Clinching the diagnosis: an approach to the investigation of hypercalcemia

Hypercalcemia is a common biochemical abnormality. It is usually possible to make a presumptive diagnosis of its cause by relatively simple means. In a large majority of cases this involves differentiating between primary hyperparathyroidism and malignancy-associated hypercalcemia. Clinical evaluation and parathyroid hormone assay are particularly useful. Since the management of hypercalcemia in the short term generally involves non-specific measures such as rehydration, the inability to make an immediate accurate diagnosis presents less of a problem than might otherwise be the case. The definitive diagnosis of hyperparathyroidism, malignancy and sarcoidosis requires histological confirmation.