Hyalinosis

At hyalinosis(from the Greek. hyalos- transparent, glassy), or hyaline dystrophy, in the connective tissue, homogeneous translucent dense masses (hyaline) are formed, resembling hyaline cartilage. The tissue becomes denser, therefore, hyalinosis is considered as a type of sclerosis.

Hyalin is a fibrillar protein. In an immunohistochemical study, it detects not only plasma proteins, fibrin, but also components of immune complexes (immunoglobulins, complement fractions), as well as lipids. Hyaline masses are resistant to acids, alkalis, enzymes, PIC-positive, accept acidic dyes (eosin, acid fuchsin) well, and turn yellow or red with picrofuchsin.

Mechanism hyalinosis is complicated. Leading in its development are the destruction of fibrous structures and an increase in tissue-vascular permeability (plasmorrhage) in connection with angioneurotic (discirculatory), metabolic and immunopathological processes. Plasmorrhage is associated with tissue impregnation with plasma proteins and their adsorption on altered fibrous structures, followed by precipitation and the formation of a protein - hyaline. Smooth muscle cells are involved in the formation of vascular hyaline. Hyalinosis can develop as a result of various processes: plasma impregnation, fibrinoid swelling (fibrinoid), inflammation, necrosis, sclerosis.

Classification. Distinguish between vascular hyalinosis and hyalinosis of the connective tissue itself. Each of them can be widespread (systemic) and local.

Vascular hyalinosis. Small arteries and arterioles are mainly affected by hyalinosis. It is preceded by damage to the endothelium, its membrane and smooth muscle cells of the wall and its impregnation with blood plasma.

Hyalin is found in the subendothelial space, it pushes outwards and destroys the elastic plate, the middle membrane becomes thinner, in the final arterioles turn into thickened vitreous tubes with a sharply narrowed or completely closed lumen

Spleen vascular hyalinosis:

a - the wall of the central artery of the spleen follicle is represented by homogeneous masses of hyaline; b - fibrin among hyaline masses when stained by the Weigert method; c - fixation of IgG immune complexes in hyaline (luminescence microscopy); d - mass of hyaline (G) in the arteriole wall; En - endothelium; Pr - the lumen of the arteriole. Electronogram.

Hyalinosis of small arteries and arterioles is systemic, but most pronounced in the kidneys, brain, retina, pancreas, and skin. It is especially characteristic of hypertension and hypertensive states (hypertensive arteriologialinosis), diabetic microangiopathy (diabetic arteriologialinosis) and diseases with impaired immunity. As a physiological phenomenon, local arterial hyalinosis is observed in the spleen of adults and the elderly, reflecting the functional and morphological features of the spleen as an organ of blood deposition.

Vascular hyaline is a substance of predominantly hematogenous nature. In its formation, not only hemodynamic and metabolic, but also immune mechanisms play a role. Guided by the peculiarities of the pathogenesis of vascular hyalinosis, there are 3 types of vascular hyaline:

1) simple, arising as a result of the insudation of unchanged or slightly changed components of blood plasma (occurs more often in hypertension of a benign course, atherosclerosis and in healthy people);

2) lipogyalin, containing lipids and β-lipoproteins (found most often in diabetes mellitus);

3) complex hyaline, built from immune complexes, fibrin and collapsing structures of the vascular wall (typical for diseases with immunopathological disorders, for example, for rheumatic diseases).

Hyalinosis of the connective tissue itself. It usually develops as a result of fibrinoid swelling, leading to the destruction of collagen and saturation of the tissue with plasma proteins and polysaccharides.

Microscopic examination. They find swelling of the connective tissue bundles, they lose fibrillarity and merge into a homogeneous dense cartilage-like mass; cellular elements are compressed and atrophy. This mechanism of development of systemic hyalinosis of the connective tissue is especially common in diseases with immune disorders (rheumatic diseases). Hyalinosis can complete fibrinoid changes in the bottom of a chronic stomach ulcer, in the appendix with appendicitis; it is similar to the mechanism of local hyalinosis in the focus of chronic inflammation.

Hyalinosis as an outcome of sclerosis is also mainly local in nature: it develops in scars, fibrous adhesions of serous cavities, the vascular wall in atherosclerosis, involutional sclerosis of the arteries, when organizing a thrombus, in capsules, tumor stroma, etc. In these cases, hyalinosis is based on disorders in the exchange of connective tissue. A similar mechanism has hyalinosis of necrotic tissues and fibrinous overlays.

Appearance. With severe hyalinosis, the appearance of the organs changes. Hyalinosis of small arteries and arterioles leads to atrophy, deformation and wrinkling of the organ (for example, the development of arteriolosclerotic nephrocirrhosis).

With hyalinosis of the connective tissue itself, it becomes dense, whitish, translucent (for example, hyalinosis of the heart valves in rheumatic disease).

Exodus. In most cases, it is unfavorable, but resorption of hyaline masses is also possible. So, hyaline in scars - the so-called keloids - can undergo loosening and resorption. Let us reverse the hyalinosis of the mammary gland, and the resorption of the hyaline masses occurs under conditions of hyperfunction of the glands. Sometimes the hyalinized tissue becomes mucous.

