Patient handout

Necrotising fasciitis / Fournier’s gangrene / gas gangrene

PRODUCTION

1. Your condition

This handout is for necrotising fasciitis / fournier’s gangrene / gas gangrene. Your care team identified this based on: pain out of proportion to skin findings — cardinal early nf sign; lr+ ≈5-8 (stevens idsa 2014; wong 2003).

Other reasons your team may use this plan: rapidly extending erythema (>1 cm/h) + systemic toxicity (stevens idsa 2014; wses/sis-e 2018); hemorrhagic bullae, crepitus, "dishwater" exudate, anaesthesia of involved skin (stevens idsa 2014 — cardinal mid-late signs); inflow from id.cellulitis.core.v1 with necrotising-feature severity trigger (stevens idsa 2014).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

Medication	Starting dose	How	When	What it does
piperacillin-tazobactam	4.5 g IV q6h (extended infusion 4 h preferred in shock)	IV	q6h	Stevens IDSA 2014 — broad Gram-positive + Gram-negative + anaerobe + Pseudomonas; extended infusion for time-dependent killing; renal adjust CrCl < 40
vancomycin	25-30 mg/kg IV load × 1 → 15-20 mg/kg IV q8-12 h targeting AUC24 400-600 mg·h/L	IV	q8-12h (AUC-titrated)	Stevens IDSA 2014 + Rybak ASHP/IDSA 2020 — covers MRSA + CoNS + most Enterococcus; AUC-targeted dosing 2026 standard (PMID 32191793)
clindamycin	900 mg IV q8h	IV	q8h	Stevens IDSA 2014 — 50S ribosomal toxin suppression for Type II Strep pyogenes + Type III Clostridium (Eagle effect; Stevens JID 1988 PMID 3292661); critical — do NOT use macrolide alone; clindamycin-resistance in S. pyogenes rising regionally
meropenem	1 g IV q8h (2 g IV q8h for severe / immunocompromised / CNS extension)	IV	q8h	Stevens IDSA 2014 — replaces pip-tazo when ESBL risk or carbapenem preferred; broad-spectrum; pair with vanco + clindamycin; seizure risk in elderly + renal
imipenem-cilastatin	500-1000 mg IV q6h	IV	q6h	Stevens IDSA 2014 — equivalent carbapenem alternative; pair with vanco + clindamycin

Plan: NF empiric — piperacillin-tazobactam + vancomycin + clindamycin within 1 h (Stevens IDSA 2014; WSES/SIS-E 2018)

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

Clinical NF diagnosis (cardinal signs: pain out of proportion + hemorrhagic bullae OR crepitus OR rapid extension OR anaesthesia of involved skin) — STAT surgical activation within 1 h; mortality doubles per 6 h delay to OR (Stevens IDSA 2014; WSES/SIS-E 2018; Bilton AmJSurg 1998)(life-threatening)
Type II NF + shock + multi-organ failure — STSS toxin-mediated syndrome; clindamycin toxin suppression essential; IVIG Class IIa per Stevens IDSA 2014 (Darenberg 2003 RCT trend; Linnér 2014 observational OR 0.30); minimum 21 d duration for persistent toxemia (Stevens IDSA 2014)(life-threatening)
C. perfringens (post-traumatic) or C. septicum (spontaneous; colon-cancer-associated) myonecrosis + crepitus + hemorrhagic bullae + "dishwater" exudate + profound toxemia — penicillin G + clindamycin + emergent debridement; HBO transfer consideration if available; colonoscopy mandatory once stable for spontaneous C. septicum (Stevens IDSA 2014; Shupak 1995)(life-threatening)
Type III NF after seawater / raw oyster exposure OR cirrhosis with rapid-progression cellulitis — doxycycline + cefotaxime first-line; mortality > 50% if shock; surgical debridement + ICU + empiric within 1 h essential (Horseman J Infect 2011; Stevens IDSA 2014)(life-threatening)
Perineal / genital / perianal NF — almost always Type I polymicrobial; diabetes + obesity + immunocompromise predispose; emergent debridement + broad-spectrum + diverting colostomy considered for perineal extension; urology + colorectal surgery consultation (Stevens IDSA 2014)(life-threatening)
Type II monomicrobial Strep pyogenes (± S. aureus) NF — clindamycin essential for ribosomal toxin suppression (Eagle effect; Stevens JID 1988); macrolide alone is NOT acceptable; clindamycin-resistance in S. pyogenes rising regionally (Stevens IDSA 2014)
LRINEC ≥ 6 in patient with cellulitis or suspected SSTI — high suspicion for NF (LR+ ≈10 in Wong 2004 derivation cohort); do NOT delay surgical exploration for further imaging or labs; surgical clinical judgement always overrides (Wong CCM 2004; Bechar 2017)
Type I polymicrobial NF in diabetic or immunocompromised host — broaden anaerobic coverage; aggressive glycemic control; Fournier risk; lower OR threshold + lower second-look threshold; ID + endocrine consultation (Stevens IDSA 2014; IDSA Lipsky 2012)
Post-op (first debridement) persistent necrosis at second-look 24-48 h — mandatory repeat OR if necrosis advancing; antibiotics adjunct only; consider broaden empirics + reassess pathogen + tertiary debridement (Stevens IDSA 2014; WSES/SIS-E 2018)
NF + septic shock + multi-organ failure — routes bidirectionally to id.sepsis.core.v1 for SSC 2026 Hour-1 bundle + vasopressor management + ICU; surgical-source carryover maintained (SSC 2026; Stevens IDSA 2014)(life-threatening)

5. Follow-up

Physical / occupational rehab; plastic / reconstructive surgery for closure / grafting / amputation prosthesis; psychological sequelae after disfiguring debridement; OUD linkage if IDU; addiction medicine consult; diabetes optimisation; colon-cancer workup for C. septicum; community follow-up (Stevens IDSA 2014; AAP 2018)

6. Sources

Guideline: Stevens IDSA SSTI 2014 (Stevens, CID 2014 PMID 24973422) + WSES/SIS-E SSTI 2018 (Sartelli, World J Emerg Surg 2018 PMID 30564282) — co-canonical US + global surgical guidance. Supplemented by Wong LRINEC (CCM 2004 PMID 15241098), Eagle effect / Stevens clindamycin (Stevens JID 1988 PMID 3292661), Darenberg IVIG RCT (CID 2003 PMID 12884156), Linnér IVIG cohort (CID 2014 PMID 24928291), Horseman Vibrio (Int J Infect Dis 2011 PMID 21177133), Rybak ASHP/IDSA Vanco AUC 2020 (PMID 32191793), Bechar LRINEC meta (Ann R Coll Surg Engl 2017 PMID 28462647), Kumar antibiotic-delay (CCM 2006 PMID 16625125).