Dr. M.J. Bazos, Patient Handout

About Your Diagnosis
The thyroid is a small gland located in the center of the neck and is important for regulating metabolism. Thyroiditis literally means inflammation of the thyroid. The inflammatory reaction may result in either an overactive or an underactive thyroid gland. The most common type of thyroiditis is called Hashimoto’s thyroiditis. This occurs when the body’s own immune system attacks the thyroid cells, leading to decreased hormone production (hypothyroidism). Subacute and silent thyroiditis result in an overactive thyroid (hyperthyroidism), which resolves spontaneously over several weeks. Finally, postpartum thyroiditis occurs in women who were recently pregnant. Patients may go through both a hyperthyroid and hypothyroid phase of several weeks’ duration before returning to normal thyroid function. Some patients, however, may remain permanently hypothyroid. Hashimoto’s thyroiditis is a common disorder, occurring approximately 10 times more commonly in women than men. Up to 2% of women in the United States may be affected. Silent and subacute thyroiditis are much less common than Hashimoto’s disease, but recent evidence suggests that postpartum thyroiditis may occur in up to 5% to 7% of normal pregnancies, especially affecting those women who have a history of thyroid abnormalities before they were pregnant. Thyroiditis is detected through a careful medical history, physical examination, and measurement of blood tests, including thyroid hormone (T4 and T3), thyroid-stimulating hormone (TSH), and antithyroid antibodies. A radioactive iodine uptake (RAIU) may be measured in certain circumstances to help establish the diagnosis. In Hashimoto’s disease, the thyroid gland is mildly enlarged and has a lumpy texture. The T4 and T3 levels are low, and TSH levels are high, indicating hypothyroidism. The majority of patients have antibodies detected in the blood that react against the thyroid. Subacute thyroiditis occurs after a viral infection; the thyroid gland is enlarged and painful. An elevated erythrocyte sedimentation rate (ESR) is noted. The T4 and T3 levels are elevated and the TSH is suppressed. The RAIU is low. Silent thyroiditis has a presentation that is similar to subacute thyroiditis, except that the physical examination is normal. Postpartum thyroiditis is diagnosed in women 3–8 months after pregnancy. Depending on the timing of the blood work, the patient may be either hyperthyroid or hypothyroid. The RAIU is low. Thyroiditis is curable with appropriate medical treatment.

Living With Your Diagnosis
Signs and symptoms of thyroiditis vary depending on the type of thyroiditis and gland activity. Symptoms of hyperthyroidism, seen in silent, subacute, or early postpartum thyroiditis include weight loss, increased appetite, diarrhea, irregular menses, racing heart beat, anxiety, heat intolerance, and tremulousness. Patients who are hypothyroid, such as those with Hashimoto’s or late postpartum thyroiditis, may have weight gain, decreased appetite, constipation, fatigue, depression, cold intolerance, and weakness. If not treated, Hashimoto’s can progress to severe hypothyroidism with a decreased blood pressure and coma (myxedema). Silent thyroiditis usually resolves spontaneously after several weeks. Subacute thyroiditis may cause neck pain and swelling. Postpartum thyroiditis may have no effects, or may cause anxiety in the hyperthyroid phase, and depression and fatigue in the hypothyroid phase.

Hashimoto’s disease is treated by replacing the missing thyroid hormone. Most patients require between 75 and 150 micrograms of levothyroxine daily. Geriatric patients may require significantly less medicine. Levothyroxine is safe and well tolerated. Rapid replacement may exacerbate underlying coronary artery disease. Silent and subacute thyroiditis may resolve spontaneously without treatment or may require anti-inflammatory medicines, such as a nonsteroidal anti-inflammatory drug (NSAID) or prednisone for pain. A beta-adrenergic blocking drug such as Inderal or atenolol may be required for rapid heartbeats. This medication should be slowly tapered once symptoms abate.

The DOs
• Learn about the type of thyroiditis you have and whether your thyroid is overactive or underactive.
• Take your medication treatment as prescribed.
• Tell your doctor if you are pregnant or breastfeeding or wish to become pregnant soon.

The DON’Ts
• Don’t wait to seek treatment if you feel poorly.
• Don’t expect overnight response to treatment. Treatment requires 4–6 weeks before patients begin to feel better.
• Don’t have an RAIU if you are pregnant or breastfeeding.
• Don’t exercise vigorously if you are symptomatically hyperthyroid or hypothyroid.
• Don’t overeat.

When to Call Your Doctor
• You have chest pain, chest pressure, or palpitations after starting thyroid hormone replacement.
• You are pregnant, breast-feeding, or planning to become pregnant.
• You have a high fever or other severe illness.
• You have a rash or other reaction to your medications.
• You continue to feel poorly despite treatment for several weeks.

American Thyroid Association: http://www.thyroid.org\patient\.
The Thyroid Foundation of Canada http://home.ican.net/~thyroid/guides.