Functional value. It differs depending on the location, degree and prevalence of hyalinosis. Widespread hyalinosis of arterioles can lead to functional organ failure (renal failure in arteriolosclerotic nephrocirrhosis). Local hyalinosis (for example, heart valves in case of heart disease) can also be the cause of functional organ failure. But in scars, it may not cause much disturbance.

Topic 2. Stromal-vascular dystrophies

2.1. Stromal-vascular protein dystrophies (dysproteinosis)

2.1.3. Hyalinosis

At hyalinosis (from the Greek. hyalos- transparent, glassy), or hyaline dystrophy, in the connective tissue, homogeneous translucent dense masses (hyaline) are formed, resembling hyaline cartilage.

Hyalin is a fibrillar protein. In an immunohistochemical study, it detects not only plasma proteins, fibrin, but also components of immune complexes (immunoglobulins, complement fractions), and sometimes lipids. Hyaline masses are resistant to acids, alkalis, enzymes, PIC-positive, accept acidic dyes (eosin, acid fuchsin) well, and turn yellow or red with picrofuchsin.

Hyalinosis can develop at the end different processes:

-plasma impregnation;
-fibrinoid swelling (fibrinoid);
- sclerosis.

Classification. Distinguish:

-vascular hyalinosis;
-hyalinosis of the connective tissue itself.

Each of the two types of hyalinosis can be worn systemic and local character.

Vascular hyalinosis... Small arteries and arterioles are mainly affected by hyalinosis. It is preceded by damage to the endothelium, basement membrane and smooth muscle cells of the vessel wall and its impregnation with blood plasma proteins.

Causes systemic vascular hyalinosis:

-hypertonic disease;
-hypertensive conditions, hypertension (kidney disease, tumors of the endocrine and gonads);
-diabetes (diabetic arteriologialinosis);
-rheumatic diseases;
-atherosclerosis.

The leading mechanisms in its development are:

-destruction of fibrous structures;
-increased vascular tissue permeability (plasmorrhage).

Plasmorrhage is associated with tissue impregnation with plasma proteins and their adsorption on altered fibrous structures, followed by precipitation and the formation of a protein - hyaline.

Hyalinosis of small arteries and arterioles is systemic, but most pronounced in the kidneys, brain, retina, pancreas, and skin.

Microscopically, with hyalinosis, arterioles turn into thickened vitreous tubes with a sharply narrowed or completely closed lumen.

Guided by the peculiarities of the pathogenesis of vascular hyalinosis, there are 3 types of vascular hyaline:

1) simple , arising from little changed components of blood plasma (occurs more often in hypertension of a benign course, atherosclerosis and in healthy people);

2) lipogyalin , containing lipids and beta-lipoproteins (found most often in diabetes mellitus);

3) complex hyaline , built from immune complexes, fibrin and collapsing structures of the vascular wall (typical for diseases with immunopathological disorders, for example, for rheumatic diseases).

Local hyalinosis of the arteries as a physiological phenomenon is observed in the spleen of adults and the elderly, reflecting the functional and morphological features of the spleen as an organ of blood deposition.

Exodus. In most cases, it is unfavorable, since the process is irreversible. Hyalinosis of small arteries and arterioles leads to atrophy, deformation and wrinkling of the organ (for example, the development of arteriolosclerotic nephrocirrhosis).

Meaning. It differs depending on the location, degree and prevalence of hyalinosis. Widespread hyalinosis of arterioles can lead to functional organ failure (renal failure in arteriolosclerotic nephrocirrhosis). Vascular fragility leads to the development of hemorrhages (for example, hemorrhagic stroke in hypertension).

Hyalinosis of the connective tissue proper.

Systemic hyalinosis of connective tissue and blood vessels usually develops as a result of fibrinoid swelling, leading to the destruction of collagen and saturation of the tissue with plasma proteins and polysaccharides. This mechanism of development of systemic hyalinosis of the connective tissue is especially common in diseases with immune disorders (rheumatic diseases).

Local hyalinosis as an outcome of sclerosis develops in scars, fibrous adhesions of serous cavities, vascular wall in atherosclerosis, involutional sclerosis of the arteries, in the organization of a thrombus, heart attack, healing of ulcers, wounds, in capsules, tumor stroma, etc. In these cases, hyalinosis is based on disorders in the exchange of connective tissue. A similar mechanism has hyalinosis of necrotic tissues and fibrinous overlays in the pleura, pericardium, etc. Hyalinosis can complete fibrinoid changes in the bottom of a chronic stomach ulcer, in the appendix with appendicitis.

Microscopic examination. Bundles of collagen fibers lose their fibrillation and merge into a homogeneous dense cartilage-like mass; cellular elements are compressed and atrophy.

Macroscopic picture. With pronounced hyalinosis, the fibrous connective tissue becomes dense, cartilaginous, whitish, translucent.

Exodus... In most cases, it is unfavorable due to the irreversibility of the process, but resorption of hyaline masses is also possible. So, hyaline in scars - the so-called keloids - can undergo loosening and resorption. Let us reverse the hyalinosis of the mammary gland, and the resorption of the hyaline masses occurs under conditions of hyperfunction of the glands. Sometimes the hyalinized tissue becomes mucous.

