Typical pathological process: definition, signs, examples

Everything that happens in the human body is subject to certain laws. They act stereotypically regardless of the situation, so the body, in an attempt to protect itself from the "threat" in the form of medicine or vaccination, sometimes harms itself. Why is this happening? And how can you influence this process to turn it for yourself? Is there a concept of a typical pathological process, species combining properties? Scientists and doctors have been thinking about these questions for hundreds of years. They try to deduce patterns in the reactions of the body to analyze its work.

Definition

A typical pathological process is a cascade of successive reactions that arise in the body in response to an external or internal factor that disrupts the normal course of life processes. Any pathological process has such qualities as universality, stereotypedness, polyethyology, autochthonism, equifinality and clear ontogenetic dynamics.

Knowledge of the characteristics allows us to distinguish typical pathological processes from the whole abundance of reactions occurring in the body every minute.

The main characteristics of the pathological process

Typical pathological processes are characterized by the presence of six specific qualities.

1. Stereotype. The presence of the features of a typical process, regardless of the cause of its appearance and localization.
2. Versatility. Typical pathological process can be in the composition of different nosological units.
3. Polyethiologic. The etiologic factor of the disease performs only a starting role and is not permanent.
4. Autochthonism. The process's ability to develop independently, even when the etiologic factor ceases to function.
5. Equivalence. Different ways to implement the pathological process, which lead to the same development and resolution.
6. Ontogenetic dynamics. This improvement of the mechanisms of regulation and course of the pathological process.

Knowing these characteristics, you can identify any typical pathological processes. Examples of such phenomena: inflammation, fever, hypoxia, stress, shock. In addition, one can classify these processes as a tumor, thrombosis, atrophy and many others.

Inflammation

Inflammation is a typical pathological process, which is manifested by changes in blood circulation, increased vascular permeability in combination with cell proliferation and dystrophy of surrounding tissues. It is aimed at eliminating the pathogenic stimulus and restoring the function of tissues and organs.

Inflammation includes five mandatory components: fever, pain, swelling, redness, and impaired function. These signs of a typical pathological process can be used for diagnosis, as well as differentiation of nosological units. The mechanism of inflammation is common to all living organisms, including the simplest, regardless of the trigger factor and the structural features of the organism.

Any inflammation necessarily goes through three stages, which can be more or less pronounced. The first stage is alteration. It is associated with damage to tissues and cells of the body. The next, exudation, begins when fluid enters the damaged area from the vascular bed. And the last stage is proliferation. This is an active multiplication of cells and tissue repair (regeneration).

Fever

Typical pathological processes include elevated temperature and oxygen starvation. You can start with a fever. It is characterized by a persistent increase in body temperature due to changes in the thermoregulation system. Evolutionally this reaction was formed to protect the body from infectious agents that died under the influence of high temperature.

A couple of centuries ago, all the diseases, in the process of development of which the temperature was rising, was called "fever". This term is present and now in the name of some nosological units, but not universally.

The essence of this phenomenon lies in the fact that the organism after it enters the pathogen produces specific substances - pyrogens. These chemical compounds affect the center of thermoregulation and shift the set point of the temperature constant higher than usual. But the thermoregulation mechanisms themselves retain their functions. This is the fundamental difference between fever and hyperthermia, during which the compensatory mechanisms of thermoregulation fail.

Hypoxia

Hypoxia is a typical pathological process that occurs due to a lack of oxygen in the air or due to a violation of its delivery to organs and tissues.

Distinguish:

Hypoxic hypoxia (reduction of oxygen pressure in the ambient air);
- respiratory or respiratory (violation of oxygen transport through the hematoalveolar barrier);
- gemic, otherwise blood (lowering blood capacity for oxygen molecules);
- circulatory (a decrease in the intensity of circulation);
- tissue (decrease in the perception of oxygen by tissues);
- reloading (membranes of organ cells are functionally overloaded);
- mixed;
- man-caused (develops if the body is in a medium with a high content of smog for a long time).

The most sensitive to lack of oxygen are nervous tissue, heart muscle, liver and kidney cells. To correct hypoxia, drugs that increase oxygen delivery to tissues or reduce the body's need for this gas are used.

