Hypothyroidism

What is hypothyroidism?

Hypothyroidism is the condition in which the thyroid is underactive and is not producing enough thyroid hormone.

What causes hypothyroidism?

The most common cause of hypothyroidism is Hashimoto’s thyroiditis, which is from an autoimmune disorder that injures the thyroid and develops overtime. (The disorder is named after Doctor Hashimoto who first described it.) Other causes of hypothyroidism include certain medications, radiation exposure to the neck, some congenital syndromes, or surgery involving the thyroid gland. However, newborns can have hypothyroidism from birth which is called congenital hypothyroidism. Congenital hypothyroidism is typically caused by the thyroid not developing properly or not being able to make thyroid hormone properly. Congenital hypothyroidism can also be caused by conditions a mother may have or medications she may take during pregnancy.

What are the symptoms of hypothyroidism?

The symptoms of hypothyroidism are often vague early on, but the following are some late symptoms of the disorder. Each child may experience symptoms differently, and often the symptoms are not seen at all. This is why all newborns should be screened for hypothyroidism.

• Symptoms in newborns (neonatal hypothyroidism):
  • Jaundice (yellowing of the skin, eyes, and mucous membranes)
  • Hoarse cry
  • Poor appetite
  • Umbilical hernia (belly button protrudes out)
  • Constipation
  • Slow bone growth
• Symptoms in Childhood or Adolescence:
  • Slow growth
  • Delayed tooth development
  • Delayed puberty
  • Puffy and swollen face
  • Hair loss
  • Dry skin
  • Slow pulse
  • Cold intolerance (feeling overly cold when others are comfortable)

The symptoms of hypothyroidism may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis.

How is hypothyroidism diagnosed?

A medical history, physical examination, and measurement of thyroid hormones in the blood are needed. Blood samples may indicate hypothyroidism due to abnormal levels of T4 (a thyroid hormone ) and thyroid-stimulating hormone, or TSH (a hormone that regulates thyroid hormone production). An ultrasound or scan of the thyroid gland to check for abnormalities in the thyroid’s structure might also be done.

Treatment of hypothyroidism:

Treatment most commonly includes prescription of thyroid hormone replacement to replace the deficient hormones. The thyroid hormone given as replacement is identical to the hormone that our bodies naturally make. This thyroid hormone replacement is safe to take long-term as long as a medical provider regularly checks the T4 and TSH levels to ensure proper dosing. It is not unusual for replacement doses to go up as a child grows.

What is congenital hypothyroidism?

Congenital hypothyroidism means a low thyroid hormone disorder is present at birth. Children in the US are tested for the congenital hypothyroidism during their standard newborn screening at the time of birth. Approximately 1,400 infants per 5,000,000 newborns are diagnosed with congenital hypothyroidism shortly after birth each year. Congenital hypothyroidism can be temporary, however, brain development during the first few years of life requires normal thyroid hormone levels, so is it is important that a medical provider sees the baby to make sure thyroid hormone replacement is given if needed. Congenital hypothyroidism is typically caused by the thyroid not developing properly or not being able to make thyroid hormone properly; however, congenital hypothyroidism can also be caused by conditions a mother may have or medications she may take during pregnancy.