The thyroid is a small, butterfly-shaped gland located at the base of the neck just below the Adam's apple. It’s part of an intricate network of glands called the endocrine system. The endocrine system is responsible for coordinating many of the body's activities. The thyroid gland manufactures hormones that regulate the body's metabolism (the process of creating and using energy). There are several different disorders that can arise when the thyroid produces too much hormone (hyperthyroidism) or not enough (hypothyroidism).
Four common thyroid disorders include Hashimoto's disease, Graves' disease, goiter, and thyroid nodules.
Hashimoto's disease is also known as chronic lymphatic thyroiditis. It’s the most common cause of hypothyroidism in the United States. It can occur at any age, but it’s most common in middle-aged women. The disease occurs when the body's immune system mistakenly attacks and slowly destroys the thyroid gland and its ability to produce hormones.
Some people with mild cases of Hashimoto's disease may have no obvious symptoms. The disease can remain stable for years and symptoms are often subtle. They’re also not specific, which means they mimic symptoms of many other conditions. Symptoms include:
- mild weight gain
- dry skin
- dry, thinning hair
- pale, puffy face
- heavy and irregular menstruation
- intolerance to cold
- enlarged thyroid (goiter)
Hashimoto’s Diagnosis and Treatment
Testing the level of thyroid-stimulating hormone (TSH) is often the first step when screening for any type of thyroid disorder. Your doctor might order a blood test to check for increased levels of TSH as well as low levels of thyroid hormone (T3 or T4) if you’re experiencing some of the above symptoms. Hashimoto’s disease is an autoimmune disorder, so the blood test would also show abnormal antibodies that might be attacking the thyroid.
There is no known cure for Hashimoto's disease. Hormone-replacing medication is often used to raise thyroid hormone levels or lower TSH levels. It can also help relieve the symptoms of the disease. Surgery might be necessary to remove part or all of the thyroid gland in rare advanced cases of Hashimoto’s. The disease is usually detected at an early stage and remains stable for years because it progresses slowly.
Graves’ disease was named for the doctor who first described it more than 150 years ago. It’s the most common cause of hyperthyroidism (overactive thyroid). It’s an autoimmune disorder and occurs when the body's immune system mistakenly attacks the thyroid gland. This can cause the gland to overproduce the hormone responsible for regulating metabolism. The disease is hereditary and may develop at any age in men or women, but it’s much more common in women ages 20 to 30, according to the Department of Health and Human Services. Other risk factors include stress, pregnancy, and smoking.
The body's systems speed up and cause symptoms that are common to hyperthyroidism when there’s a high level of thyroid hormone in the bloodstream. Symptoms include:
- hand tremors
- increased or irregular heartbeat
- excessive sweating
- difficulty sleeping
- diarrhea or frequent bowel movements
- altered menstrual cycle
- enlarged thyroid (goiter)
- bulging eyes and vision problems
Graves’ Disease Diagnosis and Treatment
A simple physical exam can reveal an enlarged thyroid, enlarged bulging eyes, and signs of increased metabolism, including rapid pulse and high blood pressure. Your doctor will also order blood tests to check for high levels of thyroxine (T4) and low levels of TSH, both of which are signs of Graves' disease. A radioactive iodine uptake might also be administered to measure how quickly the thyroid takes up iodine, which it needs to function properly. A high uptake of iodine is consistent with Graves' disease.
There is no treatment to stop the immune system from attacking the thyroid gland and causing it to overproduce hormones. However, the symptoms of Graves' disease can be controlled in several ways, often with a combination of treatments:
- beta blockers to control rapid heart rate, anxiety, and sweating
- anti-thyroid medications to prevent the thyroid from producing excessive amounts of hormone
- radioactive iodine to destroy all or part of the thyroid
- surgery to remove the thyroid gland, a permanent option for patients who cannot tolerate anti-thyroid drugs or radioactive iodine
Successful hyperthyroidism treatment usually results in hypothyroidism. You’ll have to take hormone-replacement medication from that point forward. Graves' disease can lead to heart problems and brittle bones if it’s left untreated.
Goiter is a noncancerous enlargement of the thyroid gland. The most common cause of goiter worldwide is iodine deficiency in the diet. Goiter is often caused by (and a symptom of) hyperthyroidism in the United States, where iodized salt provides plenty of iodine. Goiter can affect anyone at any age, especially in areas of the world where foods rich in iodine are in short supply. However, goiters are more common after the age of 40 and in women, who are more likely to have thyroid disorders. Other risk factors include family medical history, certain medication usage, pregnancy, and radiation exposure.
There might not be any symptoms if the goiter is not severe. The goiter may cause one or more of the following symptoms if it grows large enough, depending on the size:
- swelling/tightness in the neck
- breathing and/or swallowing difficulties
- coughing or wheezing
- hoarseness of voice
Goiter Diagnosis and Treatment
Your doctor will feel the neck area and have you swallow during a routine physical exam. Blood tests will reveal the levels of thyroid hormone, TSH, and antibodies in the bloodstream. This will diagnose thyroid disorders that are often a cause of goiter. An ultrasound of the thyroid can check for swelling or nodules.
Goiter is usually treated only when it becomes severe enough to cause symptoms. You can take small doses of iodine if goiter is the result of iodine deficiency. Radioactive iodine can shrink the thyroid gland. Surgery will remove all or part of the gland. The treatments usually overlap because goiter is often a symptom of hyperthyroidism.
Goiters are often associated with highly treatable thyroid disorders, such as Graves' disease, and aren’t usually a cause for concern. However, they can cause serious complications if they’re left untreated. These complications can include difficulty breathing and swallowing.
Thyroid nodules are growths that form on or in the thyroid gland. The causes are not always known but can include iodine deficiency and Hashimoto's disease. The nodules can be solid or fluid-filled. Most are benign, but they can also be cancerous in a small percentage of cases. As with other thyroid-related problems, nodules are more common in women than men and the risk in both sexes increases with age.
Most thyroid nodules do not cause any symptoms. However, if they grow large enough, they can cause swelling in the neck and lead to breathing and swallowing difficulties, pain, and goiter. Some nodules produce thyroid hormone, causing abnormally high levels in the bloodstream. When this happens, symptoms are similar to those of hyperthyroidism and can include:
- high pulse rate
- increased appetite
- weight loss
- clammy skin
On the other hand, symptoms will be similar to hypothyroidism if the nodules are associated with Hashimoto's disease. This includes:
- weight gain
- hair loss
- dry skin
- cold intolerance
Thyroid Nodules Diagnosis and Treatment
Most nodules are detected during a normal physical exam. They can also be detected during an ultrasound, CT scan, or an MRI. Once a nodule is detected, other procedures — TSH test and a thyroid scan — can check for hyperthyroidism or hypothyroidism. A fine-needle aspiration (FNA) biopsy is used to take a sample of cells from the nodule and determine whether the nodule is cancerous.
Benign thyroid nodules are not life threatening and usually don't need treatment. Typically, nothing is done to remove the nodule if it doesn’t change over time. Your doctor may do another biopsy and recommend radioactive iodine to shrink the nodules if it grows.
Cancerous nodules are pretty rare — according to the National Cancer Institute, thyroid cancer affects barely 4 percent of the population. The treatment your doctor recommends will vary depending on the type of tumor. Removing the thyroid through surgery is usually the treatment of choice. Radiation therapy is sometimes used with or without surgery. Chemotherapy is often required if the cancer spreads to other parts of the body.
Make sure to discuss the diagnosis and treatment options with your doctor if you have a thyroid condition. Take any medication as prescribed. You should also report any serious side effects or symptoms.