The disease may occur at any age, but most frequently affects those between 30 and 50 years old. It occurs more often in women than men. The incidence is 6 out of 100,000 people. A biopsy of the parathyroid gland shows tumor or hyperplasia . A radioimmunoassay of parathyroid hormone that shows an increased level.
Serum calcium is increased.
Serum chloride may be increased. Serum phosphorus is decreased. Serum alkaline phosphatase may be increased. Bone X-ray shows bone reabsorption or fractures . Imaging of the kidneys or ureters shows calcification or obstruction.