Streptococcus pneumoniae Flashcards
1
Q
What infection is pneumococci associated with?
A
HIV
2
Q
Is pneumococci alpha, beta or gamma haemolytic?
A
Alpha haemolytic
3
Q
What is the key virulence factor of pneumococci?
A
Polysaccharide capsule
4
Q
What infections are caused by S. pneumoniae?
A
- Meningitis
- Occult bacteremia
- Otitis media
- Sepsis with haemorrhagic shock
- Pneumonia
- Arthritis
- Peritonitis
5
Q
Other than humans, what can S. pneumoniae infect?
A
Horses
6
Q
What is the first step in infection with S. pneumoniae?
A
Colonisation
7
Q
Where does S. pneumoniae colonise?
A
Upper respiratory tract
8
Q
What are the risk factors for S. pneumoniae infection?
A
- No spleen
- Viral infection
- Heart disease
- Age
- Diabetes
- Alcoholism
- HIV infection
- Smoking
9
Q
What shape is Streptococcus pneumoniae?
A
Diplococci
10
Q
Is S. pneumoniae gram positive or gram negative?
A
Gram positive
11
Q
How is S. pneumoniae identified?
A
- Alpha haemolytic on blood agar
- Very mucoid
- Production of large amounts of hydrogen peroxide causes greening around the colonies
- Sensitivity to optochin
- Solubility in bile
- Catalase negative
- Quellung reaction
