What are the different types of gangrene?

Types of Gangrene

Gangrene can be classified into five main types: dry gangrene, wet gangrene, gas gangrene, Fournier's gangrene, and internal gangrene, each requiring distinct management approaches based on their pathophysiology and clinical presentation. 1, 2

Dry Gangrene

• Characterized by clear demarcation between viable and non-viable tissue
• Dry, shriveled appearance with minimal moisture
• Typically affects distal extremities
• Slow progression with minimal systemic symptoms
• Often occurs in patients with peripheral vascular disease or diabetes
• Management:
  • May be managed conservatively in select cases with potential for autoamputation
  • Elective amputation at appropriate level may be considered
  • Better prognosis compared to other types of gangrene 2

Wet Gangrene

• Characterized by edema, moisture, and bacterial infection
• No clear demarcation between viable and non-viable tissue
• Rapid spread of infection with systemic toxicity
• Foul odor from tissue
• Management:
  • Requires immediate surgical debridement of all necrotic tissue
  • Broad-spectrum antibiotics (vancomycin plus piperacillin-tazobactam, ampicillin-sulbactam, or a carbapenem)
  • Aggressive fluid resuscitation and intensive care monitoring
  • Higher mortality rate (20-50%) compared to dry gangrene 2

Gas Gangrene (Clostridial Myonecrosis)

• Most commonly caused by Clostridium perfringens, C. novyi, C. histolyticum, and C. septicum
• Characterized by gas formation in tissues (detected as crepitus or on imaging)
• Rapidly progressive with severe pain at the infection site
• Skin changes from pale to bronze to purplish-red
• Two main types:
  1. Traumatic gas gangrene: Associated with C. perfringens following trauma
  2. Spontaneous gangrene: Associated with C. septicum, occurs predominantly in patients with neutropenia and gastrointestinal malignancy
• Management:
  • Immediate surgical debridement
  • Antibiotic therapy with penicillin plus clindamycin (due to 5% of C. perfringens being clindamycin resistant)
  • Hyperbaric oxygen therapy remains controversial 1, 3

Fournier's Gangrene

• Necrotizing soft-tissue infection involving the scrotum, penis, or vulva
• Mean age of onset is 50 years
• Most patients have underlying diseases, particularly diabetes (80%)
• Three possible origins:
  1. Perineal skin (24%)
  2. Colorectal region (21%)
  3. Genitourinary tract (19%)
  4. Unknown origin (36%)
• Typically polymicrobial infection (Streptococcus, Staphylococcus, and E. coli commonly present)
• Characterized by intense pain, swelling, erythema, and rapid progression
• Management:
  • Prompt surgical debridement
  • Broad-spectrum antibiotics
  • Multidisciplinary approach involving general surgeons, urologists, and plastic surgeons 1

Internal Gangrene

• Affects internal organs such as intestines or gallbladder
• Often results from vascular occlusion or severe infection
• May present with organ-specific symptoms and systemic toxicity
• Management:
  • Surgical intervention to remove affected tissue
  • Treatment of underlying cause
  • Supportive care 2

Clinical Pearls and Pitfalls

1. Early recognition is critical: Delay in diagnosis and treatment significantly increases mortality, especially in wet gangrene and gas gangrene.

2. Don't confuse gas gangrene with non-clostridial infections: While both can present with gas in tissues, clostridial infections progress more rapidly and require more aggressive management.

3. Avoid premature closure of wounds: In traumatic wounds at risk for gangrene, delayed primary closure (4-7 days) is preferred to prevent creating an anaerobic environment.

4. Consider underlying conditions: Diabetes, peripheral vascular disease, and immunosuppression are major risk factors for gangrene development.

5. Antibiotics alone are insufficient: Surgical debridement remains the cornerstone of treatment for wet gangrene, gas gangrene, and Fournier's gangrene.

6. Autoamputation in dry gangrene: While sometimes considered in select cases, this approach should be limited to clearly demarcated, distal lesions in patients who are poor surgical candidates 4.

7. Recognize atypical presentations: Nontraumatic gas gangrene can occur without obvious wounds and may affect multiple extremities simultaneously 5.