Unit 1- Enterococcus Flashcards
Enterococcus
gram positive chains, catalase negative, lancefield group D, facultative anaerobe, non capsulate, non motile
Culture Media
Blood agar, Bile Esculin Azide, MacConkey, high salt, Kenner-fecal
Bile Esculin Azide Agar
Produce dark colonies on media with high bile
MacConkey Agar
Ferments lactose and produces small dark red colonies
Kenner-fecal Agar
Selective media for enterococcus
Hardy Evironments
Hypotonic, hypertonic, acidic, and alkaline resistant and withstands detergents, oxidation, dessication, and heavy metals
Habitat
Normal commensal in colon and bile tract, oral cavity, urethra, and vagina
Body Structures
Collagen binding proteins, endocarditis specific pili, surface proteins, enderococcal polysaccharide on surface, aggregation
Conjugation
Binds bacteria to bacteria to horizontally transfer genes and acquire broad-spectrum antimicrobial resistance
Enzymes
Gelatinase and hyaluronidase
Toxins
Cytolysin, hemolysin, and sex pheromone
Cytolysin
Pore forming on blood cells, kills gram negative competitors
Sex Pheromone
Stimulates expression of aggregation substances to result in conjugation
E. cecorum
Causes osteomyelitis, femoral head necrosis, spondylitis, and arthritis in broiler chickens
Spondylitis
Back and neck pain due to joint inflammation
E. faecalis
Most common pathogen, causes septicemia, mastitis, endocarditis, UTI, and chronic liver disease
Zoonosis
Top cause of nosocomial infection, mostly caused by E. faecalis
Entry Routes
Ingestion
Exit Routes
Spread in feces or urine and milkk
Use as an indicatior
Fecal contamination
Multi Drug Resistance
Naturally resistant, easily pass plasmids to each other
E. faecium
More antibiotic resistant than faecalis but less common cause of infection
Control and Prevention
Effective waste treatment of feces, water sanitation, proper cleaning and disinfection, protect immune system
