If you see a golden brown, slightly refractile pigment on routing light H&E microscopy, it is either hemosiderin, melanin, or bile derived. A few other degenerative pigments, such as lipofucsin, are also possible. Special stains can prove it is one or the other, if it is not abundantly clear from its cellular or pathologic setting and/or location
This tiny amount of microscopic tattoo pigment can make white skin look quite black! Is this EXogenous or ENDogenous?
Why does anthracosis look worse along the pleural surface than on cut sections? Why are MANY extrathoracic lymph nodes also anthracotic? What in the body is black and NOT due to EXOGENOUS pigments?
Why would somebody order a prussian blue stain, or a S-100 immunoperoxidase stain or a HMB-45 stain?
PATHOLOGICAL CALCIFICATION Definition:- Abnormal deposition of calcium saltstogether with smaller amount of Mg++ ,Fe++ &other minerals in tissues other than osteoid orenamel
Metastatic calcification reflects deranged calcium metabolismin contrast to dystrophic calcification andis associated with increase serum calciumlevel & systemic deposition of Ca++saltsin interstitial tissue of gastric mucosa,kidney,lungs,systemic arteries&pulmonary veins.
Metastatic calcification Hypercalcimia• Increased secretion of parathyroid hormone• Destruction of bone tissue 2ndry to primary tumor ofbone marrow ( multiple myeloma, leukemia), or diffuseskeletal metastasis.• Vitamin D-related intoxication• Renal failure•Excessive intake of calcium & absorbable antacids asmilk or calcium carbonate.
This is dystrophic calcification in the wall of the stomach. At the far left is an artery with calcification in its wall
“Metastatic calcification" in the lung of a patient with a very high serum calcium level (hypercalcemia).
PIGMENTSEX-ogenous--- (tattoo, Anthracosis)END-ogenous--- they all look thesame, (e.g., hemosiderin, melanin,lipofucsin, bile), in that hey are allgolden yellowish brown on “routine”Hematoxylin & Eosin (H&E) stains
Accumulation of Pigments• Exogenous pigments Carbon ( anthracosis) Coal dust ( pneumoconiosis) Lung: pick up by alveolar macrophages regional lymph nods blackening the tissues of the lungs (anthracosis)
Accumulation of Pigments• Endogenous pigment :Lipofuscin – aging pigment(fucus=brown) lipid, phospholipid-protein complex (lipid peroxidation) ,brown-yellow pigment accumulated as the atrophic and dying cells undergo autophagocytosis. Harmless,Sign of free radical injury & lipid perioxidation, seen in aging patients severe malnutrition & cancer cachexia.
Lipofuscin granules in a cardiac myocyte as shown by A, light microscope (deposits indicated byarrows) , and B,Electron microscopy (perinuclear ,intralysosomal location).
Lipofuscin (wear & tear) pigments in cardiac myocytes
Melanin• Melanin – melas= black• In melanocytes formed by oxidation of tyrosine to dihydroxyphenylalanine by tyyrosinase enzyme
Ageing:“Progressive time related loss of structural and functional capacity of cells leading to death”• Senescence, Senility, Senile changes.• Ageing of a person is intimately related to cellular ageing.
Ageing –changes:• Gradual atrophy of tissues and organs.• Dementia• Loss of skin elasticity• Greying and Loss of hair• BV damage – atherosclerosis/bruising.• Loss of Lens elasticity opacity vision• Lipofuscin pigment deposition – Brown atrophy in vital organs.