Meaning... It differs depending on the location, degree and prevalence of hyalinosis. Local hyalinosis can be the cause of functional organ failure. In scars, it may not cause any particular disturbance, with the exception of a cosmetic defect.

Previous

Mechanisms of cell damage and death 1. Formation of free radicals (with insufficient supply of oxygen to the tissues), free radical lipid peroxidation (SPOL) occurs. 2. Violation of calcium homeostasis. Free calcium in the cytoplasm of cells is contained in very low concentrations in comparison with extracellular calcium. This state is maintained by Ca2 +, Mg2 + -ATPases. Ischemia, intoxication cause an increase in the concentration of calcium in the cytoplasm, which leads to the activation of enzymes that damage the cell: phospholipases (damage to the cell membrane), proteases (destruction of the membrane and cytoskeleton proteins), ATPases (depletion of ATP stores) and endonucleases (chromatin fragmentation). 3. ATP deficiency leads to the loss of the integrity of the plasma membrane and, consequently, to cell death. 4. Early loss of selective permeability by the plasma membrane. It occurs with ATP deficiency, and with the activation of phospholipases. The plasma membrane can be damaged by direct exposure to bacterial toxins, viral proteins, complement, physical, chemical agents.

Forms of cell damage

Distinguish between: · Ischemic and hypoxic damage; · Damage caused by free radicals, including activated oxygen; · Toxic damage. Ischemic and hypoxic damage. More often due to arterial occlusion. The main mechanisms of cell death during hypoxia are a violation of oxidative phosphorylation, leading to ATP deficiency, damage to cell membranes. The most important mediator of irreversible biochemical and morphological changes is calcium. Cell damage caused by free radicals. It occurs under the influence of chemicals, radiation, oxygen, aging of cells, destruction of tumors by macrophages. Free radicals reacts with inorganic and organic compounds - proteins, lipids and carbohydrates. Three reactions in which free radicals enter are most important for cell damage. · Free radical lipid peroxidation (SPOL) of membranes, leading to damage to membranes, organelles and cells themselves. · Oxidative transformation of proteins. Free radicals cause cross-linking of amino acids (methionine, histidine, cystine, lysine). Destroys enzymes through neutral proteases. · DNA damage. Free radicals react with thymine, which is a part of DNA, this leads to cell death or its malignant transformation. · Toxic damage. Chemicals (in the form of water-soluble compounds) can act directly by binding to molecules or organelles in the cell. For example, mercury binds sulfhydryl groups of the cell membrane and causes an increase in the permeability of the cell membrane and inhibition of ATPase-dependent transport. When mercury chloride enters the body, the cells of the gastrointestinal tract and kidneys are most affected. Cyanide acts on mitochondrial enzymes. Antineoplastic chemotherapy drugs (including antibiotics) cause cell damage through a cytotoxic effect. Chemical compounds (fat-soluble) are first converted into toxic metabolites, which then act on target cells. This creates free radicals.

In classical morphology, non-lethal cell damage is called dystrophy.

8. Death of the cell. Apoptosis. Definition of the concept. Morphological manifestations of apoptosis and the mechanism of their development. Physiological and pathological significance of apoptosis.

Cell death is irreversible damage to the cell

Apoptosis-genitically programmed cell death in a living organism. To remove (emilate) unnecessary cell structures in the process of embryogenesis.

Morphological manifestations:

1-condensation of nuclear heterochromatin and shrinkage of cells with preservation of the integrity of organelles and cell membranes.

2- cell decay into apoptosis bodies, which are membrane structures with a conclusion and inside organelles and particles of the nucleus

3- then apoptotic bodies are phagocytosed and destroyed with the help of lysosomes of the surroundings and cells.

Mechanism:

1-Chromatin condensation is associated with the cleavage of nuclear DNA, CT occurs in the sites of bonds between nucleosomes and leads to the formation of fragments.

2- Violation of cell volume and size is explained by the activity of transglutaminase. This fer-t catalysis is the cross-binding of cytoplasm proteins, the image is a shell under the plasma membrane.

3-Phagositosis of apoptotic bodies by macrophages and other cells.

4. The dependence of apoptosis on gene activation is one of its important features. This is provided by protooncogenes. Apoptosis-specific genes have been identified that stimulate or inhibit cell death. 5. Oncogenes and suppressor genes play a regulatory role in the induction of apoptosis (the p53 oncogene normally stimulates apoptosis; p53 is necessary for the development of apoptosis after DNA damage by radiation).

Physiological and pathological significance of apoptosis:

1-mediates the programmed removal of cells during embryogenesis (including implantation, organogenesis and involution)

2- hormone-dependent involution of cells occurs in adults

3-ensures the destruction of cells in proliferating cell populations, such as the epithelium of the crypts of the small intestine and cell death in tumors

4- h / h apoptosis, death of autoreactive clones of T-ltmphocytes and pathological atrophy of hormone-dependent mc are realized

5- apoptosis underlies the pathological atrophy of parenchymal organs after the closure of the duct

6- cell death caused by cytotoxic and T-cells and cell death in nect viral diseases are associated with apoptosis

7-apoptosis underlies cell death caused by various and weak damaging effects, and high doses of CT lead to cell death (the term is ubiquitous, radiation, cytotoxic anticancer drugs and, possibly, hypoxia)

9. Necrosis. Definition of the concept. Macroscopic and microscopic signs of necrosis.

Necrosis - Death, death of cells and mk in a living organism; at the same time, they completely stop living. It is a spectrum of morophological changes that develop after the death of cells in a living tissue. This is the result of the destruction of the action of enzymes on the lethally damaged cell. In fact, two jumping processes develop: enzyme digestion and protein denaturation.

