Hypoparathyroidism: an overview of information
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Hypoparathyroidism, or deficiency of parathyroid glands, is a disease associated with a change in the secretion of parathyroid hormone, characterized by pronounced disturbances in the phosphorus-calcium metabolism.
The cause and pathogenesis of hypoparathyroidism. It is possible to single out the following basic etiological forms of hypoparathyroidism (in decreasing order of frequency): postoperative; associated with radiation, vascular, infectious lesions of the parathyroid glands; idiopathic (with congenital underdevelopment, absence of parathyroid glands or autoimmune genesis).
The most common cause of hypoparathyroidism is the removal or damage of the parathyroid glands (one or several) during imperfect operations on the thyroid gland, which is associated with their anatomical proximity, and in some cases - with an unusual arrangement of glands. It is important their trauma during surgery, violation of innervation and blood supply of the parathyroid glands. The incidence of the disease after surgery on the thyroid gland varies, according to different authors, from 0.2 to 5.8%.
[Symptoms of hypoparathyroidism
Patients with hypoparathyroidism are concerned about paresthesia, cold snap and a feeling of creeping crawling all over the body, especially in the limbs, convulsive twitching in the muscles, bouts of painful tonic convulsions, nervousness. In the late stages of the disease there are skin changes, cataracts, calcifications in various organs and in the subcutaneous tissue.
In the course and nature of the clinical features of hypoparathyroidism, two of its forms are distinguished: manifest (manifest), with acute and chronic manifestations, and latent (latent).
Clinical symptoms of hypoparathyroidism are composed of several groups of symptoms: increased neuromuscular conduction and convulsive readiness, visceral-vegetative and neuropsychic disorders.
What do need to examine?
How to examine?
Diagnosis and differential diagnosis of hypoparathyroidism
Diagnosis of manifest forms of hypoparathyroidism is not difficult. It is based on anamnesis data (surgery on the thyroid or parathyroid gland, treatment 131 1); the presence of increased neuromuscular excitability with attacks of tonic convulsions or readiness for convulsions; presence of hypocalcemia and hypocalciuria; hyperphosphatemia and hypophosphaturia; decreased serum parathyroid hormone levels; on a decrease in the excretion of cAMP in the urine, which reaches its normal value after the administration of parathyroid hormone preparations; on the presence of an extension of the intervals QT and ST on the ECG; in later stages of the disease - on the presence of cataracts and other manifestations of calcification of tissues; on the changes of ectodermal derivatives - skin, hair, nails, enamel of teeth.
With hypoparathyroidism, the total blood calcium content decreases below 2.25 mmol / l, at a level of less than 4.75 mmol / l, calcium ceases to be detected in the urine (in Sulkovich's sample). Hyperparathyroid crises occur at a serum calcium level of less than 1.9-2 mmol / L, and ionized - less than 1-1.1 mmol / l.
Treatment of hypoparathyroidism
It is necessary to distinguish its features in the period of acute tetanus attack and emphasize the need for supporting systematic therapy in the interictal period. To treat the hypoparathyroid crisis intravenously, 10% calcium chloride or calcium gluconate solution is administered. The dose is determined by the severity of the attack and ranges from 10 to 50 ml (usually 10-20 ml). The effect should occur at the end of the infusion. In connection with the possibility of intoxication (danger of collapse, ventricular fibrillation of the heart), the drug should be administered slowly. Since calcium is excreted from the body for 6-8 hours, it is advisable to repeat the injection 2-3 times a day. During the interictal period, his drugs (gluconate, lactate, chloride) are administered orally in a dose of 1-2 g / day after meals.
In case of crisis, also parathyroidine is used - an extract of parathyroid glands of cattle at a dose of 40-100 ED (2-5 ml) intramuscularly. The effect occurs after 2-3 hours and lasts a day with a maximum of action after 18 hours. Parathyroidin for maintenance therapy is used limitedly because of the possibility of developing resistance and the occurrence of allergies. If necessary, conduct treatment courses for 1.5-2 months with interruptions for 3-6 months.