Hyperthyroidism (Graves Disease)

What is hyperthyroidism?

Hyperthyroidism means overactivity of the thyroid gland, resulting in too much thyroid hormone in the bloodstream. The over-secretion of thyroid hormones leads to overactivity of the body's metabolism. In newborns, the most common cause of an overactive thyroid is called neonatal Graves disease, which can be life threatening. However, hyperthyroidism rarely occurs in children and adolescents.

What causes hyperthyroidism?

In newborns, the cause of hyperthyroidism (also called Graves disease) is a mother who has or has had Graves disease herself. Graves disease in adults is an autoimmune disorder characterized by the production of antibodies that stimulate the thyroid gland. When a pregnant woman has these antibodies, they can cross the placenta and affect the fetus' thyroid gland. Graves disease in pregnant woman can result in stillbirth, miscarriage, or premature birth.

What are the symptoms of hyperthyroidism?

The following are the most common symptoms of hyperthyroidism in a newborn. However, each baby may experience symptoms differently. Symptoms may include:

• poor weight gain
• fast heartbeat (which can lead to heart failure)
• high blood pressure
• nervousness
• irritability
• bulging eyes
• vomiting
• diarrhea
• difficulty breathing due to enlarged thyroid gland (goiter) pressing on windpipe

Prolonged exposure to high levels of the thyroid-stimulating antibodies characteristic of hyperthyroidism can pose serious health problems to an infant later in childhood, including the following:

• premature closing of bones in the skull (fontanelles)
• mental retardation
• hyperactivity
• slowed growth

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

How is hyperthyroidism diagnosed?

If not diagnosed shortly after birth, hyperthyroidism in the newborn can be fatal. In addition to a complete medical history and physical examination, diagnostic procedures for hyperthyroidism may include measurement of thyroid hormone in the bloodstream.

Treatment for hyperthyroidism:

With prompt treatment, babies usually recover completely within a few weeks. However, hyperthyroidism may recur during the first 6 months to 1 year of life. The goal of treatment is to restore the thyroid gland to normal function, producing normal levels of thyroid hormone. Specific treatment for hypothyroidism will be determined by your child's physician based on:

• your child's age, overall health, and medical history
• extent of the disease
• your child's tolerance for specific medications, procedures, or therapies
• expectations for the course of the disease
• your opinion or preference

Treatment may include:

• medication that blocks the production of thyroid hormones
• treatment for heart failure