Hypoparathyroidism is a rare endocrine disorder characterized by low calcium and high phosphate levels, in the setting of a low or inappropriately normal PTH level. Given its rarity, it has been classified as an orphan disease in the United States and by the European Commission. The first international conference on the management of hypoparathyroidism was convened in Florence Italy 2015 and resulted in the publication of detailed guidelines on the epidemiology, presentation, clinical features and management of hypoparathyroidism. Hypoparathyroidism may be associated with a spectrum of clinical manifestations, ranging from asymptomatic in the setting of mild hypocalcemia, to life threatening cardiac arrythmias, seizures or laryngospasm, in the setting of severe acute hypocalcemia. The most common cause is postsurgical hypoparathyroidism following anterior neck surgery, followed by autoimmune disorders and rarely genetic disorders. Establishing a diagnosis of hypoparathyroidism is important as it is associated with the development of kidney stones, renal insufficiency, cataracts, basal ganglia calcifications, as well as a reduced health-related quality of life.
Most patients with chronic hypoparathyroidism require lifelong high dose calcium and activated vitamin D supplements. The goals of treatment are 3 fold, namely, relieve symptoms of hypocalcemia, raise calcium concentration to the low-normal range and avoid hypercalciuria. For those individuals who cannot maintain a stable serum and urine calcium with conventional calcium and activated Vitamin D regimens, the addition of recombinant PTH (1-84) is currently an option. The approval of recombinant PTH (1-84) represents a significant step forward in the management of this disorder.
Bridget P Sinnott