Blood tests should l be done to check for increased levels of parathyroid hormone (PTH), calcium, and alkaline phosphatase, and lower levels of phosphorous. A 24-hour urine collection test can help determine how much calcium is being removed from the body

The parathyroid glands are located in the neck, near or attached to the back side of the thyroid gland. They produce parathyroid hormone. This hormone controls calcium, phosphorus, and vitamin D levels in the blood and bone.

When calcium levels are too low, the body responds by making more parathyroid hormone. This hormone causes calcium levels in the blood to rise, as more calcium is taken from the bone and reabsorbed by the intestines and kidney.

One or more of the parathyroid glands may grow larger. This leads to too much parathyroid hormone (a condition called primary hyperparathyroidism). Most often, the cause is not known. When a parathyroid gland is diseased, it causes calcium to be leached from the bones

The disease is most common in people over age 60, but it does also occur in younger adults. .
Women are more likely to be affected than men.
Radiation to the head and neck increases the risk.