Necrotizing Fasciitis 101

General

  • Skin and soft tissue infection that extends to involve the fascia and muscles
  • Often associated with pre-existing skin infection, trauma, chronic ulcers, surgical wounds

Pathegenesis and Risk

  • Pathogens include aerobic and anaerobic bacteria including Group A Streptococcus (GAS, S. pyogenes), Clostridium perfringens, CA-MRSA, Klebsiella spp
  • Patient risk factors: Diabetes, steroids, burns, neutropenia
  • Clostridium septicum – gram positive, spore-forming anaerobe; trauma not needed for infection to occur; associated with GI and hematological malignancies
  • Clostridium causes myonecrosis through release of exotoxins
  • Clinical suspicion is important in guiding management including urgent surgical consultation – mortality ranges from 30-70% and increases with surgical delay

Management

  • Timely surgical exploration is essential to determine the extent of necrosis and debride all necrotic tissue
  • Repeat surgical exploration is typical 24-36 hours later and as needed
  • Empiric broad spectrum antibiotics should be started immediately and cover MRSA, streptococci, gram-negatives, anaerobes and narrow down pending cultures
  • Consider adding clindamycin to regimens if Group A Strep and clostridia species are suspected

image copyright Jorge Muniz @medcomic.com