Hypoparathyroidism is decreased function of
the parathyroid glands with underproduction of parathyroid hormone. This can
lead to low levels of calcium in the blood, often causing cramping and
twitching of muscles or tetany (involuntary muscle contraction), and several
other symptoms. The condition can be inherited, but it is also encountered
after thyroid or parathyroid gland surgery, and it can be caused by immune
system-related damage as well as a number of rarer causes. The diagnosis is made
with blood tests, and other investigations such as genetic testing depending on
the results. The treatment of hypoparathyroidism is limited by the fact that
there is no exact form of the hormone that can be administered as replacement.
However teriparatide, brand name Forteo, a biosimilar peptide to parathyroid
hormone, may be given by injection. Calcium replacement or vitamin D can
ameliorate the symptoms but can increase the risk of kidney stones and chronic
kidney disease.
