Hypothyroidism in older children and adolescents
Usually the cause is autoimmune thyroiditis (Hashimoto's thyroiditis). Some symptoms of hypothyroidism are similar to those of adults (eg, weight gain, obesity, constipation, rough, dry hair, yellowish, cold or marbled rough skin). Signs specific to children include delayed physical development, late maturation of the skeleton, and usually delayed puberty. Treatment is carried out with L-thyroxine at a dose of 5-6 μg / kg orally once a day; in adolescents, the dose is reduced to 2-3 μg / kg orally once a day and titrated to maintain the level of thyroxine and thyroid-stimulating hormone in the serum at normal age limits.
Symptoms of hypothyroidism in children
Symptoms of hypothyroidism differ from those of adults. If iodine deficiency occurs early in pregnancy, the child may develop endemic cretinism (a syndrome that includes deaf mute), mental retardation and muscle spasticity. In most cases, infants with hypothyroidism have few manifestations, or they are generally absent, because the placenta receives thyroid hormones from the mother. However, after maternal hormones are metabolized, if the underlying cause of hypothyroidism is maintained, and if hypothyroidism is not diagnosed and treatment is not performed, moderate or severe retardation of the development of the central nervous system occurs, which may be accompanied by muscle hypotension, prolonged hyperbilirubinemia, umbilical hernia, respiratory failure, macroglossia, large fontanel sizes, hypotrophy and hoarse voice. Rarely, late diagnosis and treatment of severe hypothyroidism lead to mental retardation and stunting.