1.6. calcification-ppt. in cell injury. its a process of calcium builds up in body.

this can be normal or abnormal process.

1. calcification By – Dr. Arpita Acharia

2. What is calcification? it is a process in which calcium builds up in body tissue, causing the tissue to harden. This can be a normal and abnormal process.

3. PATHOLOGICAL CALCIFICATION Pathological calcification is abnormal deposition of CALCIUM salts with smaller amounts of IRON, MAGNESIUM and other minerals except teeth and bone`deposition .

4. MECHANISM OF CALCIFICATION Calcium deposits in the form of hydroxyapatite (natural occurring mineral form of calcium) and involves two phases INITIATION – initiation of calcium takes place in the matrix vesicles where calcium and phosphates accumulate. The matrix vesicles are extracellular membrane bound vesicles that bud off from other cells. PROPAGATION – The second phase involves further growth of hydroxyapatite

5. TYPES OF PATHOLOGIC CALCIFICATION DYSTROPHIC CALCIFICATION When deposition occurs in dead or dying tissue It occurs with normal serum level of normal calcium metabolism METASTATIC CALCIFICATION Deposition of calcium salts in normal tissue It almost always reflects some derangement in calcium metabolism and increase level of calcium(hypercalcemia)

6. DYSTROPHIC CALCIFICATION Dystrophic calcification is encountered in areas of necrosis of any type It is certain in atheromas of advanced atherosclerosis , associated with initial injury in the aorta and large arteries Although dystrophic calcification may be an incidental finding indicating in significant past cell injury , it may also be a cause of organ dysfunction For example-dystrophic calcification of aortic valve is an important cause of aortic stenosis in elderly

7. MORPHOLOGY OF DYSTROPHIC CALCIFICATION CALCIUM SALTS are grossly seen as fine white granules or clumps , often felt as gritty deposition Histologically calcification appears as intracellular and/or extracellular basophilic deposits In time heterotopic bone may be formed in the focus of calcification

8. SITES OF DYSTROPHIC CALCIFICATION NECROTIC TISSUE Caseous necrosis Fat necrosis Liquifactive necrosis Advanced atheromatous lesion Hematoma Thrombus Infarct Heart valve (example -sub acute infective endocarditis )

9. METASTATIC CALCIFICATION METASTATIC CALCIFICATION can occur in normal tissue whenever there is hypercalcemia Main cause of hypercalcemia 1. increase secretion of parathyroid hormone 2. Destruction of bone due to the effect of accelerated turn over ( paget’s disease) then immobilisation or tumor (multiple myeloma, leukemia or diffused skeletal metastasis ) 3. Vitamin D related disorder including vitamin D intoxication and sarcoidosis 4. Renal failure , in which phosphate retention leads to secondary hyperparathyroidism

10. SITE OF METASTATIC CALCIFICATION KIDNEY (BASEMENT MEMBRANE OF TUBULAR EPITHELIUM ) LUNGS (ALVEOLAR WALL) STOMACH (ACID SECREATING FUNDUL MUCOSAL GLANDS) BLOOD VESSELS ( INTERNAL ELASTIC LAMINA ) CORNEA SYNOVIAN (JOINT CAUSING PAIN AND DYSFUNCTION)

11. MORPHOLOGY METSTATIC CALCIFICATION can occur widely throughout the body but principally affects the interstitial tissue of the vasculature , kidney , lungs and gastric mucosa Calcium deposition morphologically resembled those described in dystrophic calcification

12. EFFECTS OF METASTATIC CALCIFICATION X ray of lungs show white shadow and cause respiratory deficit Massive deposits in kidney (nephron calcinosis)can cause stones and renal damages

13. DIFFERENCE DYSTROPHIC CALCIFICATION Deposition in dead and degenerated tissue Normal calcium metabolism Normal calcium level Generally irreversible Necrosis ,infarcts , thrombi , hematoma , old scars METASTATIC CALCIFICATION Deposition in normal tissue Deranged hypercalcemia Reversible upon correction of metabolic disorder Hyperparathyroidism , bony destructive lesions , hypervitaminosis D

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