Tutorial: Hypercalcemia (High Calcium Levels) and Parathyroid Disease
Hypercalcemia (High Calcium Levels) and Parathyroid Disease
The patient with a diagnosis of hypercalcemia and parathyroid disease is usually referred through their primary physician or endocrinologist. The patient often has minimal symptoms, and the elevated calcium levels might be discovered on routine lab work. Additionally, patients with kidney stones or osteoporosis should be screened for blood calcium levels. The patient with hypercalcemia will require evaluation of a number of possible causes of hypercalcemia. In a healthy patient (who may or may not have kidney stones), hypercalcemia is most commonly associated with primary hyperparathyroidism, a disease of the parathyroid glands.
There are four parathyroid glands, two on either side of the midline of the neck immediately adjacent to the thyroid gland. Each of these parathyroid glands is approximately the size of a pencil eraser and weighs about 30 milligrams. The parathyroid glands secrete a hormone called parathyroid hormone (PTH) which regulates the body's metabolism of calcium. The majority of patients with parathyroid disease have a non-familial enlargement of one or more parathyroid glands. When one or more of the parathyroid glands grows and enlarges for unknown reasons, it may produce too much parathyroid hormone. This results in elevated calcium levels in the blood. The calcium stores of the bones can be adversely affected by this situation. This is particularly significant in postmenopausal women subject to osteoporosis.
Other disease processes can cause hypercalcemia but are rarely associated with elevated serum PTH levels. Widespread cancer, certain lung diseases, over ingestion of certain vitamins (A & D) can produce hypercalcemia. Rare endocrine diseases (acromegaly) as well as certain familial disorders can also be associated with hypercalcemia. Most of these diagnoses can be quickly and cost effectively ruled out by evaluating certain blood values, which include serum calcium, chloride, and phosphorous levels as well as PTH levels. A chest x-ray is also important to look for signs of additional disease. A 24-hour urinary collection to determine calcium excretion may also be ordered. A referring physician or endocrine surgeon will want to see these values to establish the diagnosis of primary hyperparathyroidism.
Many, but not all, patients with hyperparathyroidism are recommended to undergo parathyroid surgery. Indications for surgery include very high blood calcium levels, diagnosis at a young age, significant bone loss (osteoporosis), kidney stones, and abnormal kidney function. You should discuss with your medical doctor and with your surgeon if surgery or medical therapy is appropriate for you.
If you desire further information regarding hypercalcemia or parathyroid disease, we recommend reviewing the “Parathyroid Gland” portion of the American Association of Endocrine Surgeons (AAES) Patient Education Site. Patients may find that many websites offer confusing or conflicting information regarding parathyroid disorders. The AAES site offers reliable information