Presence of gas in soft tissue (on radiographic imaging)* |
Polymicrobial (gram-positive cocci, gram-positive rods, gram-negative cocci, and gram-negative rods) |
Necrotizing fasciitis type I (polymicrobial) |
Necrotizing cellulitis: Nonclostridial anaerobic (crepitant) cellulitis |
Gram-positive rods |
Acute clinical presentation |
- Clostridial myonecrosis (gas gangrene)
|
- C. perfringens – Traumatic
|
- C. septicum – Spontaneous
|
- C. sordellii – Gynecologic
|
Indolent clinical presentation |
- Clostridial (anaerobic) cellulitis
|
- C. perfringens – More common
|
- C. septicum – Less common
|
Absence of gas in soft tissue (on radiographic imaging)* |
Gram-positive cocci |
Necrotizing fasciitis type II (monomicrobial) |
- Group A Streptococcus or other beta-hemolytic streptococci
|
- Staphylococcus aureus (methicillin-sensitive [MSSA] or methicillin-resistant [MRSA])
|
Necrotizing myositis due to group A Streptococcus or other beta-hemolytic streptococci |
Gram-negative rods |
Aeromonas species – Freshwater exposure |
Vibrio species – Saltwater exposure |