Hipercalcemia

Résumé

The most common cause of hypercalcemia in the outpatient is primary hyperparathyroidism and it is usually caused by a parathyroid adenoma producing PTH. The malignant tumor hypercalcemia occurs in 10-20% of patients with cancer, and is the most common cause of hypercalcemia in hospitalized patients. Numerous growth factors and cytokines are involved in malignant hypercalcemia of malignancy, the most important being the PTH-related peptide (PTHrP), the ligand-receptor activator of nuclear factor kappa B (RANK-L), and transforming growth tactor-B (TGF-¡3). The determination of serum intact PTH (iPTH) reliably differentiates malignant hypercalcemia of primary hyperparathyroidism. Familial hypocalciuric hypercalcemia is a rare disorder, with which should be considered in the differential diagnosis of mild, asymptomatic hypercalcemia cases, who have hypocalciuria (CCCR < 0.02), and normal or increased PTH. Treatment of severe hypercalcemia, usually malignant, must be initiated on an urgent basis, and requires the administration of aminobisphosphonates (zoledronate) intravenously. The treatment of choice in primary hyperparathyroidism is surgical (parathyroidectomy). In selected cases, treatment may include allosteric modulators that increase the sensitivity of the calcium-sensing receptor (CaSR) to extracellular calcium (cinacalcet).