- Normal flora of the intestinal
tract in humans and animals.
- Usually the patient's own fecal
flora; some transmission is patient-to-patient.
- Responsible for about 10% of all
nosocomial infections (def).
- Most common infections are urinary
tract infections (UTIs) and bacteremia (def).
- Other infections include endocarditis
as a complication of bacteremia and wound infections; infections within the
peritoneal cavity including intra-abdominal abcesses (usually polymicrobial
especially following penetrating trauma such as gunshot wounds, knife
wounds, and surgical wounds; kidney infections as a complication of UTIs,
prostate infections, and infections of damaged or compromised skin, such as
diabetic or decubitus ulcers, burns, and surgical wounds (often polymicrobial
- The enterococci have become the
second most common bacterium isolated from nosocomial urinary and wound infections,
and the third most common cause of nosocomial bacteremia. Each year in the
U.S., in fact, enterococci account for approximately 110,000 urinary tract
infections, 40,000 wound infections, 25,000 cases of nosocomial bacteremia,
and 1100 cases of endocarditis.
- Predisposing factors include:
- urinary (def)
and intravascular (def)
- long-term hospitalization
while receiving broad-spectrum antibiotics.
- Fimbriae-like proteins originating
in the cytoplasmic membrane that promote attachment to epithelial cells as
well as plasmid (def)
- Various cell wall adhesins (def)
that promote attachment to cells of the intestinal tract.
- Secreted cytolysin that inhibits
growth of other intestinal gram-positive bacteria to facilitate enterococcal
colonization; also induces local tissue damage.
- Secreted pheromone that is a chemoattractant
for neutrophils and subsequently promote inflammatory reactions.
- Secreted gelatinase that hydrolizes
collagen and hemoglobin.
- Inherently resistant to many beta-lactam
antibiotics; acquires resistance genes to aminoglycosides and vancomycin (VRE
or vancomycin-resistant enterococci.) See antibiotic
table. The enterococci are among the most antibiotic resistant of all
bacteria, with some isolates resistant to all known antibiotics.
- aminoglycosides plus vancomycin;
linezolid; streptogramin; selected fluoroquinolones* (see
*Drugs may change with time.
For a more detailed article on Enterococcus
infection in females, see Enterococcal
Infections, by Curtis J Donskey, MD, Chairman of Infection Control, Instructor,
Department of Internal Medicine, Section of Infectious Diseases, Stokes Cleveland
VA Medical Center, Case Western Reserve University and Robert
A Salata, MD, Chief and Clinical Program Director of Division of Infectious
Diseases, Vice Chair for International Affairs, Professor, Department of Medicine,
Case Western Reserve University School of Medicine
Kaiser's Microbiology Home Page
Copyright © Gary E. Kaiser
All Rights Reserved
Updated: January 4, 2005
Please send comments and inquiries to Dr.