Children's Hospital Colorado

Hypothyroidism in Children

What is hypothyroidism in children?

Hypothyroidism happens when the thyroid gland doesn't produce enough thyroid hormones. We call these hormones triiodothyronine (T3) and thyroxine (T4). They are important because they control the body's heart rate, temperature and metabolism. Hypothyroidism can be present at birth, which we call congenital hypothyroidism. It can also occur at a later age, which we call acquired hypothyroidism.

Pediatric hypothyroidism is a common and treatable condition that affects about one in 1,250 children. It can happen when there is a problem with the thyroid gland. This gland is located in the neck, just below the Adam's apple, and is shaped like a butterfly. We call this primary hypothyroidism. In rare cases, a problem with the pituitary gland, which is located in the brain, can cause it. The pituitary gland controls thyroid hormone production by releasing a hormone called thyroid stimulating hormone (TSH).

If left untreated, low thyroid hormone levels can cause problems, such as impaired growth and development. Other risks include anemia, which is a shortage of healthy red blood cells, and heart failure, a condition in which the heart doesn't pump as well as it should.

Types of hypothyroidism in children

  • Transient hypothyroidism happens when a baby is born with low thyroid hormone levels. It is temporary and usually stabilizes on its own or with short-term treatment. It can be due to a problem during pregnancy, such as iodine deficiency. It can also happen if the mother is taking anti-thyroid medicine or she has thyroid antibodies, which are cells in the blood that attack the thyroid gland.
  • Congenital hypothyroidism happens when a child is born producing too few thyroid hormones. This usually happens because the baby's thyroid gland is underdeveloped, or it did not develop at all. Sometimes, the baby's thyroid gland has developed, but it cannot produce enough hormones. This condition tends to run in families. It is common in newborns, though it's not always noticeable at first. That's why it is part of standard newborn screening procedures in the U.S. Treatment is important to avoid serious problems with brain development, which can lead to learning difficulties.
  • Autoimmune thyroiditis is a condition in which a child's immune system attacks and weakens the thyroid gland. This is the most common form of acquired hypothyroidism in children and teens. We also know it as Hashimoto's thyroiditis, or chronic lymphocytic thyroiditis.
  • Central hypothyroidism happens when a child's pituitary gland does not produce enough TSH. Without TSH, the thyroid gland doesn't get stimulated to produce thyroid hormones.
  • Iatrogenic hypothyroidism is caused by damage to the thyroid gland or removal of the thyroid gland. This can occur through radiation or surgery to treat thyroid cancer and other conditions.

Who gets pediatric hypothyroidism?

Autoimmune thyroiditis, the most common kind of acquired hypothyroidism in children, is more common in adolescents than young children. It is also more common in girls than boys. Children with other autoimmune disorders, such as type 1 diabetes, are at higher risk. So, we recommend that children with type 1 diabetes get regular screenings. Children with congenital syndromes, especially Down syndrome, are also at higher risk, as are children who have received cancer treatments.

Our team may also recommend screening for children with a history of radiation for cancer treatment, and those with a history of brain injury or abnormal brain development. We may also screen children with poor growth or other pediatric hypothyroidism symptoms.