This document discusses different types of cell death known as necrosis. It defines necrosis as irreversible damage to cells that cannot be corrected and involves failure of ATP generation, membrane damage, and damage from reactive oxygen species. The document outlines several patterns of necrosis including coagulative necrosis where tissue architecture is preserved, liquefactive necrosis where tissue turns into a viscous liquid, and caseous necrosis where tissue has a cheesy, yellow-white appearance. It also discusses specific forms of necrosis that can occur in conditions like infections, gangrene, acute pancreatitis, and immune reactions.

4. I. Form of cell death
 CELL MEMBRANE fell apart
 CELLULAR ENZYMES leak out
which digest cell
 Culmination of REVERSIBLE
INJURY that cannot be corrected
DEFINATION

5. Failure of energy generation in the form of ATP
 reduced O2 supply
 mitochondrial damage
Damage to membranes leakage of cellular
lysosomal membrane contents including
plasma membrane ENZYMES
 IRREVERSIBLE DAMAGE to cellular lipid ,proteins
,nucleic acids caused by reactive oxygen species
MECHANISM

6.  cell show increased EOSINOPHILIA
 loss of BASOPHILIC NUCLEIC ACID (RNA & DNA) in cytoplasm
 cell may have appearance loss of staining
GLASSY GLYCOGEN particle
HOMOGENEOUS
 MYELIN FIGURES more prominent in necrotic cell than cell
with reversible injury
 CYOPLASM becomes VACUOLATED
 Discontinuity in plasma and organelle membranes
 Dilation of MITOCHONDRIA appearance of amorphous intramito-
chondrial densities
 disruption of LYSOSOMES
CYTOPLASMIC CHANGES DURING
NECROSIS

7. It occurs in 3 patterns
 PYKNOSIS nuclear shrinkage
DNA shrunk into dark mass
increased basophilia
KARYORRHEXIS pyknotic nucleus undergoes destructive
fragmentation
 KARYOLYSIS basophilia fades due to digestion of
DNA by deoxyribonuclease (DNAse)
In 1-2 days nucleus is completely dead and disappears
NUCLEAR CHANGES

8. FATE OF NECROTIC CELL
may be digested by ENZYMES and disappears
may persist for sometimes
MYELIN FIGURE phagocytized by other cell
further degraded into FATTY ACID
which binds with CALCIUM to form
CALCIUM SALT
dead cell is CALCIFIED

9. Comes from
LYSOSOMES of DYING CELL
LEUKOCYTES as a part of
INFLAMMAION
REACTION

10. NECROSIS
&
TYPES

11.  affected tissue takes firm structure
 tissue architecture is preserved several days after cell death
 denatured STRUCURAL PROTIENS and ENZYMES
block PROTOLYSIS of cell EOSINOPHILIC ,
ANUCLEATE CELL persist
for days and weeks
 LEUKOCYTES digest cell by LYSOSOMAL ENZYMES
 CELL DEBRIS is phagocytized primarily by MACROPHAGES
NEUTROPHILS
 characteristic of INFARCT : occur in all solid organs except BRAIN
COAGULATIVE NECROSIS

13.  seen in BACTERIAL INFECTION
occasionally in FUNGAL INFECTION
 also evoked by HYPOXIC DEATH of cells in CNS
Dead cells are completely digested transforming tissue into
VISCOUS LIQUID
 if initiated by active inflammation i.e. BACTERIAL INFECTIONS
the material is frequently CREAMY and YELLOW
PUS
LIQUEFACTIVE
NECROSIS

15.  no distinctive pattern of CELL DEATH
 used to refer condition of limbs usually LOWER LIMBS
that has lost BLOOD SUPPLY undergone COAGULATIVE
necrosis
MULTIPLE TISSUE LAYERS
 when superimposed by BACTERIAL INFECTION
destructive content of BACTERIA and attracted LEUKOCYTES
morphologic appearance changes WET
to LIQUEFACTIVE necrosis GANGRENE
GANGRENOUS NECROSIS

17. o CASEOUS CHEESE like
o GROSS appearance of necrosis site FRIABLE YELLOW--WHITE
o most often encountered in foci of TUBERCUOLOSIS infection
o microscopic examination collection of fragments of lysed
cells
amorphous granular PINK appearance in H&E stained tissue
o Tissue architecture is completely obliterated ; cellular lines can't
be discerned
o often surrounded by MACROPHAGES and other inflammatory
cells characteristic of NODULAR inflammatory lesions
GRANULOMA
CASEOUS NECROSIS

19. • refers to focal area of fat destruction
• resulting from release of ACTIVATED PANCREATIC
LIPASE into the substance of pancreas and peritoneal
cavity
• Occur in calamitous abdominal emergency
ACUTE PANCREATITUS
pancreas enzymes leak out of ACINAR cells and DUCTS
liquefy membrane off FAT cells in peritoneum
LIPASES splits TRIGLYCERIDES ESTER contained
in FAT CELLS
released fat join with calcium to produce CHALKY
WHITE AREAS FAT SPONIFICATION
FAT NECROSIS

20. • FOCI of necrosis contain shadowy outline of
NECREOTIC CELL surrounded by CALCIUM DEPOSITS

21.  special form of NECROSIS
 only necrosis which is examined only by HISTOLIGIC
examination not by appearance
 occur in IMMUNE REACTIONS in which complexes of
antigens and antibodies are deposited in the wall of
vessels
 may occur in severe HYPERTENSION
 deposited Immune complexes and plasma protein produce
PINK AMORPHOUS appearance on H&E preparation
FIBRINOID
FIBRINOID NECROSIS