What is Fournier's Gangrene
Fournier's gangrene is a life-threatening necrotizing fasciitis of the genital, perineal, or perianal regions caused by polymicrobial infection that requires immediate surgical debridement and broad-spectrum antibiotics to prevent mortality rates that can reach 20-50%. 1, 2
Definition and Pathophysiology
Fournier's gangrene is a rapidly progressive necrotizing soft tissue infection that begins when commensal bacteria gain entry into the perineum through anatomic portals, triggering an inflammatory cascade that leads to obliterative endarteritis with thrombosis of surrounding vessels. 1
- The vascular compromise causes tissue ischemia, which promotes further anaerobic bacterial proliferation and rapid tissue destruction. 1
- The infection can extend cranially to the abdominal wall and caudally to the legs via the superficial perineal fascia. 1
- This is typically a polymicrobial infection involving both aerobic organisms (Streptococcus species, Staphylococcus species, Escherichia coli) and anaerobic bacteria. 1
Epidemiology and Risk Factors
- Fournier's gangrene predominantly affects males with a male-to-female ratio of 42:1, with a mean age of presentation at 51 years. 1
- The overall incidence is approximately 1.6 cases per 100,000 males annually, accounting for less than 0.02% of all hospital admissions. 1
- Diabetes mellitus is the major predisposing factor, with obesity commonly associated. 1
- Other risk factors include conditions causing impaired host resistance and reduced cellular immunity, such as leukemia, HIV, alcoholism, and other immunocompromising conditions. 1, 3, 4
Common Sources of Infection
- Perianal and perirectal abscesses represent the most common etiology at 45.8% of cases. 1
- Urethral damage can provide a portal of entry for bacteria. 1
- Anal sphincter involvement with fecal contamination can serve as an infection source. 1
Clinical Presentation
The World Journal of Emergency Surgery emphasizes assessing for specific cutaneous manifestations in suspected cases: 2
- Erythema and tenderness to palpation 2
- Subcutaneous crepitations (indicating gas in tissues) 2
- Patches of gangrene 2
- Foul smell 2
- Purulence or wound discharge 2
Early manifestations are often subtle, making high clinical suspicion crucial for timely diagnosis. 3
Prognosis
- Mortality rates vary widely, ranging from 7.5% to as high as 88% in some studies, with contemporary series reporting 20-50% mortality. 1, 2
- The Fournier's Gangrene Severity Index (FGSI) should be calculated to predict outcomes, combining physiological parameters including temperature, heart rate, respiration rate, sodium, potassium, creatinine, leukocytes, hematocrit, and bicarbonate. 2
- The most significant modifiable risk factor associated with mortality is delay to surgical intervention. 3