Degeneration, or dystrophy, is a pathological process that causes changes in the structure of cells and tissues due to disturbances in cellular or tissue metabolism. There are two main types of mechanisms that can cause degenerations - cellular mechanisms involving enzymes and autoregulation, and extracellular mechanisms involving transportation and endocrine systems. Degenerations are classified based on their localization, type of metabolic disturbance, origin, and propagation. Common types of degenerations include parenchymatous degenerations involving intracellular accumulation, mesenchymatous degenerations involving extracellular accumulation, and mixed degenerations. Parenchymatous degenerations can be albuminous, fatty, or carbohydrate depending on the specific metabolic pathway affected.

1. DEGENERATIONS
(dystrophy)

2. Degeneration (dystrophy)
is a pathological process due to
disturbance of either cellular or
tissue metabolism which causes
changes in the structure of cells,
tissues, etc.

3. Trophism mechanisms are cellular and
extracellular:
cellular: autoregulation (enzymes)
extracellular: transportation systems
(blood, lymph); endocrine regulation;

4. Morphogenetic mechanisms of degenerations:
 infiltration: abundant invasion of metabolite
products from the transportation system to the cell
followed by their accumulation;
 decomposition: destruction of cellular
ultrastructure (lipoprotein complex from cellular
membranes) with accumulation within a cell;
 abnormal synthesis: intracellular synthesis of the
substances which are not produced normally (e.g.
amyloid);
 transformation: formation of products of one type
of metabolism from the common primary products,
e.g. increased polymerization of glycogen from
glucose.

5. Classification of degenerations
 According to the localization:
a) parenchymatous (intracellular accumulation),
b) mesenchymatous (extracellular accumulation),
c) mixed type.
 According to the type of metabolism disturbance:
a) albuminous (protein),
b) fatty (adipose), (lipidosis),
c) carbohydrate,
d) mineral
 According to the origin:
a) acquired,
b) heriteted.
 According to propagation
a) general,
b) local.

6. Parenchymatous degenerations
Parenchymatous albuminous
degenerations (dysproteinoses)

7. The modern classification of
parenchymatous albuminous
degenerations:
1) hyalin-drop
2) hydropic (edematous, balloon)

8. Hyalin-drop degeneration
Microscopically: rounded, eosinophilic
droplets, vacuoles, or aggregates in the
cytoplasm
Macroscopically: not changes
Localizations: kidney, liver,
myocardium

10. Hydropic degeneration
 Microscopically: large vacuoles of cytoplasm
fluid in the cytoplasm, the nucleus which
displaced to the peripheral areas
 Macroscopically: not changes
 Localizations: kidneys, skin, liver, muscles,
nerves

11. Horny degeneration
abundant formation of horny substance
in keratinized epithelium
(hyperkeratosis and ichtyosis)
appearance of horny substance in the
places where is not found under normal
conditions (leukoplakias)

13. Parenchymatous degenerations
Parenchymatous fatty
degenerations

14. Manifestation
of disturbance of fat metabolism:
appearance of fat in the place where it
does not appear under normal
conditions (e.g. in the myocardium),
appearance of fat of unusual
composition;
increase of fat amount in the places
where it is present under normal
conditions (e.g. in the fat depots).

15. Hypoxia - the main cause of fatty
degeneration
disturbances in transportation systems
(e.g. in patient with chronic
cardiovascular and chronic pulmonary
insufficiency);
chronic intoxications (e.g. alcoholism);
cachexia, avitaminosis;
infections (e.g. diphtheria, tuberculosis).

19. Parenchymatous degenerations
Parenchymatous carbohydrate
degenerations

20. Glycogen metabolism disturbance
increase or reduction in the amount in
the tissues where it is present under
normal conditions,
its appearance in the areas where it is not
present under normal conditions

21. Storage diseases
(enzymopathy)
proteinoses
lipidosis
glucogenoses

22. Thank you for your attention