Metastatic calcification is deposition of calcium salts in otherwise normal tissue, because of elevated serum levels of calcium, which can occur because of deranged metabolism as well as increased absorption or decreased excretion of

calcium Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...

and related minerals, as seen in

hyperparathyroidism Hyperparathyroidism is an increase in parathyroid hormone (PTH) levels in the blood. This occurs from a disorder either within the parathyroid glands ( primary hyperparathyroidism) or as response to external stimuli ( secondary hyperparathyroi ...

. In contrast,

dystrophic calcification Dystrophic calcification (DC) is the calcification occurring in degenerated or necrotic tissue, as in hyalinized scars, degenerated foci in leiomyomas, and caseous nodules. This occurs as a reaction to tissue damage, including as a consequenc ...

is caused by abnormalities or degeneration of tissues resulting in mineral deposition, though blood levels of calcium remain normal. These differences in pathology also mean that metastatic calcification is often found in many tissues throughout a person or animal, whereas dystrophic calcification is localized. Metastatic calcification can occur widely throughout the body but principally affects the interstitial tissues of the vasculature, kidneys, lungs, and gastric mucosa. For the latter three, acid secretions or rapid changes in pH levels contribute to the formation of salts.

Causes

Hypercalcemia, elevated blood calcium, has numerous causes, including # Elevated levels of parathyroid hormone due to

, leading to

bone resorption Bone resorption is resorption of bone tissue, that is, the process by which osteoclasts break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone tissue to the blood. The osteoclasts are multi-nuclea ...

and subsequent hypercalcemia by reducing phosphate concentration. # Secretion of

parathyroid hormone-related protein Parathyroid hormone-related protein (PTHrP) is a proteinaceous hormone and a member of the parathyroid hormone family secreted by mesenchymal stem cells. It is occasionally secreted by cancer cells (for example, breast cancer, certain types of ...

by certain tumors. # Resorption of bone due to #* Primary bone marrow tumors (e.g.

multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibody, antibodies. Often, no symptoms are noticed initially. As it progresses, bone ...

and

leukemia Leukemia ( also spelled leukaemia; pronounced ) is a group of blood cancers that usually begin in the bone marrow and produce high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or '' ...

) #* Metastasis of other tumors, breast cancer for example, to bone. #* Paget disease #* Immobilization #

Vitamin D Vitamin D is a group of structurally related, fat-soluble compounds responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, along with numerous other biological functions. In humans, the most important compo ...

related disorders ## Vitamin D intoxication ##

Williams syndrome Williams syndrome (WS), also Williams–Beuren syndrome (WBS), is a genetic disorder that affects many parts of the body. Facial features frequently include a broad forehead, underdeveloped chin, short nose, and full cheeks. Mild to moderate int ...

(increased sensitivity to vitamin D) ##

Sarcoidosis Sarcoidosis (; also known as Besnier–Boeck–Schaumann disease) is a disease involving abnormal collections of White blood cell, inflammatory cells that form lumps known as granulomata. The disease usually begins in the lungs, skin, or lymph n ...

Kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

References

Histopathology {{pathology-stub