hypoparathyroidism

Hypoparathyroidism results from reduced secretion of parathyroid hormone by the parathyroid glands. It results in hypocalcemia.

Epidemiology

Hypoparathyroidism has an estimated prevalance 37 per 100,000 person-years and incidence of 0.8 per 100 000 person-years. It carries no increased risk of mortality. The majority of cases are due to complications from anterior neck surgery.

Clinical presentation

  • tetany: peripheral paresthaesia, carpopedal spasm, seizures
  • emotional lability, depression and anxiety, psychosis
  • short stature

Pathology

There are a number of causes of hypoparathyroidism :

  • iatrogenic, e.g. post parathyroidectomy or thyroidectomy
  • congenital absence of the parathyroid glands, which may be syndromic in thymic aplasia, or 22q11.2 deletion syndrome (a.k.a. DiGeorge syndrome)
  • familial, e.g. autoimmune polyendocrine syndrome type 1
  • idiopathic (probably autoimmune-mediated destruction)
Markers
  • parathyroid hormone (PTH) level: low
  • serum phosphate level: high
  • serum calcium level: low  

Radiographic features

Differential diagnosis