M5 Streptococci

Question 1

Most significant pathenogenic group of streptococci?

Answer 1

Group A streptococci

Question 2

Type of haemolysis does Streptococcus Pyogenes undertake?

Answer 2

Beta - haemolytic

Question 3

A disease that is caused by S.pyogenes?

Answer 3

Scarlet Fever

Question 4

Number of evolutionary groupings of Streptococcus?

Answer 4

6

Question 5

Name the 6 evolutionary groupings of streptococcus

Answer 5

Mitis, Anginosus, Pyogenic, Bovis, Salivarius, Mutans

Question 6

define haemolysis

Answer 6

lysis of RBCs and release of their contents into the surrounding fluid

Question 7

what are the 3 types of haemolysis?

Answer 7

Alpha, beta and gamma

Question 8

what degree of haemolysis occurs on a blood agar plate and what colour is the plate with alpha haemolysis?

Answer 8

partial haemolysis of blood agar plate, green

Question 9

example of alpha-haemolytic strep?

Answer 9

most oral streptococci

Question 10

what degree of haemolysis occurs on a blood agar plate and what colour is the plate with beta haemolysis?

Answer 10

complete haemolysis of blood agar plate, plate is clear

Question 11

example of beta haemolytic strep?

Answer 11

S.pyogenes and the anginosus group

Question 12

what degree of haemolysis occurs on a blood agar plate and what colour is the plate with gamma haemolysis?

Answer 12

no haemolysis of blood agar plate, no show

Question 13

example of gamma haemolytic strep?

Answer 13

enterococcus faecalis

Question 14

describe Lancefield Grouping

Answer 14

further subdivision of Beta and Gamma haemolysis, based on carbohydrate content in bacterial cell wall

Question 15

what are the LF groupings for beta haemolytic strep?

Answer 15

Group A, B, C, E, F

Question 16

what is the LF grouping for gamma haemolytic strep?

Answer 16

Group D

Question 17

What group is further subdivided according to M protein antigen content?

Answer 17

Group A

Question 18

What does G.A.S stand for ?

Answer 18

Group A Streptococci

Question 19

A dental related infection caused by S.pyogenes?

Answer 19

Acute streptococcal gingivitis

Question 20

virulence factors of s.pyogenes?

Answer 20

superantigenic toxins, haemolysins, capsule, M proteins

Question 21

role of haemolysins?

Answer 21

cause tissue damage and ulceration

Question 22

diseases of the skin caused by s.pyogenes?

Answer 22

impetigo, cellulitus, necrotising fasciitis

Question 23

primary reservoir for s.pyogenes?

Answer 23

oropharynx

Question 24

key virulence factoer for evasion of host defences with s.pyogenes?

Answer 24

M proteins

Question 25

main way to distinguish between viral and bacterial throat infections?

Answer 25

viral = no fever, bacterial = fever

Question 26

autoimmune disease by s.pyogenes?

Answer 26

rheumatic fever

Question 27

throat infections by s.pyogenes?

Answer 27

scarlet fever, strep throat