General mechanisms

• Abnormal metabolism(fatty change)

• Protein mutations(abnormal proteins)lack of enzymes –lysosomal storage

• Inability to degrade ingested particles-exogenous/endogenous pigments

Icterus skin

Fatty streak

Fat necrosis pancreas

Normal fat

Necrotic fat near pancreas

Fatty change

bilirubin

lipofuscin

lipochrome

melanin

melanin

Alpha 1 antitrypsin

•

Glycogen PAS

hemosiderin

Prussian blue liver

Prussian blue renal tubule

Congo red amyloid

gaucher

anthracosis

Apoptosis liver

Foetal thymus apoptosis

Liquifaction necrosis

Celldeath myocardium

• When there is marked cellular injury, there is cell death. This microscopic appearance of myocardium is a mess because so many cells have died that the tissue is not recognizable. Many nuclei have become pyknotic (shrunken and dark) and have then undergone karorrhexis (fragmentation) and karyolysis (dissolution). The cytoplasm and cell borders are not recognizable.

Metastatic calcification

Dystrophic calcification stomach