Coagulation necrosis: description, causes and treatment

Necrosis is an irreversible process of destruction and death of cells, human organs, which is caused by the action of pathogenic bacteria. The cause of development can be: exposure to high temperatures (with burns), chemical or infectious agents, mechanical damage. Necrosis may be coagulative (dry) or colliquated (wet). In the article, we will consider in more detail the causes of the appearance of dry necrosis, as well as the ways of its treatment.

What is coagulation necrosis?

Dry necrosis often affects organs that are rich in protein, but with a low liquid content. These include:

• Kidney;
• Adrenal glands;
• spleen;
• Myocardium.

The death of cells of organs occurs due to insufficient blood supply and enrichment with oxygen as a result of thermal, chemical, mechanical, toxic damage. As a result, the dead cells dry up, and the process of mummification takes place. Dead cells are delineated from the living by a clear line.

Causes of development of dry necrosis

Dry necrosis is formed if:

• There was a process of violation of the blood supply of a specific site of a certain organ, as a result, there was a deficit of oxygen and the necessary nutrients;
• The disease developed gradually;
• The affected parts of the organs did not have enough fluid (fat layer, muscle tissue);
• There were no pathogenic microbes in the affected area.

People with strong immunity and malnutrition are more likely to develop dry necrosis.

Coagulation necrosis: a mechanism of development

Due to inadequate oxygen saturation of cells and disruption of blood supply, the process of coagulation and compaction of protoplasm occurs, then the affected area dries up. Damaged parts have a toxic effect on neighboring living tissues.

The affected area has a characteristic appearance: the dead cells are delineated by a clear line and have a pronounced yellow-gray or clay-yellow color. This area becomes denser with time. At a cut it is possible to notice, that fabrics absolutely dry, have curdled consistence, thus the drawing is indistinct. As a result of the decay of the nucleus, the cells look like a mass of a homogeneous cytoplasm. Further, with the development of necrosis and inflammation, one can observe the rejection of dead tissues. If the disease affects the auricle or bones of a person, a fistula is formed. However, the mechanism of development of coagulation necrosis is not yet fully understood.

Types of coagulation necrosis

Coagulation necrosis includes several types:

• Infarction is the most common type. It develops as a result of ischemic disease. Does not develop in the brain tissues. With a heart attack, complete regeneration of damaged tissues is possible.
• Waxy (Zeckerovsky) - develops as a result of severe infectious damage. The disease affects the muscle tissue, often leading to the muscles of the hip and anterior abdominal wall. The development of necrosis provokes previously transmitted diseases, such as typhus or typhoid fever. The affected areas are gray.
• Caseous necrosis is a specific kind of disease. A companion of tuberculosis, syphilis, leprosy, leprosy, Wegener's disease . With this type of necrosis, the stroma and parenchyma die (fibers and cells). The peculiarity of this disease is that, in addition to dry areas, pasty or curdled granulomas are formed. Affected tissues have a bright pink color. Caseous necrosis is one of the most dangerous species due to the fact that it is capable of "killing" huge tracts.
• Fibrinoid is a disease in which connective tissue is damaged. Necrosis develops in autoimmune diseases, for example, with lupus or rheumatism. The disease most affects the smooth muscles and fibers of blood vessels. Fibrinoid necrosis is characterized by a change in the normal state of collagen fibers and the accumulation of necrotic material. In microscopic examination, the affected tissue is similar to fibrin. In this case the dead ones have a bright pink color. Sites affected by fibrinoid necrosis contain a large amount of immunoglobulin, as well as fibrin and collagen degradation products.
• Fat - the disease is formed as a result of bruises and hemorrhages, as well as destruction in the tissues of the thyroid gland. In case of necrosis, the peritoneum and mammary glands are affected.
• Gangrenous - it can be dry, wet, gas. Bedsores in bedridden patients also refer to this type of necrosis. Most often, the disease is caused by bacteria that enter the affected areas.

