Pain out of proportion to clinical findings
Gas in tissues/crepitus (on exam or imaging)
Overlying tissue necrosis
Reduced sensation over affected area
Severe sepsis/septic shock
Suggested Antimicrobial Regimen
Obtain blood cultures x 2 sets and CK level in addition to other routine labs.
Imaging does not rule out the diagnosis of a necrotizing infection.
If suspected necrotizing fasciitis, need deep tissue specimen for C&S.
Surgical debridement is critical in cases of necrotizing fasciitis.
Clinically one cannot reliably distinguish between necrotizing cellulitis, fasciitis, or myonecrosis.
Type I Necrotizing Fasciitis
Polymicrobial infection involving Gram positive and Gram negative aerobes plus anaerobes
Type II Necrotizing Fasciitis
Monomicrobial infection involving Group A Streptococcus (Streptococcus pyogenes) and less often, Staphylococcus aureus.