(See also Overview of the Thyroid Gland.)
Silent lymphocytic thyroiditis occurs most often among women, typically three to four months after childbirth, and causes the thyroid to become enlarged without becoming tender. The disorder recurs with each subsequent pregnancy.
For several weeks to several months, people have an overactive thyroid gland (hyperthyroidism) followed by an underactive thyroid gland (hypothyroidism) before eventually recovering normal thyroid function.
Silent lymphocytic thyroiditis begins in the 3 to 4 months following childbirth. It starts with a hyperthyroid phase when the thyroid gland gets bigger without any pain or tenderness. Then the woman develops hypothyroidism before the condition usually resolves on its own. During the second phase, the woman may experience symptoms of hypothyroidism, which may include fatigue, weight gain, constipation, dry skin and hair, and cold intolerance.
The diagnosis of silent lymphocytic thyroiditis is made based on a person's symptoms and the results of the examination and thyroid function tests. Rarely, doctors do a biopsy of the thyroid to confirm the diagnosis.
If a woman developed silent lymphocytic thyroiditis after a pregnancy, doctors usually test for the disorder after subsequent pregnancies.
Hyperthyroidism may require treatment for a few weeks, often with a beta-blocker such as atenolol. Beta-blockers help control many of the symptoms of hyperthyroidism. For example, these drugs can slow a fast heart rate, reduce tremors, and control anxiety.
During the period of hypothyroidism, the person may need to take thyroid hormone, usually for no longer than about 12 months. However, hypothyroidism becomes permanent in about 10% of people with silent lymphocytic thyroiditis, and these people must take thyroid hormone for the rest of their life.