Necrotizing fasciitis and Streptococcal toxic shock syndrome

Nec. fasciitis caused in 10% by Group A Streptococcus (strep pyogenes) alone

Co-pathogenes are Staph aureus, gram negative enteric rods, bacteroides, rarely marine vibrio

Group A Strep produce exotoxin, some of them activate T-Cells directly to sevrete proinflammatory cytokines (IL1, IL6, TNFa)

Clinical Presentation

  • Rapid onset of pain in the overlying tissue
  • Fever Rigors
  • Toxic shock
  • Skin initially erythematous, then dusky, mottled and oedematous
  • Often bacteraemia (in contrast to Staphylococcal Toxic Shock Syndrome)

Confirmation of diagnosis

  • Clinical suspicion
  • History of penetrating injury (bites, scratches, surgery)
  • Clinical examination
  • Full thickness biopsy
  • Radiology (xray, CT, MRI may show subcutaneous gas)
  • Surgical exploration
  • Microbiological confirmation


  • Resuscitation from shock
  • History, Examination and Investigations
  • Surgical Exploration
  • debridement
  • amputation
  • Antibiotics to cover gram positive, gram negative and anaerobic organisms
    • Betalactams with betalactamase inhibitor
    • Clindamycin (inhibits toxin formation by strep A species)
  • Control of Transmission