Streptococci

Question 1

Streptococci are gram ______ ______ appearing as ______ cells, ______, or chains (NOT CLUSTERS)

Answer 1

positive; cocci; single; diplococci

Question 2

Hemolytic pattern (3)

Answer 2

B-hemolysis, a-hemolysis; gamma-hemolysis

Question 3

Lancefield group is characterized by ______ ______ ______

Answer 3

cell wall carbohydrate

Question 4

Group A S. progenies (GAS) is ______ sensitive. ______ hemolytic

Answer 4

Bacitracin; beta

Question 5

Group B S. agalactiae (GBS) is found in the ______ tract, encapsulated –> ______ bacteremia & ______. ______ hemolytic

Answer 5

vaginal; neonatal; meningitis; beta

Question 6

Is there prenatal screening for GBS?: T/F

Answer 6

True

Question 7

S. bovis is diagnostic of ______ cancer leading bacteremia & ______. ______-hemolytic in Group ______

Answer 7

colon; endocarditis; alpha; D

Question 8

Viridans is due to ______ ______ and can lead to ______. ______ or ______ hemolytic.

Answer 8

dental plaque; endocarditis; alpha or gamma.

Question 9

GAS is naturally found in ______ and ______ surfaces. Some individuals are ______ carriers.

Answer 9

skin; mucosal; chronic

Question 10

3 types of host-GAS relationships

Answer 10

1. asymptomatic carriers
2. ‘suppurative’ disease: pyogenic infection
3. ‘nonsuppurative’ disease: ARF, not associated with active infection

Question 11

Syndromes of GAS (5)

Answer 11

furuncles, carbuncles, impetigo, cellulitis, toxigenic syndromes

Question 12

GAS: Scarlet fever is associated with ______, and ______ tongue. Diffuse ______-like rash due to ______ exotoxins.

Answer 12

pharyngitis; strawberry; sandpaper; pyrogenic

Question 13

GAS can lead to ______ ______, myositis, pneumonia, and puerperal fever

Answer 13

necrotizing fasciitis

Question 14

Nonsuppurative complications of GAS include 2 things

Answer 14

1. Acute glomerulonephritis (AGN)

2. Acute rheumatic fever (ARF)

Question 15

GAS: Acute glomerulonephritis is triggered by ______ or ______ throat

Answer 15

impetigo; strep

Question 16

AGN causes ______ complexes to deposit in glomeruli, triggering ______ ______ and inflammatory damage.

Answer 16

Ag-Ab; complement activation

Question 17

GAS: ARF is triggered by ______ ______.

Answer 17

strep throat

Question 18

GAS: ARF causes an ______ reaction leading to ______, valvular damage, ______ ______, and ______.

Answer 18

autoimmune; myocarditis; arthritis; chorea (involuntary movement); rash

Question 19

GAS virulence factors include ______ proteins, ______ enzymes, pore-forming toxins, and superantigens. However, it has a specific surface protein called ______ protein.

Answer 19

adhesive; hydrolytic; Protein M

Question 20

Protein M has cell ______, anti-______, and anti-______ properties. Used for ______ ______.

Answer 20

adhesive; phagocytic; complement; strain typing.

Question 21

GAS is gram ______ ______, in chains

Answer 21

positive; cocci

Question 22

GAS is sensitive to ______ and treatments prevents ARF

Answer 22

penicillin

Question 23

GAS: For aggressive necrotizing fasciitis, resection of ______ tissue and treated with ______/______

Answer 23

necrotizing; clindamycin/penicillin

Question 24

GAS has a vaccine: T/F

Answer 24

False

Question 25

S. pneumoniae is spread person-to-person via ______, muscus exchange, and ______% are asymptomatic carriage in nares/throat

Answer 25

aerosol; 15-25%

Question 26

S. pneumoniae spreads via 4 tissues/organs.

Answer 26

1. middle ear/sinus –> otitis media/sinusitis
2. Lungs –> pneumonia
3. blood –> bacteremia/septicemia
4. Meninges –> meningitis

Question 27

S. pneumoniae causes damage via ______, a pore-forming toxin. Leads to ______ ______ and ______

Answer 27

pneumolysin; cell death; inflammation

Question 28

S. pneumoniae has a ______ ______ that is key to invasiveness. There are over ______ serotypes and are anti-______.

Answer 28

polysaccharide capsule; 90; phagocytic

Question 29

Populations that can’t protect against s. pneumoniae capsules include: (6)

Answer 29

1. hypogammaglobulinemia (no differentiating B cells)
2. Complement deficiency
3. asplenia
4. neutropenia
5. Very young children (6-36 months w/o T-antibodies)
6. Elderly > 65 yo

Question 30

S. pneumoniae is gram ______, ______. ______-hemolytic. Treated with a 3rd generation ______ due to emergence of penicillin-resistance.

Answer 30

positive; diplococci; alpha; cephalosporin

Question 31

S. pneumoniae has a vaccine: T/F

Answer 31

TRUE!

Question 32

S. pneumoniae has 2 types of vaccines

Answer 32

1. PPSV23: capsular (splenic, pre-existing lung conditions, elderly)
2. PCV13: conjugated (children <5 yo and elderly)

Question 33

Do S. pneumoniae or S. viridians fall into a Lancefield group?

Answer 33

No!

Question 34

Which Lancefield groups are the most important for human pathogens? (3)

Answer 34

Group A, B, and D.