Patients with a history of nephrolithiasis or a suspected metabolic bone disease are increasingly being identified with elevated PTH concentrations in the setting of consistently normal serum and ionized calcium concentrations.
A diagnostic label of normocalcaemic hyperparathyroidism (NPHPT) has been given to this phenotype and in most such individuals, the initial PTH measurement is driven by the presence of metabolic bone disease.
To report the case of a man who presented with profoundly elevated parathyroid hormone levels in the setting of hypercalcemia, a palpable neck mass, renal disease, and metabolic bone disease.
A certain range of physiological doses of 1alpha,25(OH)(2)D(3) rather suppress the PTH-induced bone resorption in vivo, supporting the concept that 1alpha,25(OH)(2)D(3) or its derivatives are useful for the treatment of various metabolic bone diseases such as osteoporosis and secondary hyperparathyroidism.