M5 - Streptococci

Question 1

Is streptococci gram +ve or -ve?

Answer 1

Gram +ve

Question 2

What type of anaerobe is Streptococci?

Answer 2

Facultative

Question 3

What is haemolysis?

Answer 3

Break down of RBCs that occurs in infection from strep

Question 4

How can haemolysis be seen?

Answer 4

Blood agar plates

Question 5

What type of haemolysis is : partial and produces green colour zones surrounding the bacterial colony?

Answer 5

Alpha

Question 6

What type of haemolysis is the complete breakdown of RBCs and produces a clear zone surrounding the bacterial colony ?

Answer 6

Beta

Question 7

What type of haemolysis has no damage to RBCs?

Answer 7

Gamma

Question 8

What bacteria are known as GAS?

Answer 8

Strep Pyogenes

Question 9

Are strep pyogenes bacteria gram +ve or -ve?

Answer 9

+ve

Question 10

Are strep pyogenes alpha haemolytic or beta haemolytic?

Answer 10

Beta haemolytic

Question 11

What are strep pyogenes sensitive to?

Answer 11

bacitracin

Question 12

What protein is associated with strep pyogenes?

Answer 12

M protein

Question 13

What throat infections do strep pyogenes cause?

Answer 13

strep throat
scarlet fever
rheumatic fever

Question 14

What is scarlet fever?

Answer 14

severe form of strep throat

Question 15

What is rheumatic fever?

Answer 15

autoimmune disease due to inadequate recovery from GAS

Question 16

What skin infections are caused by strep pyogenes?

Answer 16

impetigo
cellulitis
necrotising fasciitis

Question 17

What oral infection normally follows a sore throat?

Answer 17

acute streptococcal gingivits

Question 18

What are defence systems of the respiratory tract?

Answer 18

• Mechanical washing
• Coughing
• Mucocilliary clearance
• Microbiota/ flora

Question 19

What are important for colonising the throat ?

Answer 19

surface proteins

Question 20

What type of protein can certain species of strep produce?

Answer 20

M proteins

Question 21

What does M protein bind and form a complex with?

Answer 21

fibrinogen