Dry gangrene as a type of coagulation necrosis

Dry gangrene is a disease in which skin necrosis, which comes into contact with the external environment, develops. As a rule, any microorganisms do not participate in the development of the disease. Dry gangrene often affects the limbs. Damaged tissues have a dark, almost black color and a brightly outlined contour. The color changes under the influence of hydrogen sulphide. This is because the hemoglobin pigments are converted to iron sulphide. Dry gangrene develops under the following conditions:

• At thrombosis of arteries and atherosclerosis of extremities.
• When exposed to extremities of high or low temperatures (with burns or frostbite).
• With the development of Raynaud's disease.
• In the presence of infections, for example with typhus.

Treatment is carried out only by surgical removal of dead tissue.

Wet gangrene

Wet gangrene is a disease that develops when a bacterial infection hits damaged tissue. The disease affects organs that are rich in moisture, can occur on the skin, but often spread to internal organs. Wet gangrene affects the intestines (with arterial obstruction) and the lungs (arises as the consequences of pneumonia).

Often, the disease occurs in children, since their immunity to infection is more malleable with the formation of gangrene. The soft tissues of the cheeks and perineum are affected. This disease is called water cancer. The affected areas become very swollen and have a dark color. There is no demarcation contour, so the disease is difficult to surgically treat, since it is difficult to determine where the affected tissues end. Gangrenous areas have a very unpleasant odor, and the disease often leads to death.

Gas gangrene and pressure sores

Gas gangrene in its manifestations is very similar to wet, but the causes of development are different. This type of gangrene develops if bacteria of the species Clostridium perfringens enter infected tissues that begin with necrosis and actively multiply. Bacteria in the process of their life emit a specific gas, which is found in the affected tissues. Mortality in this disease is very high.

Bedsores belong to one of the types of gangrene, in which the process of tissue death occurs. Diseases are most prone to recumbent patients, since certain areas of the body due to prolonged immobilization are under pressure and do not receive the necessary substances along with blood. As a result, skin cells die. The region of the sacrum, heels, thigh bone are most affected.

Diagnosis of coagulation necrosis

To diagnose "coagulative necrosis," if the lesions are superficial, the doctor should take blood and a sample of the damaged tissue for analysis.

In case there is a suspicion of necrosis of organs, the examination is more extensive. For this you need:

• Carry out radiography. This study is especially relevant if there is a suspicion of gas gangrene.
• Carry out a radioisotope study. It is prescribed if the X-ray did not reveal any changes (at the initial stage of the disease). A radioactive substance is introduced into the human body. If there is a necrotic change in the tissues of the organ, it will be highlighted by a dark spot.
• Conduct a CT scan. It is carried out if there is a suspicion of the defeat of bones.
• Conduct an MRI. The most effective method of research, as it shows even minor changes associated with a violation of blood circulation.

Complications of necrosis

Necrosis is the "death" of damaged organs and tissues. Therefore, its various types, such as infarction, necrosis of the brain, kidneys or liver, can lead to death of a person.

Also, extensive necrosis can lead to serious complications, for example, with multiple bedsores, a dangerous infection can be attached. Dead tissues release into the body the products of their disintegration, thus leading to toxic complications. Even lighter forms of the disease can lead to unpleasant consequences, for example, scar formation in the myocardium or the formation of a cyst in the brain.

Treatment of necrosis

Treatment of necrosis begins with the definition of its type, evaluation of the damage caused to it and the detection of concomitant diseases.

When diagnosing dry skin necrosis, local treatment is prescribed:

• Treatment of affected areas with greenery.
• Skin cleansing with antiseptics.
• Applying a dressing with a solution of "Chlorhexidine".

The patient is prescribed medication and surgical treatment to restore normal blood circulation, including in affected areas. To remove dead cells, surgery is most often performed to resect the affected areas. Amputation of the limbs is made in order to protect healthy areas from the spread of the disease.

Dry necrosis of internal organs is treated with the use of anti-inflammatory drugs, vasodilators, chondroprotectors. In the case of ineffective therapy, surgical treatment is performed.