Enterococcus is a genus of lactic acid bacteria of the phylum Firmicutes. Members of this genus were classified as Group D Streptococcus until 1984 when genomic DNA analysis indicated that a separate genus classification was appropriate.
Enterococci are Gram-positive cocci which often occur in pairs (diplococci) and are difficult to distinguish from Streptococci on physical characteristics alone. Two species are common commensal organisms in the intestines of humans: E. faecalis (90-95%) and E. faecium (5-10%). Enterococci are facultative anaerobic organisms, i.e. they prefer the use of oxygen, but they can survive in the absence of oxygen. They typically exhibit gamma-hemolysis on sheep's blood agar.
From a medical standpoint, the most important feature of this genus is their high level of endemic antibiotic resistance. Some Enterococci are intrinsic resistant to β-lactam-based antibiotics (some penicillins and virtually all cephalosporins) as well as many aminoglycosides. In the last two decades, particularly virulent strains of Enterococcus which are resistant to vancomycin (Vancomycin-resistant enterococcus, or VRE) have emerged in nosocomial infections of hospitalized patients especially in the US. Other developed countries such as the UK have been spared this epidemic, and in 2005, Singapore managed to halt an epidemic of VRE. VRE may be treated with Quinupristin/dalfopristin (Synercid) with response rates of approximately 70%.
Enterococcal meningitis is a rare complication of neurosurgery. It often requires treatment with intravenous vancomycin; intrathecal vancomycin is often used and it is debatable whether this has any impact on outcome. The removal of any neurological devices is a crucial part of the management of these infections.
Enterococci species in Gulf Coast marine water samples as measured by the Environmental Protection Agency Method 1600.
May 01, 2006; Abstract. -- Enterococcus density, as determined by the United States Environmental Protection Agency Method 1600, is used...