Hypercalcaemia and primary hyperparathyroidism

Abstract

Abstract Hypercalcaemia has many potential causes, but in everyday clinical practice, primary hyperparathyroidism is the most common cause in out-patients and malignancy the most common in in-patients. Primary hyperparathyroidism affects up to 0.3% of the population, mainly older women. Although normally sporadic, a number of genetic conditions predisposing to the occurrence of primary hyperparathyroidism have been described. The most common presentation of primary hyperparathyroidism is now as an asymptomatic disorder, discovered as a chance finding during routine biochemical testing for some other indication. A large proportion of these patients can be safely managed without parathyroidectomy, by regular biochemical monitoring and periodic reassessment of bone mineral density. Evidence-based guidelines are now available from the US National Institutes of Health suggesting that parathyroidectomy should be performed in cases of primary hyperparathyroidism when the patient is less than 50 years of age, symptomatic and significantly hypercalcaemic or hypercalciuric, or has established loss of renal function or loss of bone mineral density. Operative management is traditionally a full neck exploration, but greater use of preoperative localization techniques has permitted development of day-case parathyroidectomy under local anaesthesia in some centres. In cases where surgery is not performed, bisphosphonates may be useful in the preservation of bone mineral density, and the calcimimetic agent cinacalcet is now available for medical management of hypercalcaemia caused by primary hyperparathyroidism in some countries.