Theme 2 MESENCHYMAL DYSTROPHY

Mesenchymal dystrophy: develop as a result of metabolic disorders in the connective tissue and are detected in the stroma of organs and the vascular wall.

Protein (disproteinois), Fat (lipidosis), Carbohydrate. Mesenchymal dystrophies are divided into: Protein (disproteinois), Fat (lipidosis), Carbohydrate.

Stromal-vascular proteindystrophy can be divided into: mucoid swelling, fibrinoid swelling, hyalinosis, amyloidosis.

Mesenchymal protein dystrophies:

Mucoid swelling - superficial and reversible disruption of the connective tissue. In the intercellular matter there is material accumulation and redistribution of glycosaminoglycans (hyaluronic acid). It is characterized by the phenomenon of metachromasia (the ability of tissue to be painted in a color different from the dye (due to accumulation of chromotropic substances). The outcome: restoration or transition to the fibrinoid swelling.

The phenomenon of metachromasia (toluidine blue stain)

Fibrinoid swelling a deep and irreversible degeneration of the connective tissue as a result of destruction of the intercellular substance, accompanied by increased vascular permeability and the formation of fibrinoid (proteins, polysaccharides, cell nucleoproteins). The outcome: necrosis, sclerosis, hyalinosis.

Fibrinoid swelling with the outcome of fibrinoid necrosis in the mitral valve of the heart

Hyalinosis: In this degeneration homogeneous semi-solid mass resembling hyaline cartilage are formed in the connective tissue formed. Classification: hyalinosis of vessels, hyalinosis of connective tissue.

Types of vascular hyaline: Simple (components of blood plasma and the decay products of the vessel wall) (occurs on hypertension, atherosclerosis). Lipohyalin (contains lipids and β - lipoproteins) (occurs on diabetes mellitus). Complex (contains immune complexes, fibrin, elements of degenerated vessel wall) (occurs on rheumatic diseases). Hyalinosis of connective tissue develops as the outcome of fibrinoid swelling. The outcome in most cases is unfavorable, but sometime resorption of hyaline masses is possible.

(mesenchimal dysproteinosis) Hyalinosis (mesenchimal dysproteinosis)

Hyalinosis of the heart valve and the wall of brain small artery

Amyloidosis - stromal-vascular degeneration, accompanied by a severe violation of protein metabolism, formation of abnormal fibrillar protein and complex substance – amyloid in the interstitial tissue and vascular walls. Amyloid is composed of the F-component (fibrillar protein) and P - component (glycoproteins of blood plasma).

Classification: Depending on the etiology of release: Primary (idiopathic) Hereditary (genetic) Acquired (secondary) Senile

In view of the affected organs and systems: cardiomyopathic, nephropathic, neuropathic, retinopathic, hepatopathic, mixed, of the APUD – system.

Depending on the type of fibers along which amyloid is deposited there are distinguished: periarticular amyloidosis (parenchymatous) - delayed along of reticular fibers. pericollagen amyloidosis (mesenchymal) - delayed in the course of collagen fibers.

Types of amyloidosis: AL - amyloidosis - Primary amyloidosis caused by the accumulation in plasma of abnormal light chains of immunoglobulins synthesized by B - lymphocytes in multiple myeloma. amyloidosis - secondary amyloidosis, caused by hypersecretion of hepatic acute phase protein alpha-globulin in response to chronic (often suppurative) inflammation (bronchiectasis, tuberculosis). It has a subtype - ASC - amyloidosis. AA -

amyloidosis - hereditary form of amyloidosis with an autosomal recessive mechanism. It occurs in certain ethnic groups (Armenians, Jews, Arabs). AF - AH - amyloidosis (hemodialisis - related) - only in patients on hemodialysis (beta 2-microglobulin of MHC class that is not filtered in gemodializator and accumulates in the body.

The causes of secondary amyloidosis: Rheumatic disease (rheumatoid arthritis) Malignant neoplasms (multiple myeloma, Hodgkin's disease, some types of cancer) Purulent processes (lung abscesses, bronchiectasis, osteomyelitis, suppuration of wounds, etc.) Some of the chronic infectious diseases (tuberculosis)

Amyloidosis of the spleen Sago spleen

Amyloidosis of the spleen

Amyloidosis of the spleen Lardaceous spleen

Amyloidosis of the kidney

Mesenchymal fatty dystrophy Mesenchymal fatty degeneration result from the neutral fats and esters metabolism violation. Violation of the exchange of neutral fat is characterized by increase their reserves in the adipose tissue. It can be general and local.

Overall obesity - increase of neutral fat number in the fat depot (subcutaneous tissue, omentum, mesentery, mediastinum). Etiology: The primary form, The secondary form (cerebral, endocrine, and hereditary diseases).

Types: symmetrical type, superior type, middle type, inferior type. Morphological classification: hypertrophic type (increased sizes of fat cells), hyperplastic type (increased number of fat cells).

Obesity

Heart obesity

Lipomatosis - local increase of the adipose tissue amount (Dercum`s disease - appearence of painful nodular deposits of fat in the subcutaneous tissue of extremities and trunk). Vacatous obesity - occurs on tissue or organ atrophy (fatty replacement of the thymus gland).

Reduced fat stores may be general (cachexia (alimentary, cancer, pituitary, cerebral, infection)) or the local character (regional lipodystrophy, when fat necrosis is observed. It names lipogranulema).

Violation of cholesterol and its esters leads to the development of atherosclerosis with the fibrous plaque formation. It narrows the lumen of the vessel.

Mesenchymal carbohydrate dystrophy are associated with metabolic disorders of glycoproteins and glycosaminoglycans. Violation of glycoproteins metabolism – sliming – is characterized by replace of collagen fibers by mucoid mass (in contrast to the mucoid swelling). Reasons of sliming: dysfunction of the endocrine glands (myxedema), cachexia of various origin.

An inherited disorders of glycosaminoglycans are the basis of mucopolysaccharidosis. Among them gargoilizm, or Fudler – Hurler`s disease has a grate clinical value. It is characterized by disproportionate growth, deformation of the skull, heart defects, inguinal and umbilical hernias, keratoleukoma (nebula), hepato-and splenomegaly).

Study the micropreparations

№13-а“Hyalinosis of vessels and scar at the place of yellow body of the ovary”

№17-а “Sago spleen”

№15 “Kidney amyloidosis”. b

№22 “Heart obesity”

Necrotic debris (atheromatosis) №27 “Atherosclerosis of aorta” №27-а. “Atherosclerosis of artery”. Necrotic debris (atheromatosis) Foam cells