- Symptoms of congenital hypothyroidism
- How the diagnosis is made
- Main causes
- Treatment for congenital hypothyroidism
Congenital hypothyroidism is a metabolic disorder in which the baby's thyroid is unable to produce adequate amounts of thyroid hormones, T3 and T4, which can compromise the child's development and cause permanent neurological changes if not properly identified and treated.
The diagnosis of congenital hypothyroidism is made in the maternity ward and, if a change in the thyroid is identified, treatment is started soon afterwards through hormone replacement to avoid complications for the baby. Congenital hypothyroidism has no cure, but when the diagnosis and treatment are made early, the child is able to develop normally.
Symptoms of congenital hypothyroidism
The symptoms of congenital hypothyroidism are related to the lower levels of T3 and T4 circulating in the baby's body, which can be observed:
- Yellow skin and eyes; Muscle hypotonia, which corresponds to very flaccid muscles; Increased tongue volume; Umbilical hernia; Impaired bone development; Respiratory difficulty; Bradycardia, which corresponds to the slowest heartbeat; Anemia; Excessive drowsiness; Difficulty in feeding; Delay in the formation of the first dentition; Dry and inelastic skin; Mental retardation; Delay in neuronal and psychomotor development.
Although there are symptoms, only about 10% of babies suffering from congenital hypothyroidism have them, because the diagnosis is made in the maternity ward and hormone replacement treatment is started soon after, preventing the onset of symptoms.
How the diagnosis is made
The diagnosis of congenital hypothyroidism is made during maternity in neonatal screening tests, usually by means of the baby's foot test, in which a few drops of blood are collected from the baby's heel and sent to the laboratory for analysis.
If the heel prick test indicates congenital hypothyroidism, the measurement of the hormones T4 and TSH must be performed through a blood test for the diagnosis to be confirmed and treatment started. Other imaging tests, such as ultrasound, MRI and thyroid scintigraphy, can also be used in the diagnosis.
Main causes
Congenital hypothyroidism can be caused by several situations, the main ones being:
- Non-formation of the thyroid gland; Formation in an irregular location of the thyroid gland; Incomplete thyroid formation; Defects in the synthesis of thyroid hormones; Lesions in the pituitary or hypothalamus, which are two glands in the brain responsible for the production and regulation of hormones.
Generally, congenital hypothyroidism is permanent, however, transient congenital hypothyroidism can occur, which can be caused by insufficiency or excess of iodine from the mother or newborn or by the passage through the placenta of antithyroid drugs. Transient congenital hypothyroidism also needs treatment, but it is usually suspended at 3 years of age to perform tests that will better define the type and cause of the disease.
Treatment for congenital hypothyroidism
Treatment for congenital hypothyroidism consists of the replacement of thyroid hormones throughout life through the oral administration of a medicine, Levothyroxine sodium, which can be dissolved in a small amount of water or baby milk. When diagnosis and treatment are made late, the consequences of congenital hypothyroidism, such as mental retardation and growth retardation, may occur.
It is important that the child has his / her total and free T4 and TSH levels monitored for the pediatrician to check the response to treatment. Check out more details about the treatment of hypothyroidism in the following video:
