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Fournier gangrene
Fournier gangrene is necrotising fasciitis of the perineum, genitalia and perianal region; it is an emergency treated with resuscitation, broad-spectrum antibiotics and above all immediate, extensive surgical debridement of dead tissue, with repeat operations.
Why it matters in the exam
The exam shows a man with uncontrolled diabetes (the commonest risk factor), alcoholism or immunosuppression, with severe scrotal or perineal pain out of proportion to the findings, swelling, redness turning purple-black, crepitus and signs of sepsis. SGLT2 inhibitors have also been linked to cases of Fournier gangrene. The source may be colorectal (perianal abscess), urological (stricture, catheter, injury) or cutaneous. The infection is polymicrobial — aerobic and anaerobic bacteria together.
The diagnosis is clinical. CT can show gas and define spread, but it must not delay surgery in a patient with a clear picture. The LRINEC score helps when the picture is unclear, but a low score does not exclude it. The infection spreads along Colles fascia to the abdominal wall (Scarpa fascia) and the thighs, but the testes are usually spared because their blood supply comes from the testicular arteries in the spermatic cord and not from skin vessels. Mortality is in the range of 20 to 30 percent and rises with delayed surgery.
Treatment: fluids and haemodynamic support, broad-spectrum antibiotics at once (for example piperacillin-tazobactam or a carbapenem, together with vancomycin or linezolid, and clindamycin to suppress toxin production), and extensive surgical removal of all dead tissue with a return to theatre after 24 to 48 hours. When the perianal area is involved or there is ongoing faecal contamination — a diverting colostomy; when the urethra is involved — a suprapubic catheter. Later, reconstruction with skin grafts or flaps, sometimes with negative pressure wound therapy.
Key points
- Necrotising fasciitis of the perineum and genitalia.
- Diabetes is the commonest risk factor.
- Polymicrobial.
- Immediate and repeated debridement.
- Testes usually spared.
Summary table
| Topic | Point | Note |
|---|---|---|
| Risk factors | Diabetes, alcoholism, immunosuppression, SGLT2 inhibitors | Diabetes the commonest |
| Organisms | Polymicrobial, aerobic and anaerobic | — |
| Signs | Pain out of proportion, crepitus, skin necrosis, sepsis | Testes usually spared |
| Treatment | Immediate extensive debridement and broad antibiotics | Return to theatre after 24 to 48 hours |
| Diversion | Colostomy if the anus is involved; suprapubic catheter if the urethra is involved | According to spread |
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Sources
- EAU Guidelines on Urological Infections, 2025 edition — Fournier gangrene (necrotising fasciitis of the perineum and external genitalia)
- IDSA Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections, 2014 — Necrotizing fasciitis
- Campbell-Walsh-Wein Urology, 12th edition (2020) — Infections and Inflammation of the Male Genital Tract
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.