M5 - Streptococci Flashcards
Is streptococci gram +ve or -ve?
Gram +ve
What type of anaerobe is Streptococci?
Facultative
What is haemolysis?
Break down of RBCs that occurs in infection from strep
How can haemolysis be seen?
Blood agar plates
What type of haemolysis is : partial and produces green colour zones surrounding the bacterial colony?
Alpha
What type of haemolysis is the complete breakdown of RBCs and produces a clear zone surrounding the bacterial colony ?
Beta
What type of haemolysis has no damage to RBCs?
Gamma
What bacteria are known as GAS?
Strep Pyogenes
Are strep pyogenes bacteria gram +ve or -ve?
+ve
Are strep pyogenes alpha haemolytic or beta haemolytic?
Beta haemolytic
What are strep pyogenes sensitive to?
bacitracin
What protein is associated with strep pyogenes?
M protein
What throat infections do strep pyogenes cause?
strep throat
scarlet fever
rheumatic fever
What is scarlet fever?
severe form of strep throat
What is rheumatic fever?
autoimmune disease due to inadequate recovery from GAS
What skin infections are caused by strep pyogenes?
impetigo
cellulitis
necrotising fasciitis
What oral infection normally follows a sore throat?
acute streptococcal gingivits
What are defence systems of the respiratory tract?
- Mechanical washing
- Coughing
- Mucocilliary clearance
- Microbiota/ flora
What are important for colonising the throat ?
surface proteins
What type of protein can certain species of strep produce?
M proteins
What does M protein bind and form a complex with?
fibrinogen
