Serum total calcium level > 12 mg per dL (3 mmol per L) at any time
Hyperparathyroid crisis (discrete episode of life-threatening hypercalcemia)
Marked hypercalciuria (urinary calcium excretion more than 400 mg per day)
Nephrolithiasis
Impaired renal function
Osteitis fibrosa cystica
Reduced cortical bone density (measure with dual x-ray absorptiometry or similar technique)
	Bone mass more than two standard deviations below age-matched controls (Z score less than 2)
Classic neuromuscular symptoms
	Proximal muscle weakness and atrophy, hyperreflexia, and gait disturbance
Age younger than 50