Consultation with the Specialist
Enterococcal Infections
Terry Yamauchi MD
Introduction
The enterococci, normal inhabitants of the human and animal bowel flora, were considered for years to be nonvirulent microorganisms. Over the past decade, however, the role of enterococci in human disease has taken on new importance. Serious diseases, such as bacteremia, which is associated with significant mortality, and endocarditis, are prime examples of human enterococcal infections. More recently, the wide-spread use of antimicrobial agents has led to the emergence of multiresistant microorganisms, previously considered to be nonpathogenic, as significant agents in human diseases.
Morphologically, enterococci are gram-positive cocci that grow in chains and resemble streptococci. Previously, enterococci were placed in the Lancefield Group D streptococci genus; currently, they are in a new bacterial genus classification Enterococcus (Table).
Clinical Diseases
Enterococci may cause serious infections in the hospitalized patient and have been reported as the third leading cause of nosocomial infections in the United States. The recovery of enterococci from the urinary tract, surgical wounds, and the blood documents the importance of these bacteria in hospital-acquired infections.
[See table in the PDF file]
The urinary tract is the most common site infected by enterococci. Surgical instrumentation, intervention, and catheterization are invasive procedures that place the patient at risk for enterococcal infection.
