Hypercalcaemia

Abstract

Calcium is essential for neuromuscular activity, blood coagulation and bone health. Ninety-nine percent of calcium in the human body is stored in bones and teeth; the remaining 1% is found in the extracellular fluid bound to proteins (mainly albumin) or in the ionised (active) form. Hypercalcaemia most commonly results from endogenous hormone excess (e.g. primary hyperparathyroidism), hypercalcaemia of malignancy, exogenous hormone excess (e.g. vitamin D toxicity) or a side-effect of drug therapy (e.g. Thiazide diuretics). This article offers a systematic approach to the investigation and management of hypercalcaemia aimed at preventing long term sequalae such as osteoporosis and identifying life- threatening levels for urgent intervention.