L16_Cocci Flashcards Preview

Microbiology > L16_Cocci > Flashcards

Flashcards in L16_Cocci Deck (55)
Loading flashcards...
1

What is the diameter of cocci?

1um

2

Are cocci spore forming?

No

3

What are the only reservoir for cocci?

Humans

4

Can cocci be cultured easily?

Yes

5

What are the 5 relevant streptococci species?

Group A (sore throats), Group B (meningitis), Pneumococci (pneumonia), Viridans Streptococci (Endocarditis), Enterococci (Abscesses)

6

What are the 3 relevant Staphylococci species?

S. Aureus (abscesses), S. Epidermidis (Catheters), S. saprophyticus (UTI)

7

What are the 2 relevant Neisseria species?

N. meningitides, N. gonorrhoeae

8

What does the catalase test test for?

Ability to break down H2O2

9

How can you identify streptococci?

Gram Positive, Catalase negative, chains

10

What are the possible results of a hemolysis test, and what do they represent?

Beta= completely breakdown
alpha= partially break down
gamma= do not break down

11

Describe the test results that identify group A strep

Gram positive, catalase negative, beta hemolytic, bacitracin sensitive

12

Describe the test results that identify group B strep

Gram positive, catalase negative, beta hemolytic, bacitracin resistant

13

What are the virulence factors of Group A strep (structural and toxins)

Structural: Pili and M protein
Toxins: streptokinase (breaks blood clots), streptodornase, hyaluronidase (breaks down tissue), pyrogenic toxin, erythrogenic toxin

14

What kind of infections do group A strep cause?

Surface infections (sore throats), they spread, they cause fever

15

What is the reservoir and transmission for group A strep

carriers or infected patients, and direct contact. (Dogs can carry too)

16

What are 3 possible sequelae that can be observed a couple weeks after a group A strep infection?

streptococcal nephritis (After Strep B)
Rheumatic Fever (after Strep A)
Sydenham's chorea (OCD)
Non show signs of the bacteria, this is after they are cleared

17

Are there rapid office tests for Group A strep?

Yes but they a less sensitive.

18

What species is Group A strep?

S. pyogenes

19

How can you type Group B strep in the lab?

Gram positive, catalase negative, beta hemolytic, bacitracin resistant

20

What species is Group B strep?

S. agalactiae

21

What is the CAMP test? and what does it comfirm

The hemolytic toxins of S. aureus and group B strep are synergistic. This test shows that where the toxins meet that hemolysis increases and confirms that you strep is group B

22

What is the virulence factor of Group B strep?

Capsule

23

What is the reservoir and transmission of group B strep

Reservoir is genital tract and transmission is neonatal- to baby

24

What antibiotic are Group B always sensitive to?

Penicillin

25

Is there a vaccine for strep group A or B?

No

26

How would you identify Streptococci pneumoniae in the lab?

Gram positive, catalase negative, alpha hemolytic, bile/optochin sensitive

27

What clumping pattern do S. Pneumoniae show?

dipplococci

28

What is the virulence factor of S. pneumoniae?

Capsule

29

How can capsule of S. pneumoniae be used in the lab?

serotyping and vaccine (not great vaccine)

30

What is the reservoir for S. pneumoniae

Humans