GENERAL PATHOLOGY Calcification hhkgg.ppt

GENERAL PATHOLOGY Calcification hhkgg.ppt

1. Calcification
About 99 percent of your body’s calcium is in your teeth and bones.
The other 1 percent is in the blood, muscles, fluid outside the cells,
and other body tissues .

2. Pathologic calcification
Pathologic calcification refers to the abnormal deposition of calcium
salts, typically as phosphates or carbonates, in soft tissues
(i.e., tissues that would not be calcified in a healthy state).
This buildup can harden & disrupt the body’s normal processes .

3. Type of calcification
1. Dystrophic calcification is deposition of calcium in degenerating
or dead tissues, though serum levels of calcium remain normal
(normal calcium metabolism).
This type of calcification is seen in:
a-areas of necrosis ,dying and dead tissue.
b-atherosclerotic plaques
c- aging or damaged heart valves.

4. Sources and Consequences of Increased Cytosolic Calcium in Cell
Injury: Loss of the ability to regulate cellular Ca2+ balance is a critical
turning point that converts reversible to irreversible injury.

5. Calcification, Vitamin E or
Selenium Deficiency, Heart,
Lamb. The chalky white
lesions are areas of myocardial
necrosis that have
been calcified.

6. Calcification of the skin is categorized as
(1)Calcinosis cutis, a poorly understood form of epithelial and
collagenous calcification seen mainly in canine hyperglucocorticoidism,
and
(2)Calcinosis circumscripta. is a localized deposit of calcium salts in the
dermis or subcutis, in other soft tissues or in the tongue.
It is common over bony prominences of distal aspects of the limbs
in young dogs of the large breeds (e.g., horses).
It is probably a form of dystrophic calcification and usually attributed
to repetitive trauma.

7. Metastatic calcification is deposition of calcium salts in normal
living tissue, with elevated serum levels of calcium, which can occur
because abnormal calcium metabolism(hypercalacemia).
This type of calcification happens anywhere in the body but
principally affects the interstitial tissues of the vasculature, kidneys,
lungs, and gastric mucosa.
Metastatic calcification is often found in many tissues , whereas
dystrophic calcification is localized.
.

12. Antagonistic action of
Calcitonin in response
to hypercalcemia

13. The primary defect is an imbalance in calcium and phosphate
concentrations in the blood.
In chronic kidney disease / Renal failure, phosphate retention is the
cause of the calcium-phosphate imbalance.
Toxicosis with vitamin D or its analogues is also characterized by
calcium-phosphate imbalance.
Inappropriately elevated concentrations of parathyroid hormone
(PTH) or secretion of PTH-related peptide cause hypercalcemia
and metastatic calcification

14. Macroscopically
Metastatic calcification targets the intima and tunica media of vessels,
especially those in the lungs, pleura, endocardium, kidneys, and
stomach.
If calcification is extensive, it appears grossly as chalky white deposits
with a brittle or gritty texture.
Microscopically

Both the types of calcification appear as intracellular and /or extra
cellular (bluish) deposits as seed surrounding with ca+ layers.
The von Kossa histochemical technique blackens the calcium
phosphate or calcium carbonate salts.

15. Calcification, Stomach, Dog. A band of calcification is in the middle of the gastric
mucosa. A, The calcium salts are basophilic (stained blue with hematoxylin). H&E
stain.

16. Calcification, Stomach, Dog. A band of calcification is in the middle of the gastric
mucosa. A, The calcium salts are black with the von Kossa technique for
mineralization