Morphogenesis of necrosis:

1-paranecrosis-like necrotic, but reversible betrayal.

2-necrobiosis-irreversible dystrophic change, characterized by the predominance of catabolic reactions over anabolic

3-death kt, the time of the onset of kt is difficult to get tired

4-autolysis-decomposition of dead substrate under the influence of hydrolytic fer of dead cells and macrophages.

Macro: signs of necrosis can manifest themselves in different ways: they depend on the originality of the organ in which necrosis occurs, as well as on the nature of the damaging factor.

Micro: signs relate to both the nucleus and the cytoplasm of the cell, as well as the extracellular matrix.

Kernel change on:

Karyopyknosis - shrinking of nuclei due to chromatin condensation;

Karyorexis - decay of nuclei into lumps

Karyolysis - dissolution of the nucleus due to the activation of hydrolases (RNase and DNase)

Change cit:

Plasma coagulation - protein denaturation and coagulation with the appearance of bright pink lumps in the cytoplasm

Plasmorhexis-disintegration of the cytoplasm into lumps

Plasmolysis - melting of the cytoplasm

Change the extra-on of the development matrix:

In the splitting of reticular, collagen and elastic fibers under the influence of proteases, elastases, collagenases. Necrotic masses are often impregnated with fibrin with the development of fibrinoid necrosis.

Details

Mesenchymal dystrophies develop as a result of metabolic disorders in the connective tissue and are detected in the structure of organs and vascular walls. With metabolic disorders in connective tissue, mainly in its intercellular substance, metabolic products accumulate, which can be brought in with blood and lymph, be the result of perverted synthesis, or appear as a result of disorganization of the basic substance and fibers of connective tissue.

1. Stromal-vascular dysproteinosis

Dystrophies of this type include mucoid swelling, fibrinoid swelling, hyalinosis, amyloidosis.

Often, mucoid swelling, fibrinoid swelling and hyalinosis are successive stages in the disorganization of connective tissue. This process is based on the accumulation of blood plasma products in the main substance as a result of an increase in tissue-vascular permeability ( plasmorrhage), destruction of connective tissue elements and the formation of protein-polysaccharide complexes. Amyloidosis differs in that the composition of the complex formed includes an abnormal protein that amyloidoblasts synthesize.

1) Mucoid swelling

Superficial and reversible disorganization of connective tissue. In this case, the accumulation and redistribution of glycosaminoglycans occurs in the main substance due to an increase in the content of primarily glucuronic acid. Since glycosaminoglycans have increased hydrophilic properties, their accumulation leads to an increase in tissue and vascular permeability. As a result, plasma proteins (mainly globulins) and glycoproteins are mixed with GAGs. Hydration and swelling of the main interstitial substance develop.

Microscopy: the main substance is basophilic. A phenomenon arises metachromasia- a change in the state of the main intermediate substance due to a change in pH with the accumulation of chromotropic substances. Collagen fibers swell and usually retain their bundle structure. They become unstable to the action of collagenase.

Changes may be accompanied by the appearance of lymphocytic, plasma cell and histiocytic infiltrates.

This type of swelling is found in various organs and tissues, but more often in the walls of arteries, heart valves, endocardium, epicardium, that is, where chromotropic substances are found in normal conditions (however, with pathology, their number increases sharply).

Appearance: tissue or organ is preserved.

Causes: hypoxia, infectious and allergic diseases, rheumatic diseases, atherosclerosis, endocrinopathy, etc.

Exodus: twofold. Either complete tissue repair or transition to fibrinoid swelling.

2) Fibrinoid swelling.

Deep and irreversible disorganization of connective tissue, which is based on the destruction of its main substance and fibers, accompanied by a sharp increase in vascular permeability and the formation of fibrinoid. Fibrinoid- a complex substance, it contains proteins and polysaccharides of disintegrating collagen fibers, the main substance and blood plasma, as well as cellular nucleoproteins. Fibrin is an obligatory component.

Microscopy: bundles of collagen fibers, impregnated with plasma, become homogeneous, forming insoluble strong eosinophilic compounds with fibrin. Tissue metachromasia is not expressed or weakly expressed (since the GAGs of the main substance are depolymerized).

Appearance: Externally, organs and tissues change little.

Causes: most often this is a manifestation of infectious-allergic, autoimmune and angioedema reactions. In such cases, the swelling is systemic. Locally fibrinoid swelling can occur with inflammation, especially chronic inflammation.

Exodus: characterized by the development of fibrinoid necrosis, replacement of the destruction focus with connective tissue (sclerosis) or hyalinosis.

Such swelling leads to disruption, sometimes to the cessation of organ function.

3) Hyalinosis

In the connective tissue, homogeneous translucent dense masses are formed, resembling hyaline cartilage. At the same time, the fabric is denser.

