Some symptoms of elevated parathyroid levels include bones that are weak and easily break, pain in the bones and joints, frequent urination, pain in the abdomen, and depression, according to Mayo Clinic. Other symptoms are kidney stones, loss of appetite, nausea and vomiting. Patients may also be forgetful and complain of sicknesses that have no obvious cause.
These symptoms come fairly late during the course of hyperparathyroidism, Mayo Clinic explains. By the time they appear, the patient's organs have been damaged from hypercalcemia in his urine and blood and hypocalcemia in his bones. Also, the symptoms are so nonspecific that they may be indications of more serious diseases.
Hyperparathyroidism can be primary or secondary, advises Mayo Clinic. Primary hyperparathyroidism is caused when something goes wrong with the parathyroid glands. Usually there is a benign growth on the gland, but in other cases, at least two of the four paraythroid glands are enlarged. A cancerous tumor can also cause problems, though cancer of the parathyroid glands is rare. Often, no one knows why a person has elevated parathyroid levels, but in some patients the cause is genetic.
Secondary hyperparathyroidism is a complication of another condition that causes calcium deficiency, Mayo Clinic reports. Because of this, the parathyroid glands, which balance the levels of calcium and phosphorus, work too hard and grow exhausted. Causes of secondary hyperparathyroidism are chronic kidney disease and severe deficiencies in vitamin D and calcium.