Subacute thyroiditis secondary to a viral infection is known as?

• A. De Quervain Thyroiditis
• B. Hashimoto's thyroiditis
• C. Graves disease
• D. Goiter

Answer: (A)

Subacute thyroiditis after a viral illness is De Quervain thyroiditis. This condition is a painful, tender thyroid that often follows a recent viral infection and represents a granulomatous inflammatory process damaging the thyroid follicles. It typically has a short course with an initial thyrotoxic phase from leakage of preformed hormone, possibly followed by a hypothyroid phase, and then recovery. Inflammation lowers radioactive iodine uptake, and ESR is usually elevated, reflecting the inflammatory nature rather than autoimmune activity.

Hashimoto’s thyroiditis is an autoimmune, usually painless enlargement that progresses to hypothyroidism and involves thyroid antibodies, not a post-viral, painful thyroiditis.

Graves disease is autoimmune hyperthyroidism characterized by symptoms of excess