Specific Organisms and Therapeutic Regimens
General recommendations and organism-specific therapeutic regimens for necrotizing fasciitis are provided below, including those for Streptococcus pyogenes, methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S aureus (MRSA), and Clostridium species. [1, 2] Of 469 Malaysian necrotizing fasciitis patients, the majority were monomicrobial, with Streptococcus species (19%), Pseudomonas aeruginosa (13%), and Staphylococcus species (13%) as the top three microorganisms isolated. [3]
One should recall that severe pain is an important clinical symptom separating necrotizing infections from more superficial ones. [4] Tachycardia and elevated levels of creatine kinase, C-reactive protein, and creatinine may also suggest necrotizing fasciitis.
Additional FDA-approved antibiotics for the treatment of acute bacterial skin and skin structure infections include oritavancin (Orbactiv), dalbavancin (Dalvance), and tedizolid (Sivextro). These agents are active against Staphylococcus aureus (including methicillin-susceptible and methicillin-resistant S aureus [MSSA, MRSA] isolates), Streptococcus pyogenes, Streptococcus agalactiae, and Streptococcus anginosus group (includes Streptococcus anginosus, Streptococcus intermedius, and Streptococcus constellatus), among others. For complete drug information, including dosing, see the following monographs:
General recommendations
Aggressive surgical intervention is the major therapeutic modality for patients with necrotizing fasciitis and should be performed as early as possible. [3, 5] Rarely, cobra and other snake bites may be linked with necrotizing fasciitis. In that case, the bite location, patient’s clinical features, and use of a specific antivenin as well as suitable antibiotics are pivotal for a favorable outcome. [6]
Periorbital necrotizing fasciitis requires interdisciplinary management and prompt high-dose intravenous antibiotic therapy. [7]
The antibiotic treatment of necrotizing fasciitis from Aeromonas infections can be difficult, as antibiotic resistance mechanisms may be involved. [8]
Antimicrobial therapy should continue for 48-72h after fever resolves, clinical improvement is evident, and no further surgical debridement is necessary
A Gram stain of the exudate demonstrates the presence of pathogens and can provide an early clue to the preferred treatment recommendations [1, 9]
Hyperbaric oxygen therapy may also be used, especially if the infection is due to anaerobic organisms [10, 11] ; however, its use should not delay pivotal surgical debridement; in addition, the value of hyperbaric oxygen therapy for treating those with necrotizing fasciitis has been questioned, [11] with evidence of to support or refute its value lacking [12, 13] One can consider combining appropriate intravenous antibiotic therapy with conservative surgery and hyperbaric oxygen and negative-pressure wound therapy in an effort to preserve tissues and control the advancing infection. [14] Vacuum-assisted closure can be used immediately after debridement. [15]
Patients with necrotizing fasciitis should be in an intensive care unit.
With urogenital necrotizing fasciitis (Fournier gangrene), prior to surgical resection of necrotic tissues, patients should receive intensive intravenous fluid replacement and parenteral broad-spectrum triple antimicrobial therapy, using a third-generation cephalosporin combined with metronidazole and/ or an aminoglycoside. [16]
Sometimes, classic triple therapy may be replaced with newer groups of antibiotics, such as piperacillin-tazobactam. [16] Clindamycin suppresses toxin production and also may be used.
Treatment should be guided by local antibiograms. Studies have documented that group A Streptococcus responds better to tedizolid, a second-generation oxazolidinone antibiotic, than to linezolid. A combination of doxycycline plus either ceftriaxone or cefotaxime has been recommended for necrotizing fasciitis due to Vibrio vulnificus. [17]
Streptococcus pyogenes
See the list below:
-
Penicillin G 2-4 million U IV q4-6h plus clindamycin 600 mg IV q8h
MSSA
See the list below:
MRSA or penicillin allergy
See the list below:
-
Vancomycin 15 mg/kg IV q12h or
-
Linezolid 600 mg IV q12h or
-
Daptomycin 6-8 mg/kg IV q24h or
-
Quinupristin/dalfopristin 7.5 mg/kg IV q12h
Clostridium spp
See the list below:
-
Clindamycin 600-900 mg/kg IV q8h or
-
Penicillin G 2-4 million U IV q4-6h
Guidelines
The Infectious Diseases Society of America recently updated their guidelines for the diagnosis and management of skin and soft tissue infections. For the full guidelines, see Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. [18, 19]
