The condition of gangrene is a serious one, primarily marked by loss of adequate supply of blood to the tissues of the body, ultimately resulting in its necrosis or death. Death of cell and tissue may target any part of the body, however, it has been typically observed in the extremities, such as the toes, fingers and hands. In the absence of a continuous supply of nutrient and oxygen rich blood, the cells within the body begin to fail in carrying out their normal function and finally give up.
Injury to the tissues, infection (mostly of bacterial origin) and presence of any underlying health ailment that inflicts damage to the blood carrying vessel structure form the three key underlying mechanisms that are responsible for initiation and development of irreversible tissue damage and life threatening condition of gangrene. The dead tissue, in turn, poses a significantly bigger risk of accentuating the infection. Both, dry and wet type of gangrene can be frequently seen in patients with diabetes.
Important Causes Of Gangrene In Diabetes
Damage To the Blood Vessel
As already explained, one of the causes of gangrene in the toes and fingers is linked with damaged blood vessels. The term ‘damaged’ refers to significantly curtailed or totally blocked blood vessels (arterial occlusion), as well as hardening of the walls of the blood vessels (atherosclerotic changes). As a result of restricted blood circulation to the extremities, such as the feet, the area becomes deprived of those cells (white blood cells) which aid in fighting off any infection.
This retards the rate at which wound healing occurs. In both, type 1 and type 2 diabetes, the raised level of sugar is capable of causing damage to the blood vessels and reducing blood supply.
Trauma To The Tissues
High level of blood glucose associated with diabetes mellitus also damages the nerves (known as peripheral neuropathy), especially the nerves in the lower extremities. Owing to the nerve damage, the transmission of sensation, particularly those of pain to the brain gets impaired.
The dullness or lack of sensation puts diabetic individuals at an increased risk of injuring the skin of their fingers or feet without having any realization (it mostly goes unnoticed in the feet region). The sore or foot ulcer formed takes an extended time to heal because of both, poor circulation of blood through the injured area as well as lesser number of defence cells. This increases the likelihood of further infection, ultimately leading to gangrene.
Bacterial infection also forms another causative factor that makes the diabetic individual more prone to developing gangrene. A notorious bacterial organism, Clostridium perfringes is often linked with gas gangrene; after it attacks the site of injury or sometimes, surgical wound.
Such type of infection is marked by noticeable skin discolouration and dryness along with the formation of skin blisters. The weakened immune system (seen in diabetes) further raises the risk of incurring serious infection, which later develops, into gangrene.
Effects Of Gangrene
The foremost clinical sign of gangrene is change in the skin colour of the affected area. As gangrene progresses or worsens, the pale colour changes into dark green or black. Tissue death may result in discharge along with foul odour. Swelling and inflammation resulting from the infection causes the local temperature of the area involved to be slightly elevated, and also leads to pain.