Strep and similar organisms (Exam 3) Flashcards
What are the beta strep groups?
Group A, B, C, F, and G
What is Lancefeild grouping based on?
The presence of polysaccharide and teichoic acid antigens in the bacterial cell wall
Which organism from this group is responsible for up tp 50% of bacterial endocarditis?
Viridans group
Which organism in this group can be identified by its unique gram stain?
Aerococcus/ GPC clusters
What test is used to differentiate species of Aerococcus?
LAP test
What test is used to confirm the identity of NVS species?
Staph streak test
Which organism of this group may have a pseudo catalase reaction?
Enterococcus
Which organism is susceptible to Bacitracin?
Strep A (pyogenes)
Which organisms is susceptible to Optichin?
Strep pneumoniae
Which organisms belong to the Strep anginosis group?
S. constellatus, S. intermedius, and S. anginosus
Organisms ID: small, grey alpha, GPC in clusters and tetrads; What tests confirm the ID?
Aerococcus; PYR +, BE =, NaCl +
Organism ID: no growth on BAP, grey/grey alphaish, tiny on CHOC; What test will confirm ID?
NVS; Staph streak
Organism ID: Beta hemolytic, heaped white, round colonies, GPB, has a bacterial Strep doppleganger that is very dangerous for pregnant women and the fetus. What is the suspected organisms, how do we differentiate these organisms?
Listeria monocytogenes; A positive catalase test will differentiate from GBS (S. agalactiae)
Which organisms is responsible for causing 50% of bacterial endocarditis?
Viridans Strep group
Which of these organisms can be ID’d by a positive PYR test or a result of BE + /NaCl + ?
Enterococcus
