Gangrene

Gangrene refers to the death of the tissue in any particular area of the body caused by the loss of blood supply. Though gangrene can occur in any part of the body, it normally affects toes, fingers, feet and hands. Infections, vascular disease, diabetes, injury and weakened immunity are some of the causes of gangrene.

Types of gangrene

Dry gangrene: Dry gangrene involves lack of blood supply due to cell death and necrosis. This condition is not associated with infection and develops gradually over a period of time. Patients with diabetes, atherosclerosis and other blood vessel diseases are most likely to develop dry gangrene. Those suffering from injuries, burns, frostbite and any other arterial trauma are also prone to dry gangrene.

Symptoms of dry gangrene

• Affected area feels numb and cold.
  
• Does not show any signs of healing due to interrupted blood supply and necrosis (un programmed cell death).
  
• Patients may or may not have pain.
  
• Color changes gradually from red to brownish red and eventually becomes black.
  
• Skin becomes dry, scaly, shriveled and finally falls off the body if not treated in time.
  
• On very rare occasions, the onset of dry gangrene may be sudden which may be caused by an immediate loss of arterial blood supply. In such a case, the affected area turns pale or bluish and then starts withering away.

Wet gangrene: Bacterial infection, loss of blood supply due to swollen tissues and gas production are some of the causes of wet gangrene. Wet gangrene spreads very quickly and in no time turns into sepsis. It restricts the white blood cells from reaching affected area, allowing the bacteria to feed on the surrounding muscles. Hence wet gangrene is a medical emergency and requires immediate treatment.

There are few variations to wet gangrene and one of them is gas gangrene. The bacterial organism called Clostridium perfringens causes gas gangrene. The bacteria present in the site releases toxins and produces gas bubbles in the dead tissues affecting not only the local site, but adjoining tissues and muscles. Though gangrene normally occurs on external parts of the body like hands, toes and legs, it can also attack internal organs like gallbladder, intestines and appendix. This condition is called internal gangrene. Internal organs may develop hernia, get strangulated and as a result do not receive sufficient blood supply causing gangrene.

Fournier gangrene is the gangrene that occurs in the male genital area due to an infection or urinary tract infection. Red skin, swelling, tenderness associated with pain are some of the symptoms of Fournier gangrene.

Necrotizing fasciitis is a type of wet gangrene that is caused by bacterial infection, affecting the deep layers of skin. It progresses rapidly and starts eating up the flesh in the body.

Symptoms of wet gangrene

• The site at which gangrene has occurred becomes swollen and painful. The skin in that area gets discolored.
  
• Pus, oozing of fluid and foul smell in the affected area.
  
• Fever indicating sepsis.
  
• If it is a gas gangrene, along with above mentioned symptoms, patient may experience increased heartbeat and vigorous breathing as toxins enter the blood stream. When the wound is pressed, there will be a slight crackling noise as there is a gas beneath the skin.

Causes of gangrene

The first and the primary cause of gangrene is complete loss or insufficient supply of blood to the tissue. When there is no blood supply, the required oxygen does not reach the cells allowing them to decay and die. Bacterial infections, trauma, damaged blood vessels, and blood vessel disease like atherosclerosis are some of the causes that restrict the blood supply leading to gangrene. Surgery wounds, frost bites, severe burns are typical breeding sites for bacteria causing infection and gangrene.

Diagnosing gangrene

Doctor will conduct a thorough physical examination and look for the symptoms like discoloration, pus, shrinking of skin, odor to determine the type of gangrene. If it is a wet gangrene, further tests like blood test, blood culture and tissue cultures are carried on to find out about the white blood cell count and the kind of bacteria causing the issue. This helps the doctors to decide on the right course of antibiotics. Imaging studies like X-ray, MRI and CT scan are done to determine the spread of gangrene.

Gangrene Treatment

Treatment approach varies depending upon the type of gangrene. However, whatever be the type of gangrene; it should be brought to the notice of the medical practitioner at the earliest to prevent it from spreading. In case of dry gangrene, firstly, doctor will remove the dead tissues from the affected area surgically. Next, he will try to correct the destroyed blood vessels to smoothen the blood flow. Patient will be administered antibiotics to curtail the spread and will also be given some anti blood clotting drugs.

