Severe Symptomatic Hypercalcemia in a Patient With Familial Hypocalciuric Hypercalcemia

One of the less common causes of hypercalcemia is familial hypocalciuric hypercalcemia (FHH). It is an autosomal-dominant genetic condition, which presents asymptomatically in most patients while some may have mild symptoms. The serum calcium levels are mildly elevated with mild elevation in parathyroid hormone, which rarely requires management with pharmacologic agents. We present an unusual case report of a 76-year-old woman, confirmed to have FHH type 1 mutation, presented with symptomatic hypercalcemia probably set off by metabolic stresses of her age and needing intensive treatment with intravenous bisphosphonates, calcitonin and cinacalcet.