[Hypo and hypercalcemia: from diagnosis to treatment]

The hypercalcemia is defined as a blood calcium range above 2.6 mmol/l. Its prevalence is variable in different studies and it is comprised between 2 and 8/1000 in the general population. The primary hyperparathyroidism (PHP) and cancers are both responsible for about 80 per cent to 90 per cent of causes of hypercalcemia1. The PHP is the first ambulatory cause of hypercalcemia. Contrarily to this, the neoplastic etiology is mainly seen in the hospital settings. The other causes of the hypercalcemia are vitamin D overdose, secondary hypercalcemia due to medications intake and familial hypocalciuric hypercalcemia which will be discussed in this article. The hypocalcemia is defined as a blood calcium range underneath 2.2 mmol/l. The most common etiologies are the postoperative hypopara-thyroidism as a complication of approximatively 1.5 % of thyroidectomies2, the vitamin D deficiency and terminal chronic kidney failure. The other rare causes such as autoimmune hypoparathyroidism, parathyroid agenesis, pseudoparathyroidism and hypomagnesemia will be discussed in this article.