Hypoparathyroidism in children

Hypoparathyroidism - deficiency of parathyroid gland function, characterized by decreased production of parathyroid hormone and a violation of 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 of parathyroid glands (infections, radiation exposure, amyloidosis, hemorrhage).
• Idiopathic variant (autoimmune, hypoplasia or aplasia of parathyroid glands).
• Pseudohypoparathyroidism - Albright syndrome, insensitivity of target organs to parathyroid hormone, is combined with short stature, osteodystrophy, hyperpigmentation, calcification of soft tissues, lagging behind in mental development.

[1], [2], [3], [4], [5], [6]

Pathogenesis

Lack of parathyroid hormone leads to an increase in the level of phosphorus in the blood (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 the bones, and an inadequate reabsorption of calcium in the renal tubules. In the genesis of hypocalcemia, the reduction in the synthesis in the kidneys of the active metabolite of vitamin D-1,25-dihydroxycholecalciferol is important.

Symptoms of hypoparathyroidism in children

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

Latent hypoparathyroidism proceeds without visible clinical symptoms and is detected by the action of provoking factors (infection, stress, intoxication, hypothermia).

Diagnostics

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

• The symptom of the tail is the contraction of the facial muscles when tapping at the point of exit of the facial nerve on the side of effleurage.
• The symptom of Weiss is the contraction of the round muscle of the eyelids and the frontal muscle when pawing at the outer edge of the orbit.
• The symptom of Trusso is the appearance of seizures in the hand ("hand of an obstetrician") 2-3 minutes after the shoulder is compressed by a tourniquet until the pulse disappears.

It must be remembered that these samples are non-specific and reveal not hypoparathyroidism as such, but merely indicate an increased convulsive readiness.

[7], [8], [9], [10], [11]

Laboratory research

Laboratory indices of hypoparathyroidism: hypocalcemia, hyperphosphataemia, hypocalciuria, reduction of parathyroid hormone content in the blood serum, reduction of cAMP excretion in urine.

Differential diagnostics

Differential diagnosis is carried out with a syndrome of impaired absorption, epilepsy, hyperinsulinism and other convulsive conditions.

[12], [13], [14], [15], [16]

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 preparations of vitamin D are used: dihydrotachysterol, ergocalciferol. Active metabolites of vitamin D3 - alfacalcidol, calcitriol are used.