<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A condition in which the parathyroid gland (one of four pea-sized organs found on the thyroid) makes too much parathyroid hormone. This causes a loss of calcium from the bones and an increased level of calcium in the blood. Symptoms include bone pain and kidney problems.</n0:def-definition><n0:def-source>NCI-GLOSS</n0:def-source></n0:ComplexDefinition><n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A disorder characterized by an increase in production of parathyroid hormone by the parathyroid glands. This results in hypercalcemia (abnormally high levels of calcium in the blood).</n0:def-definition><n0:def-source>CTCAE</n0:def-source></n0:ComplexDefinition>
<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>Hyperfunction of the parathyroid glands resulting in the overproduction of parathyroid hormone. It may be primary or secondary; primary hyperparathyroidism is caused by parathyroid adenoma, parathyroid hyperplasia, parathyroid carcinoma, and multiple endocrine neoplasia. It is associated with hypercalcemia and hypophosphatemia. Signs and symptoms include weakness, fatigue, nausea, vomiting, constipation, depression, bone pain, osteoporosis, cystic bone lesions, and kidney stones. Secondary hyperparathyroidism is caused by the chronic stimulation of the parathyroid glands in patients with chronic renal failure, rickets, and malabsorption syndromes.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>