Gangrene Symptoms, Signs, and Diagnosis

A patient's symptoms will depend on the type of gangrene, the location of the gangrene (internal organs, skin, extremity, etc.), and how much the gangrene has progressed.

• In dry gangrene, the skin is hard and black or purplish. In earlier stages, the skin may be pale and either numb or painful.
• In wet gangrene, the affected area will be swollen with blisters oozing fluid; and the area may be red and warm with a foul odor.
• Gas gangrene causes severe pain, fever, and the skin will crackle like bubble wrap when pressed.
• Fournier's gangrene will cause redness and swelling in the genital area. Patients with gangrene affecting internal organs such as the gallbladder or intestines will typically be very sick with fever, low blood pressure, and severe pain.

Diagnosis can be made by a physician's physical exam and assessing bital signs, particularly when infection is involved. In addition, blood tests may be done to look for infection and diabetes. A portion of tissues may be removed (biopsy) and examined under a microscope to look for dead cells. X-rays, a CT scan, and MRI can also help make the diagnosis. Finally, an arteriogram may be done to evaluate the blood supply to the affected area. In this exam, dye is injected into an artery and an X-ray is used to evaluate if an artery is blocked. Samples from the gangrenous area might be sent to the laboratory to look for bacteria.