Streptococcus pyogenes

Question 1

what is the bacteria?

Answer 1

Streptococci

Question 2

Streptococci

• gram?
• shape?
• initially classified by?

Answer 2

• gram POSITIVE
• coccus
• pattern of hemolysis on blood agar

Question 3

3 types of hemolytic

Answer 3

• alpha
• beta
• gamma

Question 4

Alpha-hemolytic

• bacteria?
• 3 viridians groups?

Answer 4

• S. pneumoniae
• S. virdins
• S. mutans
• S. thermophilus

Question 5

Beta-hemolytic

• Group A Strep?
• Group B Strep?

Answer 5

• S. pyogenes

- S. agalactiae

Question 6

Gamma-hemolytic

• Group D Strep?
• Group N Strep?

Answer 6

• Enterococcus species

- Lactococcus lactis

Question 7

S. pyogenes

• intra/extracellular?
• __ specific?

Answer 7

• extracellular

- human

Question 8

S. pyogenes

• major cause of mortality? (3)
• common cause of? (2)

Answer 8

• scarlet fever, puerperal sepsis, wound infections

- pharyngitis, impetigo

Question 9

S. pyogenes

• causes?
• cause of ‘post infection sequelae’?

Answer 9

• invasive streptococcal disease
• streptococcal toxic shock syndrome
• acute rheumatic fever

Question 10

M Protein

• anti-___ cell __ expressed protein
• binds ___
• protects strep from ____

Answer 10

• phagocytic, surface
• C4-binding protein
• complement system

Question 11

M Protein

• ___ to particular M protein ___
• ___ and kill bacteria

Answer 11

• antibodies, serotypes

- opsonize

Question 12

Hyaluronic acid capsule

• what is it?
• major component of ___ –> __ make vaccine
• block ___ through __

Answer 12

• polysaccharide
• host tissues, can NOT
• opsonization, C3b

Question 13

Hemolysins

• name?
• 2 types

Answer 13

• streptolysins

- S and O

Question 14

S streptolysin

- function?

Answer 14

• beta hemolysis

Question 15

O streptolysin

- function?

Answer 15

O2 sensitive

Question 16

Superantigens

• secreted ___
• type?
• activators of ___
• causes?

Answer 16

• exotoxins
• streptococcal pyrogenic
• T Cells
• cytokine storm

Question 17

Pharyngitis

• severe __
• no __
• swollen ___
• tonsillar __

Answer 17

• sore throat
• COUGH
• cervical lymph nodes
• exudate = pus

Question 18

Pharyngitis - Diagnosis

• what test?
• positive
• negative

Answer 18

• rapid strep test
• (+) = strep throat
• (-) = throat culture

Question 19

Pharyngitis - Treatment

• which 2?
• why one over other?
• untreated?

Answer 19

• Beta lactams and erythromycin
• Beta lactams have no resistance!!
• lead to acute rheumatic fever

Question 20

Impetigo

• superficial __ infection
• red ___
• highly ___

Answer 20

• skin
• sores
• contagious

Question 21

Scarlet Fever

• key characteristic?
• __ develop during strep
• ___ mediated

Answer 21

• strawberry tongue
• rash
• toxin

Question 22

Invasive Streptococcal Disease

• isolation of ___ from ___ sterile site
• soft tissue?
• muscle?
• ____

Answer 22

• S. pyogenes, normal
• necrotizing fasciitis
• necrotizing myositis
• streptococcal TSS

Question 23

Invasive Streptococcal Disease Risk Factors

• __ injury
• __ pox
• after childbirth?
• lack of immunity to?

Answer 23

• tissue
• chicken
• postpartum
• superantigens + M Protein

Question 24

Invasive Streptococcal Disease Treatment (3)

Answer 24

• antibiotics
• debridement
• IVIG (neutralize superantigen activity)

Question 25

Mouse Model - superantigens __ bind to mouse MHC class II - deletion of ___ can't infect = ___ infection - ____ blocked infection

Answer 25

- DO NOT - SpeA, drive - anti-SpeA

Question 26

Rheumatic Fever - __ infection - autoimmunity --> __ cross reactivity with __ - 2 forms?

Answer 26

- AFTER - antibody, M-Protein - acute rheumatic fever and rheumatic heart disease