Hypothyroidism – Congenital
Congenital Hypothyroidism is when a baby is born with low thyroid hormone levels. It can occur in several scenarios, 1) when the thyroid gland does not develop properly during the pregnancy, 2) when the thyroid is not properly producing thyroid hormone, or 3) when the mother makes antibodies that interfere with the baby’s thyroid hormone production. Congenital Hypothyroidism can be temporary or permanent. In either case, it is very important to treat the condition early because thyroid hormone is essential for normal brain development.
Symptoms of Congenital Hypothyroidism
- Usually caught early enough that there are very few symptoms
- Poor Feeding
- Umbilical Hernia
- Thick tongue, or sticking tongue out
- Poor Growth
- Poor Muscle tone, floppy baby
Evaluation of Congenital Hypothyroidism
In the United States, each state performs newborn screening that tests for congenital hypothyroidism so it can be caught by 2 weeks of age. Otherwise, blood tests are done to look at Free T4, T4 (thyroid hormone) and TSH (thyroid stimulating hormone). A thyroid scan or ultrasound may be done as well to look at the anatomy of the thyroid gland. Very rarely thyroid hormone abnormalities may be due to the lack of a signal from the pituitary gland in the brain; if this is the case, further pituitary hormones will also be screened.
Treatment of Congenital Hypothyroidism
Congenital Hypothyroidism is treated with thyroid hormone replacement as soon as this condition is suspected. It is available in a pill form that can be crushed and given with a small amount of water to the baby. When a baby is first diagnosed a Pediatric Endocrinologist will follow closely with blood tests and frequent office visits to monitor growth and development. As the child gets older the visits and lab work are less frequent.
Hypothyroidism – Acquired
Acquired hypothyroidism is typically seen in older children and is usually autoimmune, meaning the immune system attacks healthy thyroid tissue by mistake. Other common causes include damage to the thyroid gland by medication, radiation or surgery. Autoimmune hypothyroidism is the most common cause of hypothyroidism in children and is typically seen in the adolescent years and is more common in females.
Signs and Symptoms of Acquired Hypothyroidism
- Mild Weight Gain
- Dry skin and hair
- Cold Intolerance
- Slow Speech
- Puffy Face
- Poor Growth
- Swollen thyroid gland
Evaluation of Acquired Hypothyroidism
Blood tests, including free T4 (thyroid hormone) and thyroid stimulating hormone (TSH), are key to diagnosing hypothyroidism. Usually, imaging is not needed unless the physician feels a thyroid nodule or irregularity on physical examination of the thyroid gland; in these cases, a thyroid ultrasound might be performed.
Treatment of Acquired Hypothyroidism
Therapy generally consists of thyroid hormone replacement pills that can be crushed or chewed. The pills should be taken at the same time every day and should not be mixed with certain vitamins (containing iron) or soy products. Labs are usually checked every 4-6 weeks initially while adjusting the dose.
Hyperthyroidism (Excess thyroid hormone)
Hyperthyroidism is an overactive thyroid that is producing too much thyroid hormone. The excess thyroid hormone causes an increase in the body’s metabolism causing weight loss, rapid heart rate, and heat intolerance. The most common cause in children and adolescents is autoimmune also known as Grave’s Disease.
Signs and Symptoms
- Enlarged thyroid gland or goiter
- Rapid Heart Rate
- Tremor or Shakiness
- Irregular Menstrual Cycles
- Bulging Eyes
- Weight Loss
- Heat Intolerance or Sweating
Blood tests are initially drawn to check thyroid function, including thyroid hormones (Free T4, T3) and thyroid stimulating hormone (TSH). Thyroid antibodies that are seen in Grave’s Disease may also be drawn to help confirm the cause of the hyperthyroidism. If the cause is not clear your Pediatric Endocrinologist may order thyroid imaging such as an ultrasound or thyroid uptake scan for further evaluation.
Treatment includes oral antithyroid medication, such as Methimazole. Radioiodine ablation can also be used initially or if oral medication is not tolerated or effective. Thyroidectomy, which is a surgical procedure to remove the thyroid, can also be performed as therapy for hyperthyroidism. If radio ablation or surgery is performed, lifelong thyroid hormone replacement therapy will be needed.