Dry gangrene

Background

Gangrene General Info

• A form of tissue necrosis characterized by critically insufficient blood supply leading to tissue death.
• Primarily divided into wet gangrene vs dry gangrene. Other, specific forms of gangrene include Fournier's gangrene, gas gangrene, and necrotizing fasciitis.
• Most commonly occur in distal extremities, clasically the feet.
• Main risk factors are diabetes, smoking, and peripheral arterial disease.

Clinical Features

• Usually due to peripheral arterial disease, but can also be caused by acute limb ischemia.
• Presents with dry, shrunken tissue, usually ranging from dark red to completely black, often with a clear line of demarcation between healthy and necrotic tissue. Typically not painful.

Differential Diagnosis

Foot infection

• Cellulitis
• Gangrene
  • Dry gangrene
  • Wet gangrene
• Trench foot
• Abscess
• Necrotizing soft tissue infections
  • Necrotizing fasciitis
  • Necrotizing myositis
  • Necrotizing cellulitis
• Osteomyelitis
• Diabetic foot infection
• Wet-sock erosions

Look A-Likes

• Ingrown toenail
• Peripheral artery disease
• Sporotrichosis
• Deep venous thrombosis

Evaluation

• History and physical examination are usually sufficient to make the diagnosis. If acute limb ischemia is suspected, consider a CTA of the affected limb and a vascular surgery consultation.

Management

• Infection rarely present, so management involves keeping the area clean and dry to prevent infection. Will usually auto-amputate in <6 months. Should be referred to vascular surgery as auto-amputation may not occur, and they may benefit from revascularization therapies to prevent further tissue death.
• If acute limb ischemia is present, embolectomy or surgical bypass may be required to restore flow.

See Also

• Gangrene