Eschar
Encyclopedia
An eschar is a slough or piece of dead tissue
that is cast off from the surface of the skin, particularly after a burn injury
, but also seen in gangrene
, ulcer, fungal infections
, necrotizing spider bite wounds
, and exposure to cutaneous anthrax
.
Black eschars are most commonly attributed to anthrax, which may be contracted through herd animal exposure, but can also be obtained from pasteurella multocida
exposure in cats and rabbits. A newly identified human rickettsial infection, R. parkeri rickettsiosis
, can be differentiated from Rocky Mountain spotted fever by the presence of an eschar at the site of inoculation.
Eschar is sometimes called a black wound because the wound is covered with thick, dry, black necrotic tissue
.
Eschar may be allowed to slough off naturally, or it may require surgical removal (debridement
) to prevent infection, especially in immunocompromised patients (e.g. if a skin graft is to be conducted).
If eschar is on a limb, it is important to assess peripheral pulses of the affected limb to make sure blood and lymphatic circulation is not compromised. If circulation is compromised, an escharotomy
, or surgical incision through the eschar, may be indicated.
An escharotic is a substance that causes tissue to die and slough off. Examples include acids, alkalis, carbon dioxide, metallic salts or sanguinarine
.
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
that is cast off from the surface of the skin, particularly after a burn injury
Burn (injury)
A burn is a type of injury to flesh caused by heat, electricity, chemicals, light, radiation or friction. Most burns affect only the skin . Rarely, deeper tissues, such as muscle, bone, and blood vessels can also be injured...
, but also seen in gangrene
Gangrene
Gangrene is a serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies . This may occur after an injury or infection, or in people suffering from any chronic health problem affecting blood circulation. The primary cause of gangrene is reduced blood...
, ulcer, fungal infections
Mycosis
A mycosis is a fungal infection of animals, including humans. Mycoses are common, and a variety of environmental and physiological conditions can contribute to the development of fungal diseases...
, necrotizing spider bite wounds
Brown recluse spider
The brown recluse spider or violin spider, Loxosceles reclusa, is a member of the family Sicariidae . The spider has a venomous bite....
, and exposure to cutaneous anthrax
Anthrax
Anthrax is an acute disease caused by the bacterium Bacillus anthracis. Most forms of the disease are lethal, and it affects both humans and other animals...
.
Black eschars are most commonly attributed to anthrax, which may be contracted through herd animal exposure, but can also be obtained from pasteurella multocida
Pasteurella multocida
Pasteurella multocida is a Gram-negative, non-motile coccobacillus that is penicillin-sensitive and belongs to the Pasteurellaceae family . It can cause avian cholera in birds and a zoonotic infection in humans, which typically is a result of bites or scratches from domestic pets...
exposure in cats and rabbits. A newly identified human rickettsial infection, R. parkeri rickettsiosis
Rickettsiosis
A rickettsiosis is a disease caused by intracellular bacteria.It has been predicted that global warming may lead to greater incidence.-Examples and causative organisms:Rickettsioses can be divided into a spotted fever group and typhus group ....
, can be differentiated from Rocky Mountain spotted fever by the presence of an eschar at the site of inoculation.
Eschar is sometimes called a black wound because the wound is covered with thick, dry, black necrotic tissue
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
.
Eschar may be allowed to slough off naturally, or it may require surgical removal (debridement
Debridement
Debridement is the medical removal of a patient's dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue...
) to prevent infection, especially in immunocompromised patients (e.g. if a skin graft is to be conducted).
If eschar is on a limb, it is important to assess peripheral pulses of the affected limb to make sure blood and lymphatic circulation is not compromised. If circulation is compromised, an escharotomy
Escharotomy
An escharotomy is a surgical procedure used to treat full thickness circumferential burns. Since full thickness burns are characterized by tough, leathery eschar, an escharotomy is used primarily to combat compartment syndrome...
, or surgical incision through the eschar, may be indicated.
An escharotic is a substance that causes tissue to die and slough off. Examples include acids, alkalis, carbon dioxide, metallic salts or sanguinarine
Sanguinarine
Sanguinarine is a quaternary ammonium salt from the group of benzylisoquinoline alkaloids. It is extracted from some plants, including bloodroot , Mexican prickly poppy Argemone mexicana, Chelidonium majus and Macleaya cordata. It is also found in the root, stem and leaves of the opium poppy but...
.