Let's talk Nec Fasc! Necrotizing fasciitis can be devastating! While sometimes it is obvious, often it is more subtle and you are left with worrisome suspicion and no clear path forward. Today, we discuss some key factors of necrotizing fasciitis diagnosis and management. I don't cover this comprehensively–go to these review articles for that:
Review Papers
Types
- Type IV – candida or zygomycetes
- Vibro Vulnificus and Aeromonas Hydrophilia are usually categorized into Type III, but sometimes Type IV
- You can get Vibrio just from oysters or other raw seafood, either by consumption or cuts during preparation. Also from brackish water.
- Clostridium Septicum may have hematogenous spread from bowel in colon cancer or immunocompromise
- Risk factors for any type, but especially Type I and IV – diabetes or immunocompromise
- Can occur with or without skin break
- Can occur without sig. skin symptoms (cryptogenic)
- Be worried in post-op patients
Body Areas
Extremities
Ludwigs
Head/Neck
Fournier (Diabetics on SGLT2 inhibitors may be at additional risk beyond just DM)
We are covering NecFasc but it can also involve the muscle, i.e. necrotizing myosititis
Signs/Symptoms
Pain out of proportion
Fever (neither high nor low LR)
Hemorrhagic Bullae (LR+ 6)
Hypotension (LR+ 9.2)
Systemic Symptoms
Clinical Suspicion Determinants
- Skin+Systemic
- Rapidly progressing or worrisome skin
- Systemic with localized pain without significant skin findings
Always consider Pyoderma Gangrenosum
Labs
LRINEC Score
CRP, WBC, Hb, Na, Cr, Glucose
Not suitable to rule out necrotizing fasciitis
LRINEC ≥ 6 had sensitivity of 68.2% and specificity of 84.8%, while LRINEC ≥ 8 had sensitivity of 40.8% and specificity of 94.9%. LR+ 4.25, LR- 0.38 [PMID 29672405]
Gram Stain Correlates
POCUS
Linear probe over affected area
Gas or Deep fascial fluid (>=4mm)
CT Scan
Fascial edema, enhancement, or gas
MRI
Scalpel / Finger Test
Surgery Consultation
Approach to debridement in Necrotizing Fasciitis
Antibiotics
Meropenem 1 gm Q8 or 3.375 g every 6 hours or Piperacillin-Tazobactam 4.5 g every 8 hours
plus
Linezolid 600 mg IV Q12 (preferred) or Vancomycin 20-25 mg/kg load
plus
Clindamycin 600 to 900 mg intravenously [IV] every eight hours in adults
Suspected Vibrio or Aeromonas will require additions/substitutions
Hemodynamic Support
Operations
Aggressive and meticulous
IVIG
Perhaps only in Strep Toxic Shock Syndrome [29788397]
Hyperbaric
Hospital Plan for Every Body Area
- Foot
- Leg
- Buttocks
- Hand
- Arm
- Body
- Fournier
- Head/Neck
- Ludwigs
More on EMCrit
- Necrotizing fasciitis(Opens in a new browser tab)
- Toxic Shock Syndrome (TSS)(Opens in a new browser tab)
- Early suspicion of toxic shock syndrome(Opens in a new browser tab)
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Professor
Nassau University Medical Center
No conflicts of interest (coi).
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Had a surgical resident abbreviate “pain out of proportion” in a CT scan order, and the radiologist lost his mind thinking she wanted a CT scan to eval for POOP on the patient’s thigh.
nice!
Jacob D. Mace, DO
For the antibiotic recommendation, doesn’t Linezolid have anti-toxin properties similar to Clindamycin?
At my previous department we utilized Linezolid + Zosyn with the presumption that anti-toxins were covered with Linezolid.
Augusta Emergency Physicians
University of Virginia
Yes, that was mentioned in the podcast explicitly. I think the interesting part of the ? is do these anti-toxin properties obviate the need for the Clinda. I would say no, at least initially, I would probably still give the clinda and that is the rec from most of the current papers out there, but you may turn out to be right in the future.
Yes I agree with Scott. This is an issue I’ve wrestled with in the necrotizing fasciitis and toxic shock chapters that I’m in the process of updating now. For very sick nec fas / TSS patients I would favor initial therapy with dual toxin suppression (clindamycin and linezolid). They act at molecular different sites and may in theory be synergistic (one lab study suggested synergy but data is scant). Currently the clinical evidence is largely supportive of clindamycin, which makes me leery of just using linezolid. Once patients are turning the corner (often after ~24 hrs of initial resus) I… Read more »