Destruction of fibrous structures and an increase in tissue-vascular permeability play a leading role in the development of hyalinosis. Plasmorrhage is associated with tissue impregnation with plasma proteins and their adsorption on altered fibrous structures, followed by precipitation and the formation of hyaline. Smooth muscle cells are involved in the formation of vascular hyaline. Hyalinosis can develop as a result of various processes: plasma impregnation, fibrinoid swelling, inflammation.

Distinguish:

A) vascular hyalinosis

Small arteries and arterioles are mainly affected by hyalinosis. It is preceded by damage to the endothelium, its membrane and smooth muscle cells of the wall and its impregnation with blood plasma.

Microscopy: hyaline is found in the subendothelial space6 it pushes outwards and destroys the elastic plate, the middle membrane becomes thinner, in the phial the arterioles turn into thickened glass tubes with a sharply narrowed or completely closed lumen.

Such hyalinosis is of a systemic nature, however6 it is most pronounced in the kidneys, brain, retina, pancreas, and skin. It is characteristic of hypertension, diabetic microangiopathy and diseases with impaired immunity. As a physiological phenomenon, local arterial hyalinosis is observed in the spleen of adults and the elderly (reflects the functional and morphological features of this organ - blood deposition).

Vascular hyaline- a substance of predominantly hematogenous nature. Guided by the peculiarities of the pathogenesis of vascular hyalinosis, there are:

- simple vascular hyaline

It arises as a result of insudation of unchanged or slightly altered components of blood plasma.This type of hyaline is more common in patients with benign hypertension, atherosclerosis, as well as in healthy people.

- lipogyalin

Contains lipids and beta-lipoproteins. This type of hyaline is often found in diabetes mellitus.

- complex hyaline

It is built from immune complexes, fibrin and collapsing structures of the vascular wall. Such hyaline is typical for patients with immunopathologies, for example, with rheumatic diseases.

B) hyalinosis of the connective tissue itself

It develops, as a rule, as a result of fibrinoid swelling, leading to the destruction of collagen and saturation of the tissue with plasma proteins and polysaccharides.

Hyalinosis of the myometrium is of great clinical importance. After performing a Cesarean section, a scar remains on the uterus, and hyaline is deposited in the cells on the border with the muscle. If a woman gives birth to a second child naturally, then a rupture will occur.

Microscopy: connective tissue bundles lose fibrillarity, and cellular elements turn into a cartilage-like mass.

Hyalinosis can complete fibrinoid changes in the focus of chronic inflammation. Hyalinosis as an outcome of sclerosis is mainly local in nature: it develops in scars, fibrous adhesions of serous cavities, and the vascular wall in atherosclerosis.

Appearance: with severe hyalinosis, the appearance of the organs changes. Hyalinosis of arterioles and small arteries leads to atrophy, deformation and wrinkling of the organ. With hyalinosis of the connective tissue itself, it becomes dense, whitish, translucent.

Exodus: in most cases unfavorable, however, resorption of hyaline masses is also possible.

4) Amyloidosis

It is accompanied by a profound disturbance of protein metabolism, the appearance of an abnormal fibrillar protein and the formation of amyloid in the interstitial tissue and vascular walls.

Amyloid is a glycoprotein, the main component of which is fibrillar proteins (F-component, synthesized by amyloidoblasts). They form fibrils ... Fibrillar proteins amyloid heterogeneous:

a) AA protein: not associated with immunoglobulins, formed from its serum analogue - SAA protein

b) AL protein: associated with immunoglobulins, its precursor is immunoglobulin light chains

c) AF protein: prealbumin is involved in its formation

d) ASC 1 protein - a protein whose precursor is also prealbumin

These fibrillar proteins form complex compounds with blood plasma glucoproteins. This plasma component (P-component) of amyloid is represented by rod-shaped structures.

Both the F and P components are antigenic. The amyloid fibrils and the plasma component enter into compounds in the tissue chondroitin sulfates, and “hematogenous additives” are added to the resulting complex, among which fibrin and immune complexes are of primary importance. All bonds in amyloid are very strong, so the body's enzymes do not act on it.

Classification amyloidosis is based on possible causes, specificity of fibrillar proteins, prevalence, clinical manifestations.

A. For reasons of occurrence:

Primary (idiopathic) amyloidosis

It is characterized by: the absence of a previous or concomitant "causal" disease; damage to mainly mesodermal tissues - CVS, skeletal and smooth muscles, nerves and skin; tendency to form nodular deposits, inconsistency of the colorful reactions of the amyloid substance

Hereditary (genetic, familial) amyloidosis

Hereditary amyloidosis with predominant kidney damage is characteristic of periodic illness (familial Mediterranean fever), which is more often observed in representatives of ancient peoples (Jews, Armenians, Arabs).

Secondary (acquired) amyloidosis

Unlike other forms, it develops as a complication, and not as an independent disease. Chronic nonspecific inflammatory diseases of the lungs, tuberculosis, osteomyelitis, malignant neoplasms, and rheumatic diseases lead to such amyloidosis.

Such amyloidosis, as a rule, is generalized and occurs most often.