Allergy

The concept of typical pathological processes can not do without mentioning allergies. This is a hypersensitive reaction of the body's immune system to the appearance of antigens in the body. There are four types of hypersensitivity:

1. Anaphylactic. During the first contact of the body with the antigen, a lot of immunoglobulin E is formed, which is attached to the mast cells and circulates in the blood. When repeated contact with the antigen, mast cells are destroyed, inflammatory mediators enter the blood and tissues , which cause a systemic reaction.
2. Cytotoxic. The antigen located on the cell membrane is captured by immunoglobulins of classes M and G. After that, the cell is destroyed by phagocytosis, either under the influence of complement proteins, or by natural killers.
3. Immunocomplex. Antibodies bind firmly to antigens and attach to the walls of the vessels. Vascular endothelial cells are destroyed by the release of enzymes.
4. Hypersensitivity of delayed type (HRT). Antigen, getting into the body, interacts with macrophages and T-helpers, stimulating immunity.

Stress

Stress is a collective concept that includes nonspecific adaptive mechanisms of the body, which are included under the influence of various external and internal factors. There are positive stress - eustress, and negative - distress. According to the type of exposure, the neuro-psychic, temperature, light, hunger and other stresses are distinguished.

Physiological stress is also called the general adaptation syndrome (OSA). Physiologist Hans Salie discovered that, in addition to compensating for the stressful state, damage to certain elements of the body is also observed: a decrease in the thymus gland, an increase in the adrenal cortex, and ulcers of the gastrointestinal tract.

The same scientist singled out three stages of the OAS:

- Anxiety (mobilization of body reserves);
- resistance;
- exhaustion.

Five years after the publication of his theory, in 1938, Salier proposed a theory of short-term and long-term adaptation.

Thrombosis

Typical pathological processes associated with circulatory disorders are hypoxia and thrombosis. The latter is the formation of convolutions of blood inside the vessels during human life. After damage to the artery, vein, capillary, or any other vessel, thrombocytes rush to the site of the rupture, which are fused together to form a primary thrombus. It covers the defect and stops the loss of blood from the vascular bed.

This is the positive side of the process. But under certain conditions (massive blood loss, disruption of adaptation mechanisms, increased lipid content), thrombi can form without damage to the bloodstream. Clots circulate through the bloodstream and can clog small (or large) vessels, causing ischemia and necrosis of the organ.

There are three factors that contribute to the development of thrombosis, so-called. Triad of Virchow:

- Hypercoagulation, or thrombophilia (the condition is caused by genetic defects or increased immunity readiness);
- damage to the cells of the mucous vessels (trauma, surgery, infection);
- violation of blood flow at the site of injury (blood stasis due to cardiovascular failure).

Tumor

Medical science allows us to treat a tumor as a typical pathological process. Definition of this concept sounds like this: it is a tissue that was formed as a result of a change in the genetic apparatus of the cell. These changes led to a disruption in their growth and differentiation.

All tumors are divided into two large groups: benign and malignant. There are five features inherent in all tumors:

- atypism (tissue or cellular);
- Organic structure;
- progression;
- autonomy;
- unlimited growth.

For benign, slow growth is characteristic. They do not form metastases and do not have a negative effect on the body as a whole. But with a combination of unfavorable circumstances, the tumor can be malignant.

Atrophy

Typical pathological processes include atrophy and dystrophy. Atrophy is a decrease in the size of organs and tissues due to a nutritional disorder. During atrophy, the thickness of muscle fibers decreases, the amount of actin and myosin, plastic substances decreases. In the myocardium there are areas of necrosis, and ulcers on the stomach mucosa. Atrophy develops at a time when a person is exhausted by a long illness or is forced to comply with strict bed rest, for example after a fracture or a heart attack.

The consequences of atrophy can be easily corrected if the motor activity is restored in a timely manner. Therefore, in surgery, it is customary to raise a patient in the postoperative period, in intensive care - to engage in physiotherapy and respiratory gymnastics.

In the non-medical sense, this word is used when they want to focus on the loss of any feeling or ability.

Dystrophy

Dystrophy is a typical pathological process, characterized by a disruption in the metabolism at the tissue level, which leads to their structural changes. At the heart of this process is the disruption of cell nutrition. Mechanisms of trophism of tissues and organs are divided into intracellular and extracellular.

Intracellular mechanisms include:

- transport of metabolic products through blood and lymph;
- intercellular mesenchyme;
- Neuroendocrine regulation.

Violation of each link individually or all together causes this or that kind of dystrophy. Isolate protein, fat, carbohydrate and mineral dystrophy, as well as chronic.

Atherosclerosis

Violation of lipid metabolism is also included in the typical pathological processes. Pathophysiology of this condition is associated with a violation of the exchange of fats and their deposition in the walls of the vessels. Lipids of low and very low density impregnate endothelial cells, forming atheromatous plaques. At the next stage, connective tissue grows in their place, which is imbibrated by calcium ions. The walls of the vessel are deformed, narrowed and can be completely clogged. This leads to ischemia and impaired function of the organ.