High blood calcium (Hypercalcemia)

Dr. Nicholas Kaloudis

Calcium is a mineral found mostly in your bones, where it builds and maintains bone strength. A small amount of calcium is also found in muscle and blood cells, where it plays several important roles: It helps muscles contract, it helps nerves and the brain work properly, and it helps regulate your heart rhythm and blood pressure.

High blood calcium often leads to osteoporosis, and kidney stones. Very high blood calcium can cause more serious problems, including kidney failure, abnormal heart rhythm, mental confusion, and even coma.

Normally, your body controls blood calcium by adjusting the levels of several hormones. When blood calcium levels are low, your parathyroid glands(4 pea-sized glands in your neck) secrete a hormone called PTH (Parathyroid hormone). PTH helps your bones release calcium into the blood.

Vitamin D is also important in keeping calcium levels in the normal range. Vit.D, which is actually a hormone, helps your body absorb calcium and move it from your intestines into your blood. Together, PTH and Vit.D along with other hormones and minerals, help move calcium in or out of body tissues to keep your blood calcium at a normal level.

The most common cause of high blood calcium is a condition called Primary Hyperparathyroidism. In this condition, one or more of the parathyroid glands enlarges and produces too much PTH. This, in turn, causes the bones to release too much calcium into he blood.

Certain types of cancer, like breast, lung or blood, can also cause high blood calcium. Less common causes of hypercalcemia include these health problems: Some types of infectious diseases such as TB, certain types of autoimmune disease, such as sarcoidosis, and certain hormone disorders, such as hyperthyroidism.

Some medications, such as lithium or thiazide diuretics, intake of very large amounts of calcium or large amounts of milk plus antacids, intake of too much Vit. A or Vit D, immobility, and severe dehydration can cause hypercalcemia.

Symptoms of hypercalcemia may range from none to muscle weakness, fatigue, constipation, nausea, confusion, and mood changes.

Doctors detect high blood calcium through a blood test that measures calcium levels. To help pinpoint the cause, your endocrinologist will check PTH and Vit.D levels, as well as kidney function, and the levels of calcium in your urine. Imaging studies also may be helpful, such as bone mineral density, and ultrasound.

Your treatment of hypercalcemia will depend on the cause. In general, the best treatment is to take care of the condition that is causing the high blood calcium. For instance, people with primary hyperparathyroidism who have symptoms usually have surgery to remove the enlarged parathyroid gland. When blood calcium is dangerously high, people may need treatment in a hospital to return their blood calcium to a safe level. You may not need any treatment if your blood calcium is only slightly elevated. Adequate fluid intake may be enough to keep your calcium levels stable. Your endocrinologist will continue to check your condition over time.