Senile amyloidosis

Typical lesions of the heart, arteries, brain, islets of Langerhans. These changes lead to physical and mental aging degradation. In senile amyloidosis, local forms are most common, although generalized senile amyloidosis is also encountered.

B. By the specificity of fibrillar proteins:

AL amyloidosis

Includes primary (idiopathic) amyloidosis and amyloidosis with "plasma cell dyscrasia", which combines paraproteinemic leukemias, malignant lymphomas, etc.

Always generalized with damage to the heart, lungs and blood vessels.

AA amyloidosis

Covers secondary amyloidosis and McCle and Wales diseases. It is also generalized, but predominantly affects the kidneys.

AF amyloidosis

Hereditary, represented by familial amyloid nephropathy. The peripheral nerves are mainly affected.

ASC 1 - amyloidosis

Senile generalized or systemic with predominant damage to the heart and blood vessels.

B. By prevalence

- generalized form

Primary amyloidosis, amyloidosis with “plasma cell dyscrasia” (AL), secondary amyloidosis and some types of hereditary (AA), senile systemic amyloidosis (ASC 1).

Local amyloidosis

It combines a number of forms of hereditary and senile amyloidosis, as well as local tumor-like amyloidosis.

D. According to clinical manifestations

- cardiopathic

More common in primary and senile systemic amyloidosis.

- nephropathic

With secondary amyloidosis, periodic illness and McCle and Wells disease.

- neuropathic

As a rule, it is hereditary.

Hepatopathic

Epinephropathic

- mixed

Secondary amyloidosis.

APUD amyloidosis

It develops in the organs of the APUD system during the development of tumors (apudomas) in them, as well as in the islets of the pancreas with senile amyloidosis.

Morpho- and pathogenesis of amyloidosis

Sometimes the function of amyloidoblasts is performed by macrophages, plasma cells, fibroblasts, etc. In local forms, cardiomyocytes, smooth muscle cells, keratinocytes can act as amyloidoblasts.

In secondary amyloidosis (excluding amyloidosis in "plasma cell dyscrasia") mutations and the appearance of amyloidoblasts can be associated with prolonged antigenic stimulation.

Cell mutations in "plasma cell dyscrasia" and in tumor amyloidosis are caused by tumor mutagens.

In genetic amyloidosis, we are talking about a gene mutation that can occur at different loci, which is the difference in the composition of amyloid proteins. Probably, similar mechanisms take place in senile amyloidosis.

Since the antigens of the amyloid fibril protein are extremely weak immunogens, mutating cells are not recognized or eliminated. Immunological tolerance to amyloid proteins develops, which leads to the progression of amyloidosis.

The formation of amyloid protein may be associated with:

Reticular fibers (perireticular amyloidosis)

Amyloid falls out along the membranes of blood vessels and glands, as well as the reticular stroma of the parenchymal organs. Characterized by a predominant lesion of the spleen, liver, kidneys, adrenal glands, intestines, intima of small and medium-sized vessels (parenchymal amyloidosis).

Collagen fibers (pericollagen)

Amyloid falls out along the collagen fibers, mainly affecting the adventitia of medium and large vessels, myocardium, striated and smooth muscles, nerves, skin (mesenchymal amyloidosis).

Pathogenesis amyloidosis is complex and ambiguous. The pathogenesis of AA and AL amyloidosis is best studied.

At AA amyloidosis amyloid fibrils are formed from the precursor of the fibrillar amyloid protein entering the macrophage - the SAA protein, which is synthesized in the liver. SAA synthesis stimulates the macrophage mediator interleukin-1, which leads to a sharp increase in SAA in the blood. Under these conditions, macrophages do not completely degrade SAA, and amyloid fibrils are assembled from its fragments and invaginates of the plasma membrane of amyloidoblast. This assembly is stimulated by the amyloid-stimulating factor - ASF, which is found in tissues in the preamyloid stage.

So, the magrophage system plays a leading role in the pathogenesis of AA amyloidosis: it stimulates the enhanced synthesis of SAA, it also participates in the formation of amyloid fibrils from degrading protein fragments.

At AL amyloidosis the serum precursor of amyloid fibril protein are immunoglobulin L-chains. There are two possible mechanisms for the formation of AL fibrils: 1) violation of the degradation of light chains with the formation of fragments capable of aggregation of a fibril; 2) the appearance of light chains with special secondary and tertiary structures during amino acid substitutions.

The synthesis of amyloid fibrils can occur not only in macrophages, but also in plasma and myeloma cells that synthesize paraproteins.

Accordingly, the appearance of amyloidogenic light chains of immunoglobulins, a precursor of amyloid fibrils, is associated with the perverted function of the lymphoid system.

Macro and microscopy

The appearance of the organs depends on the degree of the process. If the deposits are small, the appearance of the organ is little changed. With severe amyloidosis, the organ enlarges, becomes very dense and brittle, and on the cut it has a waxy, greasy appearance.

V spleen amyloid is deposited in the lymphatic follicles (the sago spleen is dense, enlarged, translucent grains on the cut) or evenly throughout the pulp (the sebaceous spleen is enlarged, dense, brown-red, smooth, has a greasy sheen on the cut).

