Diagnosis
In most cases, elevated calcium is found by blood tests ordered for other reasons. For example, routine blood work or testing to figure out the cause of symptoms of another condition. Your provider may diagnose hyperparathyroidism by ordering:
- Blood tests
- If blood test results show that you have high calcium levels in your blood, your health care provider will likely repeat the test. This repeated test can confirm the results after you haven't eaten for a period of time.
- Many conditions can raise calcium levels. But your health care provider can diagnose hyperparathyroidism if blood tests show you also have high levels of parathyroid hormone.
- Additional tests
- After diagnosing primary hyperparathyroidism, your health care provider will likely order more tests. These can rule out possible conditions causing hyperparathyroidism, identify possible complications and determine the severity of the condition. These tests include:
- Bone mineral density test. This test is done to see if you have developed osteoporosis. The most common test to measure bone mineral density is dual-energy X-ray absorptiometry (DEXA).
- This test uses special X-ray devices to measure how many grams of calcium and other bone minerals are packed into a bone segment.
- Urine test. A 24-hour collection of urine can provide information on how well your kidneys work and how much calcium is passed in your urine.
- This test may help your provider determine the severity of hyperparathyroidism or diagnose a kidney disorder causing hyperparathyroidism. If a very low calcium level is found in the urine, this may mean it's a condition that doesn't need treatment.
- Imaging tests of kidneys. Your provider may order an X-ray or other imaging tests of your abdomen to determine if you have kidney stones or other kidney problems.
- Imaging tests before surgery
- If your health care provider recommends surgery, one of these imaging tests may be used to locate the parathyroid gland or glands that are causing problems:
- Sestamibi parathyroid scan. Sestamibi is a radioactive compound that is absorbed by overactive parathyroid glands. It can be detected by a scanner that detects radioactivity.
- A healthy thyroid gland also absorbs sestamibi. To keep the thyroid absorption from blocking the view of the absorption in a parathyroid tumor (adenoma), you're also given radioactive iodine. This is only absorbed by the thyroid. Using this process, the thyroid image is digitally removed so it can't be seen.
- Computerized tomography (CT) scanning may be combined with the sestamibi scan to improve detection of any problems with the parathyroid glands.
- Ultrasound. Ultrasound uses sound waves to create images of your parathyroid glands and surrounding tissue.
- A small device held against your skin (transducer) sends out high-pitched sound waves and records the sound wave echoes as they reflect off internal structures. A computer converts the echoes into images on a monitor.
