Hyperthyroidism Symptoms & Causes


What is the thyroid gland? How does it work?

The thyroid is a small, butterfly-shaped gland in the neck that helps regulate how quickly or slowly the body uses energy. In other words, it’s key to a person’s metabolism.

The thyroid helps to regulate metabolism through the production of thyroxine, or T4. This hormone also plays an important role in the normal growth and brain development of children. Levels of T4 are in turn regulated by thyroid-stimulating hormone (TSH), which is produced in the brain. ??TSH is much like the thermostat in your home: If the T4 level is too low, TSH sends a message to the thyroid gland to make more T4, just like the thermostat activates the furnace to produce more heat if the house is too cold.

What are some of the possible complications of hyperthyroidism?
Eye problems: Graves’ ophthalmopathy is an eye condition associated with Graves’ disease. It can cause red, swollen and bulging eyes, as well as sensitivity to light and double vision.

Heart problems: A rapid heart rate, irregular heartbeat and congestive heart failure are all serious potential complications of hyperthyroidism. Fortunately, these complications can be avoided with prompt and adequate treatment.

Osteoporosis: Hyperthyroidism can lead to thinning or brittle bones, or osteoporosis. This is because excess thyroid hormone prevents the body from using calcium, a bone-strengthening mineral.

Skin problems: Graves’ dermopathy is a rare condition in which the skin, often on the child’s shins and feet, becomes red and swollen.

Thyrotoxic crisis (“thyroid storm”): This is a sudden onslaught of symptoms such as rapid heart rate and fever. If you think your child is experiencing a thyrotoxic crisis, you should always seek immediate medical care.

What causes the bulging eyes that are frequently associated with hyperthyroidism?
In Graves’ disease, the antibodies that stimulate the thyroid gland can sometimes interact with tissues behind the eye, leading to swelling and causing the bulging-eyed appearance some people with hyperthyroidism have.

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What causes hyperthyroidism?
There are several possible causes for the condition:

Graves’ disease: The most common cause of hyperthyroidism in children and adolescents is Graves’ disease. This is an autoimmune disorder in which the body produces antibodies that stimulate the thyroid gland to produce more and more thyroid hormone.

Neonatal Graves’ disease: In newborns, the most common cause of hyperthyroidism is neonatal Graves’ disease. This happens after the mother passes the thyroid-stimulating antibodies to her child, causing the baby to have a temporary case of hyperthyroidism (or until the antibodies are cleared from the baby’s circulation).

Thyroid nodules: Rare in children, thyroid nodules are growths in the thyroid gland that are usually benign, meaning they do not cause cancer. Sometimes, these growths produce thyroid hormones that can lead to hyperthyroidism.

Thyroiditis: Sometimes, the thyroid gland can become inflamed, which can lead to excess thyroid hormone leaking into the blood. This condition is known as thyroiditis and is rare in children.

Signs and symptoms

How can I tell if my child might have an overactive thyroid?

The most common signs and symptoms of hyperthyroidism are:

  • difficulty gaining weight
  • fast or irregular heartbeat
  • high blood pressure
  • nervousness and trouble concentrating
  • irritability
  • bulging eyes
  • diarrhea
  • poor school performance
  • infants may have trouble breathing (caused by an enlarged thyroid gland pressing on the windpipe)
Giving thanks to a special Endocrinology nurse
Linda Darling thanks Virginia Rich, RN, from Children’s Endocrinology Division for having a "positive impact" in her son’s life. Read her letter

Questions to ask your doctor

You and your family play an essential role in your child’s treatment for hyperthyroidism. It’s important that you share your observations and ideas with your child’s treating physician, and that you have all the information you need to fully understand the treatment team’s explanations and recommendations.

