Thyroid Issues in Kids

While you might think that the thyroid, a gland in the neck, has more impact on adults, it has particular importance in children as well. The thyroid’s hormone, levothyroxine (LEE voe thye ROX een), keeps the body functioning at the right speed. Normal thyroid function is important for growth and brain development. The latter is particularly important in newborns.

About one in 3000 babies is born with an underactive thyroid. All babies are tested via blood sampling shortly after birth for this condition, known as congenital hypothyroidism. Prior to screening, this condition was a major cause of developmental delay. When screening results in early replacement of thyroid hormone, these babies lead healthy lives.

Under (hypothyroidism) and over (hyperthyroidism) active thyroid disease can occur at any time in children and adults. An underactive thyroid is more common. Symptoms of underactive thyroid disease are decreased energy, feeling cold, constipation, and slow growth. While weight gain does occur in hypothyroidism it is rarely a cause of obesity in children, unless growth is slow as well. Obesity itself causes mild abnormalities of the thyroid function tests; these changes are not the cause of obesity. Hypothyroidism is easily treated with levothyroxine replacement and monitoring thyroid function tests.

Symptoms of overactive thyroid disease are increased agitation and anxiety, decreased exercise tolerance, rapid heart rate, feeling hot all the time, and diarrhea. Treatment of hyperthyroidism is more complicated. Medical, radiological, and surgical treatments are available.

If the thyroid function tests are abnormal or the thyroid is felt to be enlarged on physical exam, a thyroid ultrasound is frequently done. Small nodules (bumps in the thyroid gland) or cysts (fluid collections in the thyroid gland) that are less than one centimeter (3/8 inch) in size on these ultrasounds are common and usually not a cause for concern. Thyroid cancer is a possibility when larger nodules are found, but most thyroid nodules are still benign. Arrangements may be made for some nodules to get a sample using a very thin needle to determine what, if any, further treatment is needed.

Almost all thyroid cancers have excellent survival with surgery and treatment with radioactive iodine.