Dr. M.J. Bazos,
Patient Handout
THYROIDITIS
About Your
DiagnosisThe 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
DiagnosisSigns 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.TreatmentHashimoto’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.Websites:American
Thyroid Association: http://www.thyroid.org\patient\.The
Thyroid Foundation of Canada http://home.ican.net/~thyroid/guides.