Wet gangrene is a medical emergency and once diagnosed, treatment should start as quickly as possible. Debridement procedure is normally adopted to treat wet gangrene. Debridement refers to the removal of dead and decaying tissues from the affected site. Antibiotics are administered to control the infection and pain killers are given to relieve the patient from pain. In worst cases surgeon may have to amputate, where the affected limb will be separated from the body to prevent further deterioration. Gas gangrene is a deadly disease. Though it is treated in the same way as mentioned above, it necessitates swift action when compared to all other gangrenes. The infection can spread and enter the blood stream very quickly causing organ failures.

There is also an alternate therapy called hyperbaric oxygen therapy that is gaining momentum to treat gas gangrene. This process involves exposing the patient to 100% oxygen at inflated pressure for 90 to 120 minutes, three times a day for 2 days. Then the frequency will be brought down as per the patient's requirements. This therapy stimulates the cell growth, enhances the white blood cell count thereby regulating the infection and increasing the blood flow to areas affected by the arterial blocks.

Preventing gangrene

• Seek prompt treatment for any kind of external wound, cut or injury before the site is attacked by infection.
  
• Diabetics should keep their sugar levels under control as they are at higher risk. Those with vascular diseases and low immunity levels should be extremely cautious and vigilant about the signs of infection like pus, oozing, discoloration, swelling and pain. They should take good care of their fingers, toes and feet and go for frequent health checkups to rule out any adverse health condition.

Dry gangrene is easily treatable provided there is no infection associated with it. Chances of recurrence are higher in diabetes patients. The outlook for wet gangrene is poor and patients with severe infection and sepsis may also lose their life, if treatment is not initiated in time. It requires an aggressive treatment and patients with wet gangrene may end up with amputation.

Ergotism

Ergotism is a condition with symptoms of convulsion and gangrene due to ergot poisoning. It usually occurs because of the toxic alkaloids produced by the Claviceps Purpurea fungus which affects rye, barley, wheat and other cereals. The convulsion occurring owing to Ergotism will include muscle spasms, nausea, vomiting, delusions, hallucinations, crawling sensations on the skin or intense burning sensation on the skin, diarrhea, paresthesia (tingling or pricking sensation on the skin) and headaches. Other symptoms of Ergotism include gangrene due to vasoconstriction of the extremities resulting in local stagnant anoxia - occurring in toes and fingers. During the mediaeval times, ergot poisoning had taken a great toll and monks belonging to the Roman Catholic order of the St.Anthony provided effective treatment - earning the disease a sobriquet 'St.Anthony's Fire' or 'Holy Fire'.

Ergot alkaloids are derivatives of Lysergic Acid Diethylamide (LSD), and ergotism sometimes results in hallucinations of bright colors, changes in space, Formication (insects crawling under the skin) and images of marauding animals.

Recently Ergotism, Ergotoxicosis ensues after high doses of ergot alkaloids such as Ergotamine tartrate (Cafatine) and Dihydroergotamine. If it is a mild manifestation, symptoms fade away after stopping the offending drug. But severe cases can be fatal.

Buerger's Disease

Buerger's disease (thromboangitis obliterans) is characterized by inflammation of the blood vessels in the legs. This leads to restricted blood flow. Over time it can lead to gangrene. Buerger's disease is usually noticed in men in the age group of 20 - 40 years. This condition has been strongly associated with smoking. Heavy smokers, especially those who have started at a young age are at higher risk.

What may begin as reduced blood supply to the limbs may later affect blood vessels in other parts of the body. There is decay in the tissues of the feet due to lack of blood. The limbs may turn white or blue as in the case of persons affected by Raynaud's disease. There may be numbness or tingling sensation in the limbs. There may be enlarged red surface veins. It is essential to treat Buerger's Disease promptly lest it lead to infection of the legs and gangrene. Patients suffering from Buerger's Disease must quit smoking.