Pediatric thyroid disorders

Congenital hypothyroidism

Congenital hypothyroidism (present at birth) occurs when the thyroid gland doesn’t develop or function while the baby is still in the womb. Because it may affect one baby out of every 3,000, it is something all babies are checked for during routine newborn screening.

Most have few or no symptoms because their thyroid hormone levels are just a little below normal. Infants with more severe forms often have a specific appearance that includes a dull look, puffy face and a thick protruding tongue.

The child may also have:

• Choking episodes
• Constipation
• Dry, brittle hair
• Yellow skin (jaundice)
• Lack of muscle tone
• Low hairline
• Poor feeding
• Short height
• Sleepiness

Acquired hypothyroidism (also known as Hashimoto's thyroiditis)

Acquired hypothyroidism (also known as Hashimoto's thyroiditis) is a condition often shows up in late childhood or in the teens. It is thought to be a result of the body mistaking the thyroid for an invader. The immune system then attacks the gland, as it would anything that is seen as a threat.

What are the signs and symptoms of pediatric thyroid disorders?

Symptoms are often very subtle and have a very slow onset. Thus, it may be some time before a diagnosis is made.

• An inability to exercise for the amount of time or level that they should be able to given their age (exercise intolerance)
• Constipation
• Depression
• Droopy eyelids
• Dry and thickened skin
• Dull expression on face
• Eyebrows that thin or fall out
• Fatigue
• Increased menstrual flow or cramping after puberty
• Muscle cramping
• Puffiness or swelling around the face
• Sensitivity to cold
• Slow pulse
• Slow speech
• Slowed reaction times
• Swelling at the front of neck because of an enlarged thyroid gland (goiter)
• Thinning, coarse, dry hair
• Voice that is always hoarse
• Weight gain that is not related to eating more

How are pediatric thyroid disorders diagnosed?

Blood tests are used to find out how well the thyroid is functioning. They do so by measuring thyroid stimulating hormone (TSH) or levels of specific thyroid hormones. Your child’s doctor may test for certain antibodies to the thyroid if they think the immune system might be attacking it. X-rays and other radiologic tests look at how well the thyroid is working or look for abnormalities in the gland itself.

Tests used to make a diagnosis include:

• Blood tests for circulating hormones
• Radioactive iodine uptake
• Thyroid scans
• Thyroid-stimulating hormone test
• Ultrasound 

How are pediatric thyroid disorders treated?

Medication

For most with uncomplicated hypothyroidism, hormone replacement therapy will be the only treatment required. A manmade version of T4 will be given to try and mimic normal function as closely as possible. Blood tests will be taken at intervals to make sure your child’s hormone levels are not too high or too low.

For hyperthyroidism, the treatment will depend on what is causing the extra production of hormone. For many, an antithyroid medication that blocks the thyroid’s production of hormones will be tried first.

Since there are high levels of relapse even with successful drug regimens, your child’s doctor might suggest other methods that permanently prevent hormone production. The thyroid uses iodine as a main building block for making hormones. When a child is given radioactive iodine, cells are damaged or killed. Iodine is harmless to other cells in the body, which limits side effects.

Surgery

Surgery may be considered for children with hyperthyroidism who don’t respond to medication, have bad side effects or are allergic to it, or in cases where the gland has gotten too large. It also is used when cancer has been confirmed.