L16_Cocci

Question 1

What is the diameter of cocci?

Answer 1

1um

Question 2

Are cocci spore forming?

Answer 2

No

Question 3

What are the only reservoir for cocci?

Answer 3

Humans

Question 4

Can cocci be cultured easily?

Answer 4

Yes

Question 5

What are the 5 relevant streptococci species?

Answer 5

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

Question 6

What are the 3 relevant Staphylococci species?

Answer 6

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

Question 7

What are the 2 relevant Neisseria species?

Answer 7

N. meningitides, N. gonorrhoeae

Question 8

What does the catalase test test for?

Answer 8

Ability to break down H2O2

Question 9

How can you identify streptococci?

Answer 9

Gram Positive, Catalase negative, chains

Question 10

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

Answer 10

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

Question 11

Describe the test results that identify group A strep

Answer 11

Gram positive, catalase negative, beta hemolytic, bacitracin sensitive

Question 12

Describe the test results that identify group B strep

Answer 12

Gram positive, catalase negative, beta hemolytic, bacitracin resistant

Question 13

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

Answer 13

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

Question 14

What kind of infections do group A strep cause?

Answer 14

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

Question 15

What is the reservoir and transmission for group A strep

Answer 15

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

Question 16

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

Answer 16

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

Question 17

Are there rapid office tests for Group A strep?

Answer 17

Yes but they a less sensitive.

Question 18

What species is Group A strep?

Answer 18

S. pyogenes

Question 19

How can you type Group B strep in the lab?

Answer 19

Gram positive, catalase negative, beta hemolytic, bacitracin resistant

Question 20

What species is Group B strep?

Answer 20

S. agalactiae

Question 21

What is the CAMP test? and what does it comfirm

Answer 21

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

Question 22

What is the virulence factor of Group B strep?

Answer 22

Capsule

Question 23

What is the reservoir and transmission of group B strep

Answer 23

Reservoir is genital tract and transmission is neonatal- to baby

Question 24

What antibiotic are Group B always sensitive to?

Answer 24

Penicillin

Question 25

Is there a vaccine for strep group A or B?

Answer 25

No

Question 26

How would you identify Streptococci pneumoniae in the lab?

Answer 26

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

Question 27

What clumping pattern do S. Pneumoniae show?

Answer 27

dipplococci

Question 28

What is the virulence factor of S. pneumoniae?

Answer 28

Capsule

Question 29

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

Answer 29

serotyping and vaccine (not great vaccine)

Question 30

What is the reservoir for S. pneumoniae

Answer 30

Humans

Question 31

What is the main mechanism of resistance against pneumococci?

Answer 31

mechanical clearance by mucus and cilia sweep it out of the respiratory tract and it gets swallowed and killed in the GI tract

Question 32

Why do alcoholics get bacterial pneumonia frequently?

Answer 32

depressed cough reflex

Question 33

how do you identify Strep Viridans in the lab?

Answer 33

Gram pos, catalase neg, alpha hemolytic, bile/optochin resistant

Question 34

What is the reservoir and virulence factors of Viridans Streptococci?

Answer 34

Mouth of people 100%, sugar metabolizing enzymes (can break down into acids which decalcify, or they can build up into dental plague and release can cause bacteremia and endocarditis) They are Sticky

Question 35

how do you treat S. Viridans?

Answer 35

Penicillin

Question 36

How do you type streptococci faecalis in the lab?

Answer 36

Gram pos, catalase negative, gamma hemolytic, bile/optochin resistant

Question 37

How do you ID staphylococci in the lab?

Answer 37

Gram pos, catalase pos

Question 38

How do you ID S. aureus in the lab?

Answer 38

Gram pos, catalase pos, coagulase pos

Question 39

What are the virulence factors of S. Aureus?

Answer 39

Structural: Protein A, capsule, coagulase Toxins: DNAse, enterotoxin, exfoliatin, toxic shock syndrom, leukocidin

Question 40

Do S. Aureus infections tend to spread?

Answer 40

No they tend to stay where they are and cause abscesses

Question 41

What is a major problem of S. aureus?

Answer 41

They are multi drug resistant

Question 42

How do you ID Staph epidermidis in the lab?

Answer 42

Gram positive, catalase positive, coagulase negative, novobiocin sensitive

Question 43

Where do you find S. epidermidis infections a lot?

Answer 43

infections with piercings, and catheter surfaces

Question 44

How do you ID S. saprophyticus?

Answer 44

gram positive, catalase positive, coagulase negative, novobiocin resistant

Question 45

How do you ID N. meningitidis?

Answer 45

Gram neg, fermentation of maltose on chocolate agar

Question 46

How do you ID N. gonnorhoeae?

Answer 46

Gram Neg, no fermentation of maltose on chocolate agar

Question 47

What is the virulence factors of N. meningitidis?

Answer 47

capsule and LPS

Question 48

What is the virulence factors of N. gonorrhoeae?

Answer 48

pili and LOS

Question 49

Where does meningitidis cause infections? gonorrhoeae?

Answer 49

meningitidis - deeper tissues | Gonorhheae - surfaces

Question 50

What is the reservoir, transmission and prevention of N. Meningitidis?

Answer 50

Reservoir is resp. tract and carriers transmission is droplets Prevention is Vaccine

Question 51

What is the reservoir, transmission and prevention of N. Gonorrhoeae?

Answer 51

Reservoir: genital tract and chronic infection Transmission: sexual contact and birth Prevention: Behavioral and Neonatal eye drops

Question 52

How do you treat N.Meningitidis vs N. Gonorrhoeae?

Answer 52

Menigitidis- penicillin | Gonorrhoeae- Not penicillin (its resistant) Ceftriaxone plus doxycycline

Question 53

What are the two Cocci that can have a vaccine made for them?

Answer 53

S. pneumoniae and N. Meningitidis

Question 54

How does Lancefield typing work?

Answer 54

by identifying carbohydrate antigens

Question 55

What does the capsule of pneumococci cause the immune system to do?

Answer 55

Produce opsonizing antibody