Parathyroid glands control the way that your body uses calcium. They function like a thermostat to control the level of calcium in the bloodstream, by increasing or decreasing the production of parathyroid hormone (PTH).
What is Hyperparathyroidism?
The parathyroid glands sit behind the larger thyroid gland near the front of the neck and beside the trachea (windpipe). There are four glands; two in the upper or superior position on either side of the trachea, and two in the lower positions. When one or more of these glands becomes overactive and produces too much PTH, the condition is called hyperparathyroidism. Usually, this is first noticed when a patient has a high calcium level on routine blood tests. Over time, problems can arise such as loss of bone density (osteoporosis), fatigue, and kidney stones. About 1% or 1 in 100 people will develop this disease over the course of their lifetime and require surgery to treat it. Anyone can develop hyperparathyroidism at any age. However, it is more common in women than in men and more common in older adults than in younger people.
Causes of Hyperparathyroidism
The most common cause of hyperparathyroidism is an overgrowth of one or more of these glands that become overactive and produce too much PTH. This enlarged gland is referred to as an adenoma. Usually only one is present (~85% of the time) but more than one or all of the glands may be affected. As these abnormal glands enlarge, they produce PTH in excess of what the body needs, causing calcium to rise, and a host of other problems. This is referred to as Primary Hyperparathyroidism.
Other disease processes and medications can alter calcium metabolism in a harmful way; such as Kidney disease, certain diuretics, and Vitamin D deficiency. Any of these conditions might cause PTH to rise in response. This is known as Secondary Hyperparathyroidism, and usually does not require surgery.
When kidney failure is long lasting, this can lead to permanent enlargement of all of the parathyroid glands as the body tries to balance out the excess phosphate associated with end-stage kidney disease. This is known as Tertiary Hyperparathyroidism, and often requires surgery to remove most of the permanently enlarged parathyroid glands. Another term for this enlargement is parathyroid hyperplasia, meaning that all 4 of the parathyroid glands are enlarged and overactive. Parathyroid hyperplasia can run in families, and usually needs surgery when it develops.
Symptoms of Hyperparathyroidism
Hyperparathyroidism can cause a number of symptoms and worsen some underlying illnesses already present. These can include:
- Osteoporosis - or loss of bone density leading to fractures
- Kidney Stones
- Memory loss or forgetfulness
- GERD - acid reflux disease
- Poor ability to concentrate
- Bone pain
For patients with hyperparathyroidism, the excess PTH in the bloodstream causes calcium levels to rise and bone density to fall. Given enough time, everyone with this disease will experience bone loss and osteoporosis putting them at risk for painful and potentially life-threatening hip, spine, and other bone fractures. The high calcium levels also directly affect cellular metabolism, causing the other symptoms and problems above. Rarely if hyperparathyroidism goes far out of control, then dangerously high calcium levels can develop requiring hospitalization and urgent treatment for problems such as coma. All of the symptoms listed above can be serious, and life-impairing.
Hyperparathyroidism is straightforward to diagnose. An elevated serum calcium is usually the first sign of trouble. Then a measurement of PTH and Vitamin D levels can confirm the diagnosis. A patient’s entire medical history should be considered, as medications and other diseases can affect calcium and PTH. A 24 hr urine collection to test for calcium levels is helpful to screen out other medical causes for high calcium levels. After a diagnosis of Primary Hyperparathyroidism is made with blood and urine tests, imaging studies including neck ultrasound and parathyroid lymphoscintigraphy (parathyroid scanning) can help determine the number and location of abnormal glands in preparation for surgery.
Hyperparathyroidism almost always requires surgery to be cured. The purpose of surgery is to remove the diseased gland or glands and leave the normal ones in place. Then the normal glands can resume their job of correctly regulating calcium. Usually, this surgery can be done through a small minimally invasive incision in front lower part of the neck. The surgeon can find and remove one or more diseased glands through this small incision. A preoperative parathyroid scan and ultrasound can assist in identifying the location of the diseased glands, and their amount of PTH production. The surgery is typically brief, and most patients can have it performed as an outpatient, returning home the same day.
Once the diseased glands are removed, the remaining glands will soon begin to function normally to regulate calcium. This won’t happen immediately, so patients are asked to take a calcium supplement by mouth for a few days. Depending on the amount of underlying bone loss, it may be a good idea to remain on extra calcium and other medicines for some time to help rebuild lost bone density. Your doctor will advise you on this, and when to have bone density rechecked.
Other symptoms of high blood calcium levels and hyperparathyroidism are frequently relieved soon after surgery. Some patients note improved energy and concentration the next day. Usually, all patients will notice an improvement in symptoms within a few days.
Successful parathyroid surgery is almost always life changing in a positive sense, restoring a patient back to normal life. When performed by an experienced surgeon, the procedure is safe, brief, and effective.