Hypoparathyroidism describes a condition in which there are low circulating levels of parathyroid hormone (PTH) or insensitivity to its action.
The causes of hypoparathyroidism vary; however, they all share a common feature of hypocalcemia. The presentation of hypoparathyroidism also varies depending on the chronicity of the resultant hypocalcemia. Muscle spasms/tetany, paresthesias, and seizures may occur in an acute onset, whereas chronic hypoparathyroidism may only be evidenced by visual impairment due to cataract formation.
See Hypocalcemia for more information.