Micro: Rheumatic fever Flashcards
1
Q
general characteristics of streptococcus
A
- gram positive cocci in pairs or chains
- catalase negative
- facultative anaerobes
- capnophilic
2
Q
lab identification of S. pyogenes
A
- beta hemolytic on blood agar
- bacitracin sensitive
- PYR positive
- anti-streptolysin O and anti-DNase B titers can be used in identification
3
Q
virulence factor responsible for sandpaper rash and strawberry tongue in S. pyogenes infection
A
- pyrogenic exotoxin
4
Q
positive ASO titer
A
- recent strep pyogenes infection
5
Q
virulence factor responsible for rheumatic fever
A
- M protein
- cross reaction with bodies own antigens (molecular mimicry)
6
Q
role of M protein
A
- binds fibrinogen, IgG, and complement H factor
7
Q
proteins that M protein shares antigens with
A
- cardiac myosin
- sarcolemmal membrane protein
- synovium
- articular cartilage
8
Q
Jones criteria
A
- evidence of recent GABHS plus 2 major manifestations
OR - one major and two minor manifestations
9
Q
major manifestations
A
- J - joints
- O - heart
- N - subcutaneous nodules
- E - erythema marginatum
- S - Sydenham chorea
10
Q
minor criteria
A
- arthralgia, fever
- elevated acute phase reactants
- prolonged PR interval
11
Q
PANDAS hypothesis
A
- genetically susceptible or vulnerable children
- antistreptococcal antibodies cross react with proteins in basal ganglia of brain
- triggers inflammatory response
- results in Sydenhams chorea
