Over 99 percent of calcium in the body is used to build strong bones and teeth. The remaining calcium is found circulating in the bloodstream. In certain situations, calcium deposits accumulate in various tissues and organs. Calcium deposits are sometimes harmless, but in other situations, they indicate the presence of an underlying abnormality or disease. The two main causes of calcification and calcium deposits outside bones are tissue damage and excessive amounts of calcium in the bloodstream. Several medical conditions can trigger these situations.
Small-Scale Tissue Damage
Tissue damage causes inflammation that triggers signals attracting calcium to the area. This leads to calcium deposits in the damaged tissue. Several types of small-scale tissue damage can cause calcification.
Blood vessel calcification is a common example. This type of calcification occurs in damaged areas of arteries as part of the condition known as atherosclerosis. The damaged areas accumulate cholesterol and other substances, forming a deposit called a plaque. Over time, calcium collects in the plaque. Atherosclerotic plaques narrow the arteries and may trigger the formation of blood clots. They can lead to a heart attack, stroke or kidney failure.
Calcium deposits in the breast are another example of small-scale tissue damage producing calcification. Usually this calcification is caused by a noncancerous process, such as fibrocystic breast changes. But in some instances, calcium deposits are a sign of cancer.
Large-Scale Tissue Damage
With large-scale tissue damage, many cells die, producing tissue necrosis. As with small-scale damage, the area becomes inflamed and triggers signals leading to calcium accumulation in the damaged tissue.
Infections, especially certain infections in the lungs, can cause large-scale tissue calcification. Calcification can also occur with pericarditis, a disorder producing inflammation of the membrane surrounding the heart known as the pericardium. Pericarditis is often caused by a viral infection.
Prolonged or repeated tissue damage can cause tissue calcification. Calcium deposits of this type often occur in tendons around the shoulders, ankles or knees as the tendons become damaged and inflamed with repeated joint movements. They may also occur with chronic pancreatitis, a disorder characterized by persistent inflammation of the pancreas, which is usually caused by excessive alcohol intake.
A traumatic injury to almost any area of the body may lead to large-scale damage and calcium deposits.
High Blood Calcium Level
When there is too much calcium in the bloodstream, the calcium can no longer remain dissolved in the blood and will begin to deposit in various tissues and organs.
Hyperparathyroidism -- a hormonal disorder causing calcium to move from bones into the bloodstream -- causes high blood levels of calcium and widespread calcium deposits.
Bone destruction by tumors or certain bone diseases can also release excessive calcium into the blood, triggering calcium deposits in various areas. Other causes include longstanding kidney failure and consuming large amounts of vitamin D, which leads to excessive absorption of calcium from the intestines.
Warnings and Precautions
Calcification in body tissues usually causes no symptoms. However, a high calcium level in the blood can produce 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, calcification and calcium deposits outside bones are harmless. But if treatment is needed, therapy will depend on the underlying cause and body areas affected.
Reviewed by Mary D. Daley, M.D.
- Kidney International: Recent Progress in the Treatment of Vascular Calcification
- Benign Breast Diseases: Radiology, Pathology, Risk Assessment, Second Edition; Catherine N. Chinyama
- Skin and Systemic Disease: A Clinician’s Guide; Joseph C. English III et al.
- Scientific World Journal: Vascular Calcification and Renal Bone Disorders
- Rheumatic Diseases Clinics of North America: Mechanisms of Pathologic Calficiation
- University of Washington Department of Radiology: Soft Tissue Calcifications
- Cells, Tissues, and Disease: Principles of General Pathology, Second Edition; Guido Majno and Isabelle Joris
- Dietary Reference Intakes for Calcium and Vitamin D; Catharine Ross, et al.
- Merck Manual Professional Version: Chronic Pancreatitis
- Mayo Clinic: Pericarditis