You’ve probably thought of many questions to ask about your child’s condition and prognosis. It’s often very helpful to jot down your thoughts and questions ahead of time and bring them with you, along with a notebook, to your child’s appointment. That way, you will have all of your questions in front of you when you meet with your child’s treating clinician and can make notes to take home with you. (If your child is old enough, you can encourage him or her to write down questions, too.)? ?Initial questions to ask your doctor might include:

  • How did you arrive at this diagnosis?
  • Are there any other conditions my child might have instead of hyperthyroidism?
  • What do you think caused my child’s hyperthyroidism?
  • Does he have any other disorders or complications?
  • How should I talk to my child about her condition?
  • How should I explain my child’s hyperthyroidism to others?
  • Do I need to make any other changes to my child’s home and school routines?
  • What other resources can you point me to for more information?
  • What treatment approach do you feel is best for my child, and why?
  • Does my child need medication? If so, what are the possible side effects?
  • Will my child need to have surgery?
  • What precautions do I need to take as far as my child’s diet and exercise?
  • How can I help my child be more comfortable?
  • If my child is struggling with his illness, should he talk to a therapist?
Did you know?
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Q: Could I have done something to prevent my child’s hyperthyroidism?

?A: No. If your child has Graves’ disease—as many children with hyperthyroidism do—there was no way to prevent his thyroid from becoming overactive. Graves’ disease is caused by a malfunction in a child’s immune system. While there is a genetic component to the condition, no individual gene triggers Graves’ disease. Experts believe a combination of genetics and environmental factors are responsible.
The other common causes of hyperthyroidism—thyroid nodules and thyroiditis—are also not preventable.

Q: What is “thyroid storm," and how do I look out for it in my child’s case?

?A: "Thyroid storm," or thyrotoxic crisis, is a very serious complication of hyperthyroidism. It occurs when a child’s thyroid hormone levels become severely elevated. Though thyroid storm is rare, when it does occur, it can be life-threatening. The most important symptom to look out for is a very high temperature (up to 105 or 106 degrees Fahrenheit). If you suspect your child may be experiencing thyroid storm, you should always seek immediate medical care.

Q: If I have another child, is he or she at risk of developing hyperthyroidism too??

A: The answer depends on your child’s specific type of hyperthyroidism. If he has an overactive thyroid caused by a nodule or thyroiditis, it is unlikely other members of his family—including siblings—will have hyperthyroidism. However, if he has been diagnosed with Graves’ disease—the most common cause of childhood hyperthyroidism—there is a possible genetic link.
Graves’ disease is a genetic autoimmune disorder, meaning that genes play a role in the onset of the disease (although there is no one gene that has been identified as the culprit). If your child has been diagnosed with Graves’ disease, you and other members of your family should have your thyroid levels checked as a precaution.??

Q: Can dietary changes make a difference for my child??

A: No dietary regimen can prevent or cure hyperthyroidism. However, it’s important for your child to follow a healthy and nutrient-rich diet that does not contain excessive amounts of iodine. Since hyperthyroidism can cause unwanted weight loss if not properly treated, always make sure your child is taking in enough healthy calories (the weight loss should stop once the hyperthyroidism is being treated).
If your child has also been diagnosed with celiac disease, you should carefully adhere to your doctor’s recommendations for a gluten-free diet.

Q: Does my child need to cut back on sports or other physical activities?

?A: If your child’s hyperthyroidism is not properly under control, she might experience rapid heart rate or fatigue. Any time she has these symptoms, you should contact your doctor right away. ??Another possible complication of hyperthyroidism is osteoporosis, which leads to brittle bones that are more susceptible to breaks and bruises. For all of these reasons, always ask your child’s doctor for recommendations and guidelines about taking part in sports and play.
Once her hyperthyroidism is being managed, and if there are no other complications, your child will most likely be able to resume her normal physical activities just like any other kid her age.

Q: Will hyperthyroidism affect my child’s appearance or mood?

?A: Before your child’s hyperthyroidism is diagnosed and being managed, he may appear underweight or “peaked.” Other physical symptoms can include bulging eyes or Graves’ dermopathy, the development of red, swollen skin (most often on the shins and feet). Because an overactive thyroid increases metabolism to an excessive level, your child may also feel (and act) anxious, restless and irritable. If these symptoms do not clear up with treatment, you should ask your doctor whether your child might benefit from talking to a therapist or other behavioral health professional.

Q: Will my child still enjoy a good quality of life?

A: Yes. The good news is that, with the right diagnosis and management, hyperthyroidism is a very treatable disease, and your child can go on to live a full, active and enjoyable life.

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