A novel use of cinacalcet to distinguish primary hyperparathyroidism from hypercalcemia of malignancy in a patient with a low-normal parathyroidhormone concentration

摘要

Occasionally, patients present with hypercalcemia and a parathyroid hormone (PTH) level that is at the very low end of the PTH reference range. In this situation, differentiating primary hyperparathyroidism (PHPT) from hypercalcemia of malignancy (HCM) can be difficult. Cinacalcet induces hypocalcemia primarily through its interaction with the parathyroid cell's calcium receptor (1). Using cinacalcet as a diagnostic tool (cinacalcet suppression test), we were able to derive corroborative evidence, which helped affirm that the patient had PHPT rather than HCM.