Cinacalcet to prevent parathyrotoxic crises in hypercalcaemic patients awaiting parathyroidectomy

Primary hyperparathyroidism is the third most common endocrine disorder. Hypercalcaemia exceeding 3 mmol/l is a major risk factor for parathyrotoxic crises, and management of patients at risk remains a medical challenge. The authors recently managed three such patients referred for severe nephrolithiasis. All had severe hypercalcaemia (at least 3 mmol/l). Instead of the usual management, which involves hospitalisation in an intensive care environment (for about 5-7 days) for rehydration and infusion of intravenous bisphosphonates, followed by emergency parathyroidectomy, the three patients received ambulatory cinacalcet (not an approved indication), 30 mg twice a day. The serum calcium normalised in two cases and declined to a safe level in the third case, allowing minimally invasive parathyroidectomy to be performed at a date chosen according to the patients' and surgeon's respective schedules. The authors consider that cinacalcet may benefit severely hypercalcaemic patients awaiting surgery for primary hyperparathyroidism.