Patients whose parathyroid activity is elevated above normal are referred to as having hyperparathyroidism. This study will help researchers better understand the causes of hyperthyroidism and to evaluate and improve methods for diagnosis and treatment.

In this study, patients diagnosed with or suspected of having hyperparathyroidism will be selected to participate. In addition, patients with related conditions such as parathyroid tumors, will also be selected.

Subjects will be asked to provide blood and urine for testing to confirm their condition. They will then be surgically treated by removal of the parathyroid gland(s) (parathyroidectomy).

Subjects with parathyroid tumors will undergo several diagnostic tests to determine the exact location of the tumor as well as the tumor's activity. The tests may include; ultrasounds, nuclear scanning, CT scans, MRI, and specialized blood testing.

Sometimes parathyroidectomy leads to hypoparathyroidism. Options for treating the patients after the surgical procedure will also be addressed. Calcium and Vitamin D supplements are typically the mainstay of post parathyroidectomy therapy. Other potential treatments include transplanting the parathyroid gland(s) to other areas of the body.

Patients with confirmed or suspected primary hyperparathyroidism or complications there from (such as postoperative hypoparathyroidism) will be admitted for diagnosis and treatment. The principal diagnostic components are calcium in serum and urine and parathyroid hormone in serum. Patients with moderately severe primary hyperparathyroidism will be treated. Treatment will be mainly by parathyroidectomy.

Preoperative testing to localize parathyroid neoplasm(s) will be used usually and with more extended methods in cases with prior neck surgery. Preoperative tumor localization tests will be selected according to clinical indications from the following: ultrasound, technetium-thallium scan, computerized tomography, magnetic resonance imaging, fine needle aspiration for parathyroid hormone assay, arteriogram, selective venous catheterization for parathyroid hormone assay. Options for management of postoperative hypocalcemia include calcium, vitamin D analogs, parathyroid autografts and synthetic parathyroid hormone. Research specimens may consist of blood or tumors.

• Hyperparathyroidism
• Hypocalcemia
• Hypoparathyroidism
• Parathyroid Neoplasm

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• Chen CC, Skarulis MC, Fraker DL, Alexander R, Marx SJ, Spiegel AM. Technetium-99m-sestamibi imaging before reoperation for primary hyperparathyroidism. J Nucl Med. 1995 Dec;36(12):2186-91.
• Pollak MR, Brown EM, Chou YH, Hebert SC, Marx SJ, Steinmann B, Levi T, Seidman CE, Seidman JG. Mutations in the human Ca(2+)-sensing receptor gene cause familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism. Cell. 1993 Dec 31;75(7):1297-303.

• INCLUSION CRITERIA:

Patients (male or female any age) with known or suspected primary hyperparathyroidism or a related disorder (such as familial multiple endocrine neoplasia type 1 [FMEN1]) will be evaluated.

The vast majority of patients will be greater than age 18.

In the rare occasion where special resources might be appropriate (uremic patient, young child), the availability of special resources would be confirmed prior to admission.

EXCLUSION CRITERIA:

There are no absolute exclusions.