Ninety-nine percent of the calcium in the body is used to build strong bones and teeth. The remaining calcium circulates in the organs, tissues and bloodstream. In certain situations, calcium deposits can accumulate in various tissues of the body, either in specific locations or in a widespread pattern. Calcium deposition is sometimes harmless, but in other situations, it can indicate an underlying abnormality or disease. The two main causes of calcification and calcium deposition outside the bones are tissue damage and an elevated calcium level in the body. Several medical conditions can trigger the situations.
Small-Scale Tissue Damage
Calcification can occur from local tissue damage when calcium blood level is normal. Tissue damage triggers signals that attract calcium into the damaged tissue. There are several types of small-scale tissue damage that cause calcification. Blood vessel calcification is a common example. This type of calcification occurs in damaged tissues of the arteries as part of the condition known as atherosclerosis. Damaged areas in the arteries accumulate fat and other substances, forming a deposit called a plaque that becomes calcified over time. Plaques lead to narrowing of the arteries and can provoke clot formation. Atherosclerotic plaques often lead to heart attack, stroke or kidney failure.
The formation of calcium deposits in the breast is another common example of small-scale tissue damage leading to calcification. In most cases, the calcification is related to a noncancerous process, such as fibrocystic breast changes. In some instances, however, calcium deposits in the breast are a sign of cancer.
Large-Scale Tissue Damage
Large-scale tissue damage is associated with extensive loss of cells, a situation referred to as tissue necrosis. As with smaller-scale damage, the death of tissue in a specific area of the body leads to release of signaling factors that attract cells to clean up and heal the dead tissue. This process, known as an inflammatory response, attracts calcium into the damaged area as it heals. This can lead to permanent calcification. Infections are a possible causes of this type of tissue calcification, which is often seen in the lungs. Calcification is also sometimes seen around the heart associated with a condition called pericarditis.
Protracted or repeated tissue damage with accompanying inflammation can also cause tissue calcification. Calcium deposits of this type often occur in the tendons of the shoulders, ankles or knees. They also often occur with chronic pancreatitis, in which the organ is persistently inflamed, usually due to excessive alcohol intake. Calcification from tissue death can also result from blunt trauma to the body.
Calcification From Elevated Calcium Level
Calcification occurring from a high blood calcium level involves a different mechanism, which typically leads to widespread distribution of calcium deposits in various areas of the body. When there is too much calcium in the bloodstream, it can no longer remain dissolved in the liquid portion of the blood and begins to deposit in the tissues of the body.
Hyperparathyroidism -- a hormonal disorder that causes calcium from the bones to move into the bloodstream -- is an example of a condition that can lead to widespread calcium deposits in the body. Bone destruction due to tumors or diseases can also release excessive calcium into the bloodstream and trigger calcium deposits in body tissues. Longstanding kidney failure and excessive intake of vitamin D, which results in excessive absorption of calcium from the intestines, can also lead to this type of calcification.
Warnings and Precautions
Calcification in the body tissues usually causes no symptoms. However, a high calcium level can cause symptoms, such as weakness, nausea, vomiting, poor appetite, confusion or drowsiness. Chest pain, joint or muscle aches and bone pain are also possible with some conditions. If you experience any of these symptoms, see your doctor as soon as possible. In many cases, tissue calcification is harmless -- but if treatment is needed, the therapy will depend on the underlying cause of the problem and the tissues affected.