Many people have no symptoms and the condition is discovered in the course of treatment for another problem or picked up 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