Enterococcus faecalis
Enterococcus faecalis
Enterococcus faecalis (including Streptococcus faecalis ) is a naturally occurring gram-positive in the intestine of humans and animals bacterium. The catalase -negative cocci are often arranged in pairs or in chain form. There are undemanding organisms, those which have both anaerobic and aerobic metabolism.
Proof
On blood agar, one can observe an α -, β - or no hemolysis. Enterococcus faecalis is largely resistant to bile salts and optochin. It is heat stable (growth at 45 ° C ) and salt tolerant (growth in 6.5 % NaCl solution). They also hydrolyze esculin. They carry the Lancefield group D antigen, but the extraction of the antigen is more difficult than for the streptococci, enterococci as teichoic acid having more and less polysaccharide.
Clinical Significance
There are known both pathogenic and non-pathogenic strains. So far, neither toxins nor other virulent factors could be detected plasmid- transferred hemolysin may play a role.
The pathogenic strains cause nosocomial infections in people with weakened immune systems. Furthermore, endocarditis, as well as bladder, prostate, and epididymal infections can be triggered. That the infection of the nervous system are rare. Poor hygiene or weakening of the immune system, a vaginitis ( vaginosis ) by Enterococccus faecalis can be induced.
In some strains of the bacterium antibiotic resistance were to chloramphenicol (Cm ), erythromycin ( Emr ), demonstrated tetracycline ( Tc ) and minocycline ( Mnr ). Mainly in hospitals of the bacterial strains were found resistant to ampicillin at 13%. Of 676 strains examined have only 0.1 % on a Amoxicillinresistenz.
Synonyms
In 1984, the species Streptococcus faecalis and Streptococcus faecium to the genus Enterococcus were assigned (new Enterococcus faecalis and Enterococcus faecium ).