Streptococcus

Media and growth requirements for all strep
- Facultative anaerobe
- Requires Enriched media
Group A : S. pyogenes gram stain & colony discription
- Pinpoint
- Grayish white
- Translucent
- Usually beta with a wide zone
Pathogenicity for A
- Causes 90% of strep infections
- rheumatic fever
- scarlet fever
- erysipelas
- sepsis
- impetigo
- glomerulonephritis
Biochemical tests for A
- Postive:
- *PYR
- Negative:
- Catalase
- Susceptible to *bacitracin & Most penicillin
- Resistant to SXT
Group B : S. agalactiae gram stain & colony description.
GPC in chains
- Slightly larger colonies than A.
- Semi-opaque
- Bull's eye
- Diffuse beta hemolysis with narrow zone
- Occasionally nonhemolytic
Pathogenicity for B

Normal flora of femal genital tact.

Most common cause of neonatal septicemia and meningitis
Indentification tests for B
- Positive:
- CAMP
- Sodium hippurate
- Negative:
- Catatlase
Resistant to: SXT & Bacitracin

Author

Kwalke12

219369

Card Set

Streptococcus

Description

Strep

Updated

2013-05-16T22:18:14Z

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