Necrosis components / Exudates

necrosis cause: Ischemia, free radicals, toxins, burns, x-rays, Nutritional (WMD = Vit E + selenium deficiency)

coagualative

necrosis cause: Toxins of certain microorganisms (tuberculosis)

caseous

necrosis causee: ischemia, free radicals, toxins, burns, x-rays

liquefactive

necrosis cause: Infection, Coagulative + liquefactive combo, Distal extremities or dependent parts of organs

wet gangrene

necrosis cause: Loss of blood supply resulting in coagulative necrosis, Distal extremities or dependent parts of organs

dry gangrene

necrosis cause: Enzymatic, traumatic, idiopathic, nutritional (yellow fat dz, stealitis)

fat

necrosis gross appearance: Grey/white (unless mixed w/ blood), Depressed compared to surrounding tissue

coagulative

necrosis gross appearance: Cheese, milk curds, dry greasy, breaks easily

caseous

necrosis gross appearance: CNS! Abscesses/cavities containing yellowish fluid Necrotic tissue converted to liquid

liquefactive

necrosis gross appearance: Red+black WET tissue

wet gangrene

necrosis gross appearance: Dry, leathery, hard, MUMMIFICATION (no bacterial involvement)

dry gangrene

necrosis gross appearance: White, opaque, granular

fat

necrosis histological appearance: outline of necrotic cell = preserved

acidophilic/eosinophilic cytoplasm

Nuclear changes

 -Pyknosis - Shrunk, round dark 

 -Karyorrhexis - fragmented

 -Karyolysis - Dissolution

coagulative

necrosis histological appearance:

Granular stains purple Loss of cell outline, normal tissue architecture

caseous

necrosis histological appearance: Clear spaces with or without pink staining

Proteinaceous precipitate in necrotic area

Leukocytes present and produce hydrolytic enzymes

liquefactive

necrosis histological appearance: Shadowy outline w/ blue or purple (calcification) in areas of necrosis

Adipose tissue with saponification

fat

necrosis

caseous

necrosis

caseous

necrosis

liquefactive

necrosis

liquefactive

necrosis

fat

necrosis

fat

necrosis

dry gangrene

necrosis

wet gangrene

necrosis

coagulative necrosis

necrosis

coagulative necrosis

whats arrow 1

pyknosis

whats arrow 2

karyolysis

whats arrow 3

keryorrhetic

Cell shrinkage, fragmentation, NO INFLAMMATION

apoptosis

membrane rupture, INFLAMMATION, protein denaturation, dead contiguous cell

necrosis

extrinsic initiation phase apoptosis

death receptor initiated

intrinsic apoptosis initiation phase

mitochondrial

what activates apoptosis

capsase 3 cascade

exudate: clear straw colored fluid in cavities, skin, lungs or mucosal surfaces

Microscopically: very few cells, homogenous, pink (many soluble proteins)

Often seen in  mild/early injury that causes increased vascular permeability

serous

exudate: red tinged fluid because of widespread diapedesis/mild vascular damage

serohemorrhagic

exudate: clear, snot-like consistency from mucous membranes in GI, Resp or urogenital tract

Goblet cell hypertrophy/hyperplasia

Microscopically: deep purple, trapped air, fat and leukocytes

catarrhal

exudate: Thick, yellow, opaque → often bacterial component, (Pyo-) often prefix Associated with Abscesses

Microscopically: Neutrophils! With liquefactive necrosis due to granulation and digestion by non-specific enzymes

purulent / suppurative

con of purulent exudate

Massive destruction of host tissue

exudate: pale, flat, no fluid

lymphoplasmacytic

exudate: white, solid, raised tissue 

distinct aggregates of macrophages that surround and wall off an inciting cause (pathogen, foreign material) → over time, becomes encapsulated with connective tissue (often has necrotic center)

granulomatous

2 types of chronic exudates

lymphoplasmacytic and granulomatous

hemorrhage by diapedesis

is the escape of blood cells through the walls of small vessels into surrounding tissues, often resulting in localized bleeding and tissue damage.

true hemorrhage

is the escape of blood from a vessel into body spaces or tissues, leading to significant bleeding. This can occur due to trauma, rupture of a blood vessel, or erosion of a vessel wall.

hemorrhage type

hemorrhage by diapedesis

hemorrhage type

true hemorrhage

exudate

serous

exudate

serous

exudate

fibrinous

exudate

fibrinous

exudate

fibrinous

exudate that can be pulled off like a string; involved in clotting and is an acute exudate in inflammation

fibrinous

describes connective (scar) tissue, a chronic sequela of fibrin that is involved in healing -Cannot be pulled off

fibrous

exudate

catarrhal

exudate

catarrhal

exudate

catarrhal

exudate

catarrhal

exudate associated with Gastrointestinal tract Respiratory tract Urogenital tract

catarrhal

exudate

catarrhal

exudate

purulent/suppurative

exudate

purulent/suppurative

exudate

purulent/suppurative

exudate

purulent/suppurative

exudate

suppurative

exudate

serous

exudate

catarrhal

exudate

Fibrinopurulent

exudate

Serohemorrhagic