Gangrene: Causes, Signs & Treatment

In my years of practice, few conditions demand as much urgency as gangrene. 

Patients often arrive late, having waited days or even weeks, hoping the “wound” that is blackened skin with foul smell and severe pain would somehow “resolve on its own”. It rarely does. And that delay is what costs people their limbs.

This post is my attempt to cut through the confusion. What is gangrene, really? Who is at risk? And most importantly, how do you know when it’s time to stop waiting and see a doctor.

What Is Gangrene?

Gangrene is the death of body tissue, caused by a loss of blood supply. It most commonly affects the extremities: toes, feet, fingers, and nails. But it can involve the intestines, gallbladder, and other internal organs too.

When blood flow to a part of the body stops, whether due to a blocked artery, infection, or injury, the tissue begins to die. If left untreated, it can spread and become life-threatening.

There are several types, and here’s a summary:

Dry gangrene is most common in patients with PAD or diabetes. The affected area becomes dry, shrivelled, and dark with brownish-black discolouration. There is often a clear line of demarcation between living and dead tissue. It develops slowly and is relatively less life-threatening but still requires urgent medical attention.

Wet gangrene is far more dangerous. It involves bacterial infection of the dead tissue, leading to swelling, blistering, foul discharge, and rapid spread. This is a surgical emergency. Wet gangrene can become life-threatening within hours if not treated.

Gas gangrene is caused by the bacterium Clostridium perfringens, which produces gas within tissues. It is rare but devastatingly fast-moving. 

Clinical tip: If pressing on the skin feels like a crackling sensation, get to a vascular specialist immediately.

Fournier’s gangrene is a particularly severe form involving the genital and perineal region, seen more often in diabetic and immunocompromised individuals. It carries a high mortality rate and requires aggressive, emergency surgery.

Meleny’s gangrene is progressive bacterial synergistic gangrene, a rare form that usually occurs after surgery or trauma.

Internal gangrene occurs when the blood supply to an internal organ, such as the intestines or gallbladder, is cut off, due to a hernia, bowel obstruction, or vascular blockage. It presents with severe abdominal pain, fever, nausea, or vomiting. With no visible skin changes, diagnosis is often delayed, and it is a life-threatening condition requiring urgent surgery.

Causes Of Gangrene

Gangrene progresses gradually and is the endpoint of an underlying circulation issue. The most significant causes include:

Diabetes mellitus is the leading cause in India and globally. High blood sugar causes circulation issues, starving the nerve endings of oxygen and nutrients. This means patients often can’t feel an injury due to peripheral neuropathy. A small cut or blister can progress to a large ulcer. Impaired blood supply causes impaired healing, and the wound becomes gangrene or a diabetic foot.

Peripheral arterial disease (PAD) is the narrowing or blockage of arteries supplying the limbs. Reduced blood flow means impaired healing because the tissue is already deprived of oxygen. Any injury can increase the risk of foot gangrene.

Smoking is the most potent accelerator of arterial disease because it causes vascular inflammation. It increases your risk of developing gangrene by about 3-4 times. I’ve seen patients in their 40s with limb-threatening ischaemia who would have been spared years of suffering if they had stopped smoking earlier.

Chronic kidney disease, heart failure, and immunosuppression, including patients on steroids or chemotherapy, all impair healing and immune response, making gangrene more likely and more severe.

Trauma and crush injuries can directly cut off blood supply to a limb, triggering rapid-onset gangrene, even in otherwise healthy individuals.

Gangrene: When To See A doctor?

The following gangrene warning signs mean you must consult a vascular specialist immediately:

• A wound or ulcer on the foot or leg that is not healing even after 4-6 weeks
• Skin that is turning dark, brown or black
• Persistent coldness or numbness in a foot or toe
• Redness, swelling, or warmth around a wound that is spreading
• Foul-smelling discharge from a wound
• Fever, chills, or confusion

Important: Pain that stops in a previously painful limb indicates complete nerve death: a warning of progression, not relief.

How Is Gangrene Treated?

Treatment depends on the type, extent, and underlying cause, but the guiding principle is always: restore blood flow, control infection, and remove dead tissue.

Revascularisation

Restoring blood supply or revascularisation, through angioplasty, stenting, or bypass surgery, is the cornerstone of vascular gangrene treatment. 

This is where endovascular techniques work best: many cases that previously required open surgery can now be managed with minimally invasive scarless techniques.

Debridement

Surgical removal of dead and infected tissue or debridement is often needed multiple times before a wound is clean enough to heal.

Antibiotics 

When infection is present, antibiotics are prescribed, but they cannot replace surgical or interventional treatment where indicated. Self-medication is strongly discouraged, as inappropriate use can lead to antimicrobial resistance and adverse reactions, causing discomfort rather than improving the situation.

Hyperbaric oxygen therapy is an adjunct used in select cases to improve tissue oxygenation and support healing.

Amputation 

Amputation is required when tissue is non-viable, extensively infected, or limb salvage is no longer possible. 

Amputation is considered only when limb salvage is no longer possible—due to extensive tissue death, uncontrolled infection, or when restoring blood flow will not result in healing.

The decision depends on:

• Depth of involvement (skin, muscle, bone)
• Extent of infection
• Adequacy of blood supply after revascularisation

In many cases, timely vascular evaluation can prevent amputation, and this assessment is best performed by a qualified vascular surgeon. Choose a specialist with a DrNB/MCh degree in Peripheral Vascular Surgery. 

Why Choose Dr Kartik Gupta For Gangrene Treatment

Dr Kartik Gupta (DrNB) is among the very few formally trained vascular surgeons in Nagpur and Central India. Here’s why patients trust his care:

• Gold Medalist in DrNB Vascular Surgery from the prestigious Sir Ganga Ram Hospital, New Delhi, India’s leading vascular centre.
• Over 10 years of clinical experience managing complex cases across rural and urban settings
• Fluent in Marathi, Hindi, and English, so patients can explain their concerns comfortably and understand their treatment options clearly.
• Conservative approach with focus on limb salvage: surgery is advised only when necessary

Dr Kartik Gupta is available at the CIIVES Department: Monday to Saturday, 9 am to 6 pm. For appointments call: 9270292937

If you or someone you love has diabetes and a non-healing wound, don’t wait for a crisis. Early assessment can mean the difference between saving a limb and losing it.

Gangrene is preventable, but only if you act in time.