Exam 3 Enterococcus sp. Viridians strep and other strep like sp Flashcards
Where do enterococcus colonize
the GI tract
What makes Group D and Enterococcus similar
enterococcus is originally classified as Group D strep because they share the Group D cell wall antigen
What are the common species isolated of enterococcus
E. Faecalis, E, Faecium, E. gallinarum, and E. casseliflavus
What type of hemolysis does Enterococcus species have
alpha, gamma, and beta hemolysis
Is Enterococcus catalase negative or positive
catalase negative (there is weak bubbling in catalase test that causes a pseudeocatalse reaction)
Is enterococcus PYR + or -
PYR +
Is enterococcus BE + or -
BE +
Is enterococcus ‘P’ disk + or -
‘P’ disk -
Is enterococcus 6.5% NaCl + or -
6.5% NaCl +
What are the virulence factors of enterococcus
ability to Adhere to host surfaces
form Biofilms
* Antibiotic Resistance
What are the infections caused by enterococcus
Nosocomial Infections
UTI - enterococcus mainly seen in urinary tract infections from catheterizations
Peritonitis (inflammation in the lining of the membrane that surrounds your abdomen)
How can enterococcus be treated
resistant to penicillin
* Should check for resistance to aminoglycosides
Synergistic therapy: requires combination of
* Cell wall-active agent (such as ampicillin or vancomycin)
* Aminoglycoside (such as gentamicin or streptomycin)
What are VRE
(Vancomycin Resistant Enterococcus)
What makes enterococcus penicillin resistant
Beta-Lactamase – the enzyme produced by bacteria causing resistance to Penicillin
Bacteria can be checked for penicillin resistance with
B-Lactam Disc – quick bench tests
Nitrocefin Disc – quick bench tests
Oxacillin disc – screen for sensitivity or resistance
overnight growth >20mm = sensitive to penicillin
Where do Viridans Strep occur
RT (upper respiratory tract)
Female genital tract
GIT (gastrointestinal tract)
What infections do Viridans strep cause
Bacterial Endocarditis -Viridans streptococci is the etiologic agent in the majority of cases of in the United States
What type of hemolysis does Viridans strep have
Alpha (or gamma) Hemolysis on BAP
Is Viridans strep ‘P’ disk + or -
‘P’ disk -
Is Viridans strep bile esculin + or -
BE -
What is Abiotrophia
Nutritionally variant streptococci
(NVS)
Abiotrophia becomes an opportunistic pathogen in
GI tract and GU tract
Is Abiotrophia hard to treat with antibiotics
yes
Can Abiotrophia grow in a culture
it is hard to grow in culture but it may satellite growth around staph aureus
What is an example of another streptococcus like organisms
Aerococcus (Opportunistic pathogen)
What is MALDI-TOF MS -commercial ID systems
Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry
What are Lancefield classification groups and what are they used for
Classified several different antigens (Carbohydrate groups)
- Group A-D, F, G streptococcus
- Group A = Strep pyogenes
- Group B = Strep agalactiae
- Group D