V kidneys amyloid is deposited in the vascular wall, in the capillary loops and mesangia of the glomeruli, in the basement membranes of the tubules and in the stroma. The kidneys become dense, large, greasy. As the process grows, the glomeruli and pyramids are completely replaced by amyloid, connective tissue grows and amyloid wrinkling develops.

V liver deposition of amyloid is observed along the reticular stroma of the lobules. In the walls of blood vessels, ducts, connective tissue of the portal tracts. Hepatocytes shrink and die. The liver is enlarged, dense, looks greasy.

V intestines amyloid falls out along the reticular stroma of the mucous membrane, as well as in the vessel walls of both the mucous membrane and the submucosa. With pronounced amyloidosis, the glandular apparatus of the intestine atrophies.

V heart amyloid is found under the endocardium, in the stroma and vessels of the myocardium, as well as in the epicardium along the veins. Deposition leads to amyloid cardiomegaly. The heart becomes dense, greasy.

Exodus amyloidosis is unfavorable.

2. Stromal-vascular lipidoses

They occur when there are disorders in the metabolism of neutral fats or cholesterol and its esters.

Neutral fats- labile fats that provide the body's energy supply.

Obesity- an increase in the amount of neutral fats in fat depots, which is of a general nature. It is expressed in the abundant deposition of fat in the subcutaneous tissue, omentum, mesentery. mediastinum, epicardium. Adipose tissue also appears where it is normally absent, for example, in the stroma of the myocardium, pancreas.

Classification is based on different principles:

A. On the etiological basis:

Primary form

Its cause is unknown, which is why it is called idiopathic.

Secondary form

Represented by the following types:

Alimentary, the cause of which is physical inactivity and unbalanced nutrition

Cerebral, developing with trauma, tumors, a number of neurotropic infections

Endocrine-syndromes Itsenko-Cushing, Frohlich

Hereditary - Lawrence-Moon-Biedl syndrome, Gierke's disease

B. By external manifestations:

Symmetric type

Fats are deposited evenly in different parts of the body.

Accumulation in the subcutaneous tissue of the face, occiput, neck, upper shoulder girdle, mammary glands.

Fat is deposited in the subcutaneous tissue of the abdomen in the form of an apron

In the area of ​​the thighs and legs

B. Overweight:

I degree - 20-29% overweight

II degree - 30-49%

III degree - 50-99%

IV degree - 100% or more

D. According to the characteristics of morphological changes

The number of adipocytes and their size are taken into account.

Hypertrophic type

Fat cells are enlarged and contain several times more triglycerides than normal ones. The number of adipocytes does not change. Adipocytes are insensitive to insulin, but highly sensitive to lipolytic hormones.

Hyperplastic type

The number of adipocytes increases. The function of adipocytes is not impaired, there are no metabolic changes, the course of the disease is benign.

Causes and mechanisms of development

Unbalanced nutrition, physical inactivity, violation of the central nervous system, endocrine regulation, hereditary factors are of great importance.

The direct mechanism of obesity lies in the imbalance of lipogenesis and lipolysis in the fat cell in favor of lipogenesis.

Exodus: seldom favorable.

Disorders of the metabolism of cholesterol and its esters.

Such disorders underlie atherosclerosis. At the same time, cholesterol and its esters accumulate in the intima of the arteries, but also low-density beta-lipoproteins and blood plasma proteins, which is facilitated by an increase in vascular permeability.

The accumulation leads to the destruction of the intima.

As a result, fatty protein detritus forms in the intima, connective tissue grows, and a fibrous plaque forms, narrowing the lumen of the vessel.

3. Stromal-vascular carbohydrate dystrophies

May be associated with an imbalance of glycoproteins and glycosaminoglycans.

Slime tissue- dystrophy associated with impaired glycoprotein metabolism. Chromotropic substances are released from the bonds with proteins and accumulate in the intermediate substance. In contrast to mucoid swelling, collagen fibers are replaced by a mucoid mass. Connective tissue, organ stroma, adipose tissue, cartilage become translucent, mucoid, and their cells become stellate.

Cause: most often due to dysfunction of endocrine jellies, exhaustion (for example, myxedema, mucous edema, mucous connective tissues with cachexia).

Exodus: The process may be reversible, but its progression leads to colliquation and necrosis.

Hyalinosis is a proteinaceous extracellular dystrophy, which is characterized by the formation of homogeneous, translucent, dense masses that resemble hyaline cartilage. This pathological process can manifest itself as an independent disease, or it can proceed with the main ailment and be one of the symptoms of its severe course.

Dystrophy can spread and invade most tissues and organs of the human body. The disease occurs quite often in adults, regardless of gender. The reasons for the appearance are of a different nature of origin.

The disease is diagnosed after a comprehensive study, and with a severe course of the disease, the prognosis is poor.

Etiology

This pathological process is a collective concept that combines various biological processes.

The main causes of pathological processes in tissues or organs are:

• systemic diseases (diabetes, vascular disease, heart, joints);
• protein metabolism disorders.

Pathology can manifest itself in a local form, or it can affect the whole system.

Hyalinosis of the spleen capsule, like other forms, causes destruction of the fibrous structures of connective tissues, and also leads to changes:

• in metabolism;
• in the immune system;
• the impermeability of tissues is disturbed;
• causes the accumulation of proteins;
• leads to an increase in the fibrous structure of tissues.

