Enterococcus species
From IDWiki
Enterococcus
Background
Microbiology
- Genus of facultative anaerobic, non-spore-forming, alpha- or gamma-hemolytic, catalase negative, Gram-positive cocci
- Grows on bile esculin agar
- PYR positive
- Most are Lancefield group D
- Commensal gut flora
- Increasing antibiotic resistance
Species
- E. faecalis
- More common (90-95%)
- More commonly genitourinary source
- More susceptible to antibiotics
- E. faecium
- Less common (5-10%)
- More commonly gastrointestinal source
- Less susceptible to antibiotics
- Most common VRE
- E. gallinarum
- E. casseliflavus
- E. hirae, a rare zoonotic pathogen from chickens that can cause bacteremia and endocarditis
Vancomycin Resistance
- Vancomycin binds to d-Ala-d-Ala pentapeptids, interfering with cell wall synthesis
- VanA: most common. Mutation to d-Ala-d-Lac, leading to high resistance to glycopeptides.
- VanB: more common in E. faecium in Australia
- VanC: chromosomal resistance on E. gallinarum and E. casseliflavus
Management
VRE
- Daptomycin, doxycycline, linezolid, tedizolid, oritavancin, quinupristin-dalfopristin (for E. faecium)
References
- ^ Carl-Johan Fraenkel, Måns Ullberg, Sverker Bernander, Evalena Ericson, Peter Larsson, Johan Rydberg, Eva Törnqvist, Åsa Melhus. In vitro activities of three carbapenems against recent bacterial isolates from severely ill patients at Swedish hospitals. Scandinavian Journal of Infectious Diseases. 2006;38(10):853-859. doi:10.1080/00365540600684371.
- ^ James H. Jorgensen, Sharon A. Crawford, Cynthia C. Kelly, Jan E. Patterson. In VitroActivity of Daptomycin against Vancomycin-Resistant Enterococci ofVarious Van Types and Comparison of Susceptibility TestingMethods. Antimicrobial Agents and Chemotherapy. 2003;47(12):3760-3763. doi:10.1128/aac.47.12.3760-3763.2003.
