Parathyroid glands—there are four small (the size of a grain of rice) glands are responsible for maintaining calcium levels in the body's tissues—are found behind the thyroid gland in the neck. Since parathyroids are part of the endocrine system, we can detect disease in these glands by measuring the appropriateness of their hormone production.
Under normal conditions, a normal calcium level will be associated with a normal parathyroid hormone level. Also under normal conditions, a low serum calcium level will be associated with a high parathyroid hormone level; a high calcium level will be associated with a low parathyroid hormone level.
These are all appropriate ways in which a parathyroid gland will react to calcium that is circulating in the blood as they attempt to regulate calcium in the narrow normal range. A better explanation of the normal function of parathyroid glands is covered in more detail on our function page.
Hyperparathyroidism is relatively easy to detect because the parathyroid glands will be making an inappropriately large amount of parathyroid hormone in the face of an elevated serum calcium. This is straightforward and simple to measure.
Another way to confirm a hyperparathyroidism diagnosis is by measuring the amount of calcium in the urine over a 24-hour period. If the kidneys are functioning normally, they will filter much of this calcium in an attempt to rid the body of calcium, leading to an abnormally large amount of calcium in the urine.
Measuring calcium in the urine, however, is an indirect measure of parathyroid activity and is only accurate about 25% to 40% of the time. The most accurate and definitive way to diagnose primary hyperparathyroidism is by showing an elevated parathyroid hormone level in the face of an elevated serum calcium.
Treatment Options for Primary Hyperparathyroidism
The only 2 choices available for patients with primary hyperparathyroidism are to simply do nothing or to have the diseased parathyroid gland (or infrequently, more than one diseased parathyroid gland) surgically removed. Some physicians will elect to not refer their patients for an operation if they have a mild form of primary hyperparathyroidism.
Much of this management style stems from the fact that standard parathyroid surgery in the past required the use of general anesthesia and was a major operation. But it's important to understand that parathyroid disease will get worse. It won't go away on its own. Remember, it is caused by a tumor that has developed from one of the parathyroid glands. Waiting will just allow the parathyroid tumor to grow bigger.
Your age should also not be a reason to forego surgery. The new minimally invasive parathyroidectomy techniques have been performed on patients of many ages. The procedure uses local anesthesia that sends patients home in a matter of hours. To learn more, read our article about minimally invasive parathyroid surgery.
Can Osteoporosis Medicines be Used Instead of Operating?
Some physicians have begun using osteoporosis medications to increase bone calcium rather than referring a patient for surgery. Osteoporosis drugs are not a substitute for removal of an overactive parathyroid gland. These drugs work through a different mechanism than the over-produced parathyroid hormone.
After the offending parathyroid is removed, osteoporosis medications may play a role in building bone density and replacing the calcium that the parathyroid hormone removed. Many physicians use this strategy for their patients with documented decreases in bone density after a successful operation to remove the overactive parathyroid. However, these drugs should not be used as a substitute for addressing the actual problem at hand, which is a parathyroid gland tumor.
The bottom line is that osteoporosis medications do not work in patients with hyperparathyroidism. The bones and osteoporosis will continue to get worse. These drugs do not work in patients with parathyroid tumors until the tumor has been removed.