Fournier gangrene
Fournier gangrene is a rapidly progressive polymicrobial necrotizing fasciitis of the perineum and genitalia, usually arising from a perianal, urethral, or scrotal skin breach. The diagnosis is clinical, confirmed at surgical exploration, and first-line treatment is immediate broad-spectrum intravenous antibiotics paired with emergent, repeated surgical debridement.
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What this article covers
- Overview
Fournier gangrene is a rapidly progressive, polymicrobial necrotizing fasciitis confined at onset to the perineum, scrotum, penis, or vulvar region, spreading along fascial planes rather than through skin or muscle.
- Epidemiology
Sex distribution: occurs overwhelmingly in men, whose confluent scrotal, perineal, and penile fascia provide an uninterrupted plane for spread; uncommon in women, in whom it arises from a vulvar, perineal, or episiotomy source.
- Risk factors
Diabetes mellitus: the most common comorbidity, impairing neutrophil function and microvascular perfusion at the wound.
- Pathophysiology
Infection begins when gut or genitourinary flora cross a breached perianal, urethral, or scrotal barrier and reach the superficial fascia.
- Clinical features
Time course: onset over 1 to 7 days with vague perineal or scrotal pain and swelling, then rapid deterioration over hours as necrosis and systemic toxicity set in.
- Differential diagnosis
Cellulitis or erysipelas of the scrotum/perineum: shares erythema and tenderness, but pain is proportionate to exam, there is no crepitus or bullae, and it resolves with antibiotics alone.
- Diagnosis
What establishes the diagnosis: a clinical diagnosis confirmed at surgical exploration, where grey, non-bleeding fascia that fails to resist blunt dissection and foul-smelling discharge confirm the…
- Management
First, resuscitate as for sepsis: two large-bore intravenous lines and balanced crystalloid 30 mL/kg IV over the first 3 hours for hypoperfusion, then reassess with dynamic measures of fluid…
- Complications
Sepsis and septic shock: the leading cause of early death, driven by ongoing toxin release from unresected necrotic tissue.
- Prognosis
Mortality remains high: reported rates of 20 to 40% persist despite aggressive treatment, driven chiefly by delay to debridement and extent of disease at presentation.
- Prevention
Prompt drainage of perianal and perirectal abscess: treating the common antecedent source before it tracks into the fascia prevents many cases of anorectal origin.
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Related articles
- Necrotizing fasciitis
Necrotizing fasciitis is a rapidly progressive, life-threatening infection of the subcutaneous tissue and superficial fascia driven by vessel thrombosis and bacterial exotoxin production. The hallmark is pain out of proportion to visible skin findings, with crepitus, bullae, and woody induration in advanced disease. Diagnosis is confirmed by direct surgical exploration; the LRINEC score aids risk stratification. Treatment is emergent surgical debridement combined with broad-spectrum empiric antibiotics.
- Cellulitis
Cellulitis is a nonpurulent, spreading infection of the deep dermis and subcutaneous fat, usually caused by beta-hemolytic streptococci, diagnosed clinically and treated with antibiotics alone since there is no collection to drain.
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- Septic shock
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- Type 2 diabetes mellitus
Type 2 diabetes is hyperglycemia from insulin resistance with progressive relative insulin deficiency, diagnosed by a hemoglobin A1c of 6.5% or higher, a fasting glucose of 126 mg/dL or higher, or a 2-hour oral glucose tolerance test value of 200 mg/dL or higher. First-line treatment is lifestyle modification plus metformin, with an SGLT2 inhibitor or GLP-1 receptor agonist added early for patients with atherosclerotic disease, kidney disease, or heart failure.