Inflammation of the thyroid gland occurs as autoimmune thyroiditis (long-term inflammatory disease), subacute
granulomatous thyroiditis (self-limiting inflammation), Riedel’s thyroiditis (rare, invasive fibrotic process), and
miscellaneous thyroiditis (acute suppurative, chronic infective, and chronic noninfective).

Causes and incidence
Autoimmune thyroiditis is due to antibodies to thyroid antigens in the blood. It may cause inflammation and lymphocytic
infiltration (Hashimoto’s thyroiditis). Glandular atrophy (myxedema) and Graves’ disease are linked to autoimmune

Subacute granulomatous thyroiditis usually follows mumps, influenza,
coxsackievirus, or adenovirus infection.
Riedel’s thyroiditis is a rare condition of unknown etiology.

Miscellaneous thyroiditis results from
bacterial invasion of the gland in acute suppurative thyroiditis; tuberculosis,
actinomycosis, or other infectious agents in the chronic infective form; and sarcoidosis and amyloidosis in
chronic noninfective thyroiditis. Postpartum thyroiditis (silent thyroiditis) is another autoimmune disorder associated
with transient thyroiditis in females within 1 year after delivery.

Thyroiditis is most prevalent among people ages 30 to 50 and is more common in females than in males. Incidence is
highest in the Appalachian region of the United States.

Signs and symptoms
Autoimmune thyroiditis is usually asymptomatic and commonly occurs in females, with peak incidence in middle age. It’
s the most prevalent cause of spontaneous hypothyroidism.

In subacute granulomatous thyroiditis, moderate thyroid enlargement may follow an upper respiratory tract infection or
a sore throat. The thyroid may be painful and tender, and dysphagia may occur.

In Riedel’s thyroiditis, the gland enlarges slowly as it’s replaced by hard, fibrous tissues. This fibrosis may compress
the trachea or the esophagus. The thyroid feels firm.

Clinical effects of miscellaneous thyroiditis are characteristic of pyogenic infection: fever, pain, tenderness, and
reddened skin over the gland.

Precise diagnosis depends on the type of thyroiditis:

❑ Autoimmune: high titers of thyroglobulin and microsomal antibodies present in serum

❑ Subacute granulomatous: elevated erythrocyte sedimentation rate, increased thyroid hormone levels, decreased
thyroidal radioiodine uptake

❑ Chronic infective and noninfective: varied findings, depending on underlying infection or other disease.

Appropriate treatment varies with the type of thyroiditis. Drug therapy includes levothyroxine for accompanying
hypothyroidism, analgesics and anti-inflammatory drugs for mild subacute granulomatous thyroiditis, propranolol for
transient hyperthyroidism, and steroids for severe episodes of acute inflammation. Suppurative thyroiditis requires
antibiotic therapy. A partial thyroidectomy may be necessary to relieve tracheal or esophageal compression in Riedel’s

Special considerations
Before treatment, obtain a patient history to identify underlying diseases that may cause thyroiditis, such as
tuberculosis or a recent viral infection.

❑ Check the patient’s vital signs, and examine her neck for unusual swelling, enlargement, or redness. Provide a
liquid diet if she has difficulty swallowing, especially when due to fibrosis. If the neck is swollen, measure and record
the circumference daily to monitor progressive enlargement.

❑ Administer antibiotics as ordered, and report and record elevations in temperature.

❑ Instruct the patient to watch for and report signs of hypothyroidism (lethargy, restlessness, sensitivity to cold,
forgetfulness, and dry skin), especially if she has Hashimoto’s thyroiditis, which often causes hypothyroidism.

❑ Check for signs of hyperthyroidism (nervousness, tachycardia, tremor, and weakness), which commonly occurs in
subacute thyroiditis.

❑ After thyroidectomy, check vital signs every 15 to 30 minutes until the patient’s condition stabilizes. Stay alert for
signs of tetany secondary to accidental parathyroid injury during surgery. Keep 10% calcium gluconate available for I.
V. use if needed. Assess dressings frequently for excessive bleeding. Watch for signs of airway obstruction, such as
difficulty in talking or increased swallowing; keep tracheotomy equipment handy.

❑ Explain to the patient that she’ll need lifelong thyroid hormone replacement therapy if hypothyroidism occurs. Tell
her to watch for signs of overdosage, such as nervousness and palpitations.

Copyright Details: Professional Guide to Diseases (Eighth Edition), Copyright © 2005 Lippincott Williams & Wilkins.