Hashimoto's disease is best described as which?

• A. Autoimmune destruction of adrenal cortex causing Addison's.
• B. Autoimmune destruction of thyroid leading to hypothyroidism; also called chronic lymphocytic thyroiditis.
• C. Infectious destruction of thyroid.
• D. Hypersecretion of thyroid hormone.

Answer: (B)

Hashimoto's disease is an autoimmune thyroiditis in which the immune system attacks the thyroid gland, leading to gradual destruction of thyroid tissue and resulting in hypothyroidism. This is why it’s also called chronic lymphocytic thyroiditis—the thyroid becomes infiltrated with lymphocytes and often develops fibrosis. The autoimmune nature is hinted by antibodies such as anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin, and the typical lab pattern in established disease is elevated TSH with low free T4. Clinically, patients may experience fatigue, weight gain, cold intolerance, dry skin, and sometimes a goiter. Treatment is lifelong thyroid hormone replacement with levothyroxine. Describing autoimmune destruction of the adrenal cortex would refer to Addison's disease, infectious destruction of the thyroid is not characteristic of Hashimoto's, and hypersecretion of thyroid hormone describes hyperthyroidism, the opposite of Hashimoto's.