Table 3.

Necrotizing fasciitis—pathogens and treatments by anatomical site

Anatomical location	Predominant pathogens	Empiric antimicrobial therapy
Head/neck	Anaerobes	Ampicillin/sulbactam usually sufficient, though MRSA coverage should be considered, particularly in immunosuppressed or IV drug abusers
Abdomen/perineal	Gram negative, anaerobes	Cefepime + metronidazole OR an anti-pseudomonal carbapenem OR piperacillin- tazobactam
Lower extremity	Gram negative, anaerobes, Gram positive	In MRSA prevalent areas vancomycin PLUS cefepime + metronidazole OR an anti- pseudomonal carbapenem OR piperacillin-tazobactam
Surgical site	Variable depending on surgical site	In addition to anatomic location pertinent antimicrobials, if not already included, MRSA coverage should be considered in regions with high incidence