Enterococcal Infections

Key Features

• Two species—Enterococcus faecalis and Enterococcus faecium— are responsible for most human enterococcal infections

Clinical Findings

• Wound infections

• Urinary tract infection

• Bacteremia

• Endocarditis

• Meningitis

Diagnosis

• Cultures of blood, affected fluids, or tissue

Treatment

• Most enterococcal infections can be treated with

  • Penicillin, 3 million units every 4 hours intravenously

  • Ampicillin (which is slightly more active than penicillin in vitro), 2 g every 6 hours intravenously

  • Vancomycin, 1 g every 12 hours intravenously

• Add gentamicin, 1 mg/kg every 8 hours intravenously for a duration of 2–3 weeks, to above regimens to achieve bactericidal activity required to cure

  • Endocarditis

  • Meningitis

• Quinupristin/dalfopristin and linezolid are FDA approved for treatment of infections caused by vancomycin-resistant strains of enterococci (VRE)

• Daptomycin, tigecycline, tedizolid, and oritavancin are not FDA approved for the treatment for VRE, although they are frequently active in vitro

• Quinupristin/dalfopristin

  • Not active against strains of E faecalis

  • Should be used only for infections caused by E faecium

  • Dose is 7.5 mg/kg every 8–12 hours intravenously

• Linezolid

  • An oxazolidinone

  • Active against both E faecalis and E faecium

  • Dose is 600 mg twice daily (both intravenous and oral formulations are available)