Streptococcacease Part II Flashcards
What is the microscopic shape/gram stain of Streptococcus genera?
Gram Pos cocci, Pairs and chains, football or lancet shaped
Describe a staphylococcus plate
Opaque
Describe a streptococcus plate
Transparent, not as opaque
What is group A bacteria? How does it get its name?
Streptococcus pyogenes, pus forming
What is group B bacteria?
Streptococcus agalactoae
What are characteristics of Streptococcus pyogenes?
Group A, M protein, Emm gene sequencing
What are disease with streptococcus pyogenes?
Strep throat, scarlet fever, necrotizing faciitis (flesh eating bacteria)
What is the cause of streptococcal toxic shock syndrome?
Pyrogenic exotoxin
What are two diseases post streptococcal infection?
acute glomerulonephritis and Rheumatic Fever
What is the cause of acute glomerulonephritis
Not infection of the kidney, ag-Ab complexes
What is the cause of Rheumatic Fever?
After pharyngitis, damage to heart valves, not an infection of the heart
Why is M protein virulent?
Resistant to phagocytosis
Why is Pyrogentic toxin virulent?
Rash of scarlet fever
Why is streptokinase/fibrinolysin virulent?
Spreading infections
Why is hyalronidase virulent?
Spreading infections
What are other exotoxins virulent?
Fever, shock, tissue damage
What strep are throat screens run on, what about the others? Why?
Only run on group A as these are the only ones that can lead to other diseases, group B are not treated
What incubator is SBA throat screen placed in. WHY?
anaerobically, due to streptolysin O (oxygen labile)
What is done when a rapid test screen is pos? when it is neg?
Pos is conclusive, neg, you have a culture preformed because it COULD still be positive. The ag detection is only 85% sensitive
What is the treatment for streptococcus group A?
Penicillin
What are the characteristic of streptococcus agalactiae?
Lancefield group B, beta hemolytic, large colonies but smaller zone of hemolysis compared to A
When are group B streptococcus cultures preformed, in what media?
35-37 gestation in LIM broth
What is the most common infection for babies
Group B strep
What is the most common bacterial cause of pneumonia?
streptococcus pneumoniae
What are the gram stain and plate characteristics of streptococcus pneumoniae?
Diplococci, FOOTBALL/LANCET SHAPPED, Alpha hemolytic and autolysis (dipped)
What are the two most common causes of viridans streptococci?
subacute endocarditis and oral infections
How are group D and not group D alpha streptococci differentiated?
Bile esculin
What condition goes along with positive septicemia and streptococcus bovis?
colon cancer
What are the two most common species of enterococcus? which one is more resisitant?
E. Faecalis and E. faecium, faecium is more resistance
What are the causing agents of culture negative endocarditis?
Abiotrophia
What is characteristic of a plate with satellite colonies?
Abiotrophia
What bacteria causes a staph looking gram stain and a strep looking plate?
Aerococcus
What species are lactic acid bacteria?
Leuconostoc and Pediococcus
What are characteristics of Leuconostoc and Pediococcus
Lactic acid from glucose and resistant to Vancomycin
Beta, PYR+, Bacitracin susceptible
Group A
Beta, CAMP+, NaHippurate+, NaCl+
Group B
Usually Alpha or Gamma, Bile Esculin +, NaCl- and PYR-
Group D
ALPHA, Optochin susceptible, bile solubility positive and quelling test positive
Streptococcus pneumoniae
Alpha or Gamma, Bile esculin, NaCl and PYR all +
Enterococcus spp.
Neg for all tests and Alpha
Alpha streptococcus not group D
Neg for all tests and Beta
Beta streptococcus not group A, B or D
Diplococci, FOOTBALL/LANCET SHAPPED, Alpha hemolytic and autolysis (dipped)
streptococcus pneumoniae
