What is necrosis?
Necrosis is the pathological, i.e. pathological, destruction of cells, cell groups or tissue. Within a cell, this leads to clumping of DNA and cell swelling. The cell bursts and cellular components are released, which cause inflammation in the surrounding tissue. Necrosis can be caused by many different factors, such as extreme temperatures, toxins, circulatory disorders, radiation, infections with pathogens or mechanical influences. Necrotic tissue is either replaced by the original tissue (heals) or scar tissue develops.
Associated symptoms
The main symptom of necrosis is the externally recognizable yellowish-black discoloration of the skin. In addition to this usually very impressive symptom, however, other symptoms can also occur which confirm the suspicion. In the case of necrosis, the death and bursting of cells results in the release of inflammatory mediators, such as the tumor necrosis factor (TNF).
This subsequently leads to an inflammatory reaction of the surrounding tissue. This can lead to reddish swelling, pain, a feeling of tension and warmth around the necrosis. The entry of pathogens, for example bacteria, can cause the necrosis to liquefy and release wound secretions and pus.
If the pathogens spread into the blood system and have a systemic effect on the body, fever, chills, nausea and vomiting can also occur. The latter symptoms are particularly evident in necroses of the internal organs, such as the gall bladder, pancreas or appendix. Whether and to what extent pain occurs during necrosis depends on the cause and the individual patient.
Acute necrosis, for example due to a sudden vessel occlusion in the leg or necrosis of the abdominal organs, usually causes severe pain in the affected area. The main reason for this is the acute lack of oxygen. In the case of chronically progressive diseases or necrotic decubitus, the pain is often so slight that the necrosis is not even noticed. This is mainly due to the fact that necrosis begins very slowly and patients often have a reduced sensation in the skin (for example, in diabetes).
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