1. Streptococcus Cell Identifiers
    • Gram Positive Cocci
    • Ferment lactic acid
    • Catalase negative
    • Facultative Anaerobes
    • Unable to synthesize heme
  2. alpha hemolysis
    • - incomplete lysis of cells (greenish)
    • S. pnemoniae
    • S. sanguis
  3. beta hemolysis
    • - complete lysis
    • A- S. pyogenes
    • B- S. agalactiae
  4. gamma hemolysis
    • - no lysis
    • Enterococci (used to be grouped with streptococcus)
  5. S. pyogenes
    • Lancefield antigen is cell wall carbohydrate
    • Causes a lot of different diseases
  6. S. pyogenes
    Aerosol Exposure
    • sore throat, pharyngitis (tonsilitis)
    • may cause complications:

    • Rheumatic Fever
    • Endocarditis
    • Arthritis
    • Scarlet Fever (red spots)
  7. Complications with immune system fighting S. pyogenes
    • When body creates antibody to M
    • proteins on S. pyogenes. May also attack host cells.
  8. Other diseases of S. pyogenes
    • Lung exposure- pnemonia
    • Ear- otitis
    • Meninges- meningitis
    • Skin- empatigo
    • Kidney- glomerulonephritis
    • Necrotitis Fisciitis- flesh eating disease
  9. S. pyogenes Virulence Factors
    • Capsule of hyuronic acid (not recognized by body as foreign)
    • Lipotechoic Acid & F Proteins- bind fibronectin
    • M Protein- binds fibrinogen / calligen
    • Pyogenic endotoxins- superantigens
  10. Lab Detection of S. pyogenes
    • PCR
    • Serology
    • Look for beta hemolysis (A)
  11. Treatment of S. pyogenes
    Penicillin or Erythromycin
  12. S. agalactiae
    Beta hemolysis (B)
  13. Disease of S. agalactiae
    • Neonatal disease- pnemonia, meningitis, septicemia
    • Inhabits vagina. Women are checked during pregnancy.
    • Doesn't really cause disease in healthy adults
    • Associated with wound infections in diabetics
  14. Virulence Factors of S. agalactiae
    • Salic acid capsule (displayed in human cells "molecular mimicry"
    • C5a peptidase
    • Cell lysis enzymes
  15. Lab Identification of S. agalactiae
    cAMP test + : Lysis of sheep RBC in combination with S. aureus

    Hippurate Hydrolysis +
  16. Treatment of S. agalactiae
    Penicillin & Aminoglycosides
  17. Alpha Hemolytic & Cavities
    • Don't use Lancefield to identify
    • S. mutans & S. sanguis (plaque on teeth)-> produce lactic acid (cavities)
    • From mouth, can get into heart -> Endocarditis
    • Treat with penicillin
  18. S. pnemoniae
    • Naturally transformable (pick up DNA from environment)
    • Older cultures stain Gram Negative
    • Grow in aerobic= Greenish (alpha)
    • Grow in anaerobic= Cleaning
  19. Diseases of S. pnemoniae
    Arthritis, sepsis, meningitis

    Pneumococcal pnemonia (from X Ray)- lobar
  20. S pnemoniae disease
    • -Blood tinged sputum (spit blood)
    • -Usually a secondary infection to a primary viral infection that weakened lungs
    • -Usually only young and old die
  21. Two Colony Phenotypes of S. pnemoniae
    • 1. Transparent (from nose, throat, lung)
    • 2. Opaque (Grown in lab)
  22. Virulent Factors of S. pnemoniae
    C Polysaccharide on capsule- precipitates C Reactive Protein, a sign of acute inflammation

    IgA Protease

    Pneumolysin- Lyse cilliated cells in upper respiratory tract
  23. Lab Identification of S. pnemoniae
    • Capsule can't be stained
    • Ferments
    • alpha hemolytic
    • Bile Solution Test
    • Qwuelling Test (detect capsule)
    • Optochin Susceptibility (all other Strep are optochin resistant)
  24. Treatment of S. pnemoniae
    • Penicillin (1/3 are resistant)
    • Erythromycin, Chloramphenicol
    • Polyvalent Vaccine
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