Hypoparathyroidism in children

Hypoparathyroidism is a deficiency of the parathyroid glands, characterized by reduced production of parathyroid hormone and impaired calcium and phosphorus metabolism.

ICD-10 code

• E20 Hypoparathyroidism.
• E20.0 Idiopathic hypoparathyroidism.
• E20.1 Pseudohypoparathyroidism.
• E20.8 Other forms of hypoparathyroidism.
• E20.9 Hypoparathyroidism, unspecified.

Causes of Hypoparathyroidism

• Postoperative hypoparathyroidism - as a result of surgical interventions on the thyroid and parathyroid glands.
• Damage to the parathyroid glands (infections, radiation exposure, amyloidosis, hemorrhage).
• Idiopathic variant (autoimmune, hypoplasia or aplasia of the parathyroid glands).
• Pseudohypoparathyroidism - Albright's syndrome, insensitivity of target organs to parathyroid hormone, combined with short stature, osteodystrophy, hyperpigmentation, soft tissue calcification, and mental retardation.

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Pathogenesis

Deficiency of parathyroid hormone leads to an increase in the blood phosphorus level (due to a decrease in the renal effect of parathyroid hormone), as well as to hypocalcemia caused by a decrease in calcium absorption in the intestine, a decrease in its mobilization from bones and insufficient calcium reabsorption in the renal tubules. In the genesis of hypocalcemia, a decrease in the synthesis of the active metabolite of vitamin D-1,25-dihydroxycholecalciferol in the kidneys is important.

Symptoms of Hypoparathyroidism in Children

Symptoms of hypoparathyroidism are caused by hypocalcemia and hyperphosphatemia, which lead to increased neuromuscular excitability and general autonomic reactivity, increased seizure readiness. Characteristic are convulsive contractions of skeletal muscles, paresthesia, fibrillary twitching of muscles, tonic convulsions, convulsive contractions of smooth muscles - laryngo- and bronchospasm, swallowing disorders, vomiting, diarrhea, constipation, mental changes (neuroses, memory loss, insomnia, depression), trophic disorders (cataracts, enamel defects, dry skin, brittle nails, impaired hair growth, early graying), autonomic disorders (fever, chills, dizziness, pain in the heart, palpitations).

Latent hypoparathyroidism occurs without visible clinical symptoms and is detected under the influence of provoking factors (infections, stress, intoxication, hypothermia).

Diagnostics

The detection of latent forms of tetany and clinical diagnosis of the disease outside of an attack can be carried out on the basis of symptoms associated with increased excitability of motor nerves.

• Chvostek's symptom is a contraction of the facial muscles when tapping at the site of the facial nerve exit on the side of the tapping.
• Weiss's symptom is a contraction of the round muscle of the eyelid and the frontal muscle when poking at the outer edge of the orbit.
• Trousseau's symptom - the appearance of cramps in the hand ("obstetrician's hand") 2-3 minutes after compression of the shoulder with a tourniquet until the pulse disappears.

It is important to remember that these tests are non-specific and do not reveal hypoparathyroidism as such, but only indicate increased seizure readiness.

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Laboratory research

Laboratory indicators of hypoparathyroidism: hypocalcemia, hyperphosphatemia, hypocalciuria, decreased serum parathyroid hormone levels, decreased urinary cAMP excretion.

Differential diagnostics

Differential diagnosis is carried out with malabsorption syndrome, epilepsy, hyperinsulinism and other convulsive conditions.

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Treatment of hypoparathyroidism in children

Treatment of acute convulsive syndrome includes intravenous infusions of calcium salts. For maintenance therapy in the interictal period, calcium salts and various vitamin D preparations are used: dihydrotachysterol, ergocalciferol. Active metabolites of vitamin D3 are used - alphacalcidol, calcitriol.