Streptococcus Pyogenes

Streptococcus Pyogenes

1. Characteristic

   • most serious
   • inhibits throat, nasopharynx, occasionally skin
   • catalase -

2. Virulence fc

   • Produce surface antigens
     • C-carbohydrate
     • fimbriae
     • M-protein
     • hyaluronic acid capsule
     • C5a protease hinders com.
     • neutrophile response
   • Extracellular toxins
     • streptolysin
     • pyrogenic
     • superantigen
   • Extracellular enzymes
     • streptokinase
     • hyaluronidase
     • DNase

3. Epidemiology & Pathogenesis

   • human reservior
   • children predominant-cutaneous & throat infec.
   • trans-ctc, droplets, fd, fomites
   • entry-skin / pharynx

4. Diseases

   • skin infec.
     • impetigo
     • erysipelas
   • throat infec.
     • S. pharyngitis
   • systemic infec.
     • scarlet fever
     • septicemia
     • pneumonia
     • S. TSS
   • long term effect
     • rheumatic fever
     • acute glomerulonephritis