Download Streptococcus

Streptococcus
Streptococcus
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Low G+C
Cocci pairs/chains
FA
Non motile, NSF
Capnophiles
Catalase (-)
Peroxidase
Hemolysins
Lancefield Groups
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18 antigens
Cell wall reactivity
Lancefield Groups
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Membrane Ag
Groups A-H, K-V
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Group A
 Strep. pyogenes
Group B
 Strep. agalactiae
Group C, F, G
 Strep equisimilis
 Strep zooepidemicus
 Strep anguinosus
Group D
 E. faecalis
 Strep bovis
 Strep equines
Group K
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Strep salivarius
Viridans
 Strep mutans
 Strep mitis
 Strep sanguis
Pneumococci
Strep Virulence Factors
GAS: Strep pyogenes
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Location
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Skin, mm
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Resp: pharynx
Pathogenicity
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Adhesins
 Protein F and S (fibronectin)
 Lipoteichoic acid (LTA)
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Immune evasion
 Protein M
 Binds to fibrinogen
 Mimics CT/Muscle
antigens
 Capsule (hyaluronic acid)
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Proteins
 Streptolysins (leukocidins)
 Function
 Lyse formed
elements
 Beta hemolysis
 Types
 S = O2 stable
 O = O2 labile
Strep pyogenes
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Enzymes
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Streptokinase
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DNase B
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depolymerize
Hyaluronidase
Proteases
C5a peptidase
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Break down clots
Decrease chemotaxis
Toxins Exotoxins
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Pyrogenic (A, B, C)
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Superantigens
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Increase immune
cytokines
Promote fever
TSS like syndrome
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Sepsis
M1 and M3 strains
Strep pyogenes infections
Strep pyogenes diseases
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Pharyngitis
Scarlet Fever (rash)
Skin
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Pyoderma
Impetigo
Erysipelas
Cellulitis
Strep TSS
Necrotizing fasciitis
Myositis
Immune Mediated
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Rheumatic fever
Glomerulonephritis
Necrotizing Fasciitis and Meningitis
GBS: Strep agalactiae
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Epidemiology
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GI
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Uritogenital
Pathogenicity
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Capsule
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Enzymes
 Proteases
 Hemolysins
 Beta hemolysis
 Hyaluronidase
Disease
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Puerperal fever
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Vaginitis
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UTI
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Endocarditis
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Osteomyelitis
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Newborn
 Meningitis
 Sepsis
 Pneumonia
CAMP test
Group C Strep
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Strep equi
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Strep equisimilis
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strangles
pharyngitis
Strep anginosus
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abscess
Viridans Streptococcus
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Alpha hemolysis
No Lancefield groups
Diseases
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Dental Caries
Endocarditis
Examples
 Strep mitis
 Strep mutans
 Strep oralis
 Strep sanguis
 Strep salivarius (K)
Biofilms
Strep. pneumoniae
Strep pneumonia capsule
Strep pneumoniae
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Epidemiology
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Mouth
Upper respiratory
Dz = lungs
Pathogenicity
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Capsule
Protein A
Phosphorylcholine
Adhesins
Proteases
 Protects from IgA
pneumolysins
Strep pneumonia diseases
Group D Strep
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Examples
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Location: GI
Tests
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E. faecalis
E. faecium
S. bovis
S. equines
Gamma hemolysis
Salt tolerant
Bile tolerant
Pathogenicity
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Bacterocins
Nosocomial
Enterococcus Sequella
Rapid Strep Test
Vaccination
Questions?