Fournier Gangrene

Basics

Rapidly progressive necrotizing infection of perineum involving subcutaneous and fascial tissues and often muscle layers
Male gender (90% of cases)
Infection may spread at a rate of 1 inch per hr
Up to 75% of cases are initially misdiagnosed
Inadequate hygiene leads to scrotal skin maceration and excoriation:
- Portal of entry for bacteria in tissue
Once skin barrier is broken, polymicrobial flora spread along fascial planes of perineum
Colles fascia fuses with urogenital diaphragm, slowing propagation posteriorly and laterally
Anteriorly, Buck and Scarpa fascia are continuous, allowing rapid extension to anterior abdominal wall and laterally along fascia lata
Testes and urethra are usually spared
3 anatomic origins account for most cases:
- Lower urinary tract (40%): Urethral strictures, indwelling catheters
- Penile or scrotal (30%): Condom catheters, hidradenitis, balanitis
- Anorectal (30%): Fistulas, perirectal infections, hemorrhoids
Rarely, intra-abdominal sources such as perforating appendicitis, diverticulitis, or pancreatitis have produced Fournier gangrene by dependent contiguous spread

Infection by polymicrobial flora (mixed aerobic and anaerobic organisms; often of skin or bowel origin)
Mixed bacteria exert synergistic tissue-destructive effect
End-arterial thrombosis in subcutaneous tissues produces anaerobic environment
Bacterial toxins and tissue necrosis factors may contribute to clinical presentation
Rare cases have shown candidal infections causing Fournier gangrene
Risk factors:
- Trauma or surgery
- Diabetes
- Alcoholism (25–50% of cases)
- Other immunocompromised states
- Morbid obesity
- Abdominal surgery
- Use of sodium-glucose cotransporter 2 inhibitors
- Spinal cord injury
- Drug abuse (especially if injected directly into inguinal veins or the penis)
- Atherosclerosis

There's more to see -- the rest of this topic is available only to subscribers.