In the process of dystrophy, a hyaline-fibrillar protein is formed, which accumulates in tissues and is stable:

• to the effects of alkalis;
• does not lend itself to oxidation;
• it is not affected by enzymes.

However, under the influence of eosin and fuchsin, it changes color to yellow or red.

The disease can be asymptomatic and not manifest in any way, but it can have a severe course and cause various disorders in the tissues or organs where it is localized. Excessive formation of hyaline causes compaction, pallor, and can lead to deformational changes and wrinkling of organs.

Classification

Pathology has two forms of existence in connective tissue and blood vessels, it can have both local (focal) and systemic character. The local character includes hyalinosis of the heart valves, which contributes to an increase in the organ, expands the ventricles, the mitral valve becomes dense, with a whitish tint, and is deformed.

There are three types of vascular hyalinosis:

• simple - it is formed due to the release of plasma from its bed due to the expansion and decrease in the density of the vascular walls, often this picture is observed with and;
• lipogyalin - its structure contains lipids and beta-lipoproteins, occurs when;
• complex - consists of immune complexes, fibrin and decaying components, occurs in rheumatic immunological diseases.

The pathological process in the vessels develops due to an increase in blood pressure and a decrease in vascular permeability or with prolonged vasospasm.

The pathology of the connective tissue occurs after its damage and disorganization under the influence of immune complexes. It manifests itself in rheumatic lesions of the valves of the heart valves, their patency, mobility decreases, they become denser. The accumulation of a homogeneous substance causes an increase in the distance between cells.

Stromal hyalinosis is quite common. The stroma consists of connective tissue, which performs the supporting function of the supporting structures of the organ, and if it is damaged, the functional abilities and work of the organ are impaired.

The pathological process of the serous membranes is one of the options for the outcome of fibrous inflammation, which is characteristic of,. In this case, fibrin is deposited on the membrane. Most often, hyalinosis of the spleen capsule is observed, which manifests itself locally, causes a milky-white thickening of the capsule: it seems to be covered with glaze. The same picture is observed in the liver, heart, lungs. The distance between the shell increases due to the accumulation of matter.

Symptoms

The signs of the disease will directly depend on the organ or tissues in which pathological processes are observed:

• vascular hyalinosis - permeability and elasticity are disturbed, bleeding, frequent headaches and inflammation are possible, vascular permeability can be disrupted, which reduces the supply of oxygen and nutrients to organs and tissues;
• hyalinosis of the pleura - causes a chronic process of pulmonary adhesions due to a violation of protein metabolism or as a result of a tuberculous disease, in this case pulmonary ventilation is limited, but when the process is mild, the course of the disease does not manifest itself in any way;
• protein dystrophy in organs - causes their deformation and wrinkling, contributes to the onset of pain, hardening, partial loss of functionality, nutrition worsens and the supply of nutrients and oxygen is disrupted;
• pathology of the mammary gland - causes compaction and heaviness in the chest, it can dissolve itself and not cause any complications due to disruptions in protein formation;
• hyalinosis in myoma - observed in inflammatory processes or tumor-like formations, can manifest itself as painful sensations, discharge from the genitals.

Local hyalinosis is susceptible to therapeutic measures, while systemic hyalinosis has adverse consequences.

When hyalinosis of the spleen capsule appears, its functionality is most often disrupted, which leads to dire consequences: blood flow and metabolism are disturbed, and infected blood cells are filtered.

In this case, a person experiences severe ailments, pain, bleeding occurs, and immunity worsens.

Diagnostics

The diagnosis is made only after a comprehensive examination.

The patient is referred for the following examinations:

• a general and biochemical blood test is taken;
• urine is examined;
• an ultrasound examination of blood vessels, internal organs or tissues is prescribed;
• magnetic resonance imaging may be prescribed;
• smears are taken and an ultrasound of the female genital organs is performed;
• X-ray studies of the lungs.

Macrodrug may have adhesions, seals, whitish enveloping of the organ is observed. After research, the cause and type of the disease is established, and depending on the diagnosis, treatment will be prescribed.

Treatment

After establishing the main diagnosis, the doctor determines the tactics of therapeutic measures. First of all, the main pathological process is eliminated.

Funds may be prescribed to improve performance:

• spleen;
• hearts;
• vessels;
• liver;
• lungs.

In inflammatory processes, antibiotics and non-steroidal anti-inflammatory drugs are prescribed. In very severe cases, a surgical intervention is prescribed, which is aimed at eliminating the pathological process.

Possible complications

Such a disease can be triggered by an already existing ailment, being one of its symptomatic manifestations and aggravating the clinical picture.

The consequences of the pathology are as follows:

• the functioning of organs, systems, tissues is disrupted;
• deformation occurs in the places of localization of hyalines;
• contributes to the appearance of heart disease, aggravation of diabetes, impaired vascular patency;
• causes inflammation.

At the first deviations from the norm and the appearance of the above symptoms, you should contact the clinic for help, since hyalinosis of the spleen capsule, like any other form, leads to serious consequences.

Prophylaxis

The best prevention would be to maintain a healthy lifestyle, timely treatment of all diseases, proper nutrition and a preventive medical examination.