in vitro and in clinical infections [see Indications and Usage (1)] Gram-Positive Bacteria Enterococcus faecalis (vancomycin-susceptible isolates only) Staphylococcus aureus (including methicillin-resistant isolates) Streptococcus agalactiae Streptococcus dysgalactiae subsp. equisimilis Streptococcus pyogenes The following in vitro data are available, but their clinical significance is unknown At least 90 percent of the following bacteria exhibit an in vitro minimum inhibitory concentration (MIC) less than or equal to the susceptible breakpoint for daptomycin against isolates of similar genus or organism group. However, the efficacy of daptomycin in treating clinical infections caused by these bacteria has not been established in adequate and well-controlled clinical trials Gram-Positive Bacteria Corynebacterium jeikeium Enterococcus faecalis (vancomycin-resistant isolates) Enterococcus faecium (including vancomycin-resistant isolates) Staphylococcus epidermidis (including methicillin-resistant isolates) Staphylococcus haemolyticus
Daptomycin may be active against Enterococcus faecium, including vancomycin-resistant isolates, based on in vitro data. However, the efficacy of daptomycin in treating clinical infections caused by Enterococcus faecium has not been established in adequate and well-controlled clinical trials 2.
From the Research
Antibiotics for Enterococcus faecium
- The treatment of vancomycin-resistant Enterococcus faecium (VREF) infections is a significant challenge, and new therapies are urgently needed 3.
- Quinupristin/dalfopristin is a streptogramin antibiotic that has been shown to be effective against VREF infections, with minimum inhibitory concentrations ranging from 0.5 microgram/ml to 2 micrograms/ml 3.
- However, the development of resistance to quinupristin/dalfopristin during therapy has been observed, and the clinical efficacy of this antibiotic is complicated by the severity of underlying disease in patients with VREF infections 3.
- Other antibiotics, such as daptomycin, linezolid, and tigecycline, have also been used to treat VREF infections, but the emergence of resistance to these agents is a concern 4.
- Combination antimicrobial therapy may be a useful approach for treating VREF infections, particularly in cases where resistance to multiple antibiotics has developed 4.
- The susceptibility of Enterococcus faecium to various antibiotics, including penicillin, tetracycline, and ciprofloxacin, has been studied, and the results show that E. faecium is often resistant to these agents 5.
- Vancomycin-resistant E. faecium bacteremia is a serious infection that can have a high mortality rate, particularly in patients with underlying disease or immunosuppression 6.
- Linezolid is an oxazolidinone antibiotic that has been used to treat VREF infections, but resistance to this agent has been reported, particularly in patients receiving protracted courses of therapy 7.
Treatment Options
- Quinupristin/dalfopristin 3
- Daptomycin 4
- Linezolid 4, 7
- Tigecycline 4
- Combination antimicrobial therapy 4