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Bacteria under Microscope
Streptococcus pyogenes
Group A streptococcus
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Gram-stain: |
Gram-positive cocci |
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Microscopic appearance: |
Cocci in clusters, short chains, diplococci and single cocci |
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Clinical significance: |
- It is an infrequent, but usually pathogenic, part of the skin flora.
- S. pyogenes is the cause of many important human diseases, ranging from mild superficial skin infections to life-threatening systemic diseases.
- pharyngitis ("strep throat")
- localized skin infection ("impetigo")
- Erysipelas and cellulitis
- Necrotizing fasciitis
- Scarlet fever
- Streptococcal toxic shock syndrome
- Rheumatic fever
- Acute postinfectious glomerulonephritis
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Text: Wikipedia |
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Colony morphology: |
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A |
B |
C |
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Streptococcus pyogenes identification |
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A |
Beta-hemolytic colonies of Streptococcus pyogenes on sheep blood agar. Cultivation 24 hours, aerobic atmosphere, 37°C. |
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B |
Colonies of Streptococcus pyogenes (Group A streptococcus, abbreviated GABHS) on sheep blood agar. Beta-hemolysis around colonies.
Cultivation 24 hours in an aerobic atmosphere, 37°C. |
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C |
S.pyogenes on Columbia agar with 5% defibrinated sheep blood, 24 hours in an aerobic atmosphere, 37°C.
Colonies are surroundend by a wide zone of beta-hemolysis. |
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www.bacteriainphotos.com |
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