This tumor is the most common cause of hyperparathyroidism, which causes elevated levels of calcium in the blood (hypercalcemia). Parathyroid adenomas are generally caused by genetic mutations.

Women over 60 are at highest risk. If your head or neck has been exposed to radiation, this can also increase risk.

Many people have no symptoms. The condition is often discovered in the course of treatment for another problem or is identified via tests done as part of a general physical.

Symptoms that may occur include the following:

• lethargy
• nausea
• constipation
• myalgias (muscle pains)
• kidney stones
• bone fractures

Signs may include:

• fractures
• renal colic

Tests may show:

• elevated serum calcium
• low serum phosphorus
• elevated intact PTH
• elevated serum chloride
• low serum bicarbonate
• elevated 24-hour urine calcium
• low bone mineral density
• abnormal X-rays (may show kidney stones)
• renal stones on ultrasound or CT
• MRI or Tc-thallium neck scan showing enlarged parathyroid

Surgery is the most common treatment. However, many patients with mild hyperparathyroidism are not treated but are monitored for escalation of symptoms. Some postmenopausal women may consider estrogen replacement, which can help relieve symptoms and prevent bone loss.

Prognosis is generally good.

Complications are less common today. They include advanced renal disease such as nephrocalcinosis and osteitis fibrosa cystica (advanced bone disease). Osteoporosis and the increased risk for bone fractures associated with it is the most common concern.

Call your health care provider if you have any signs or symptoms that may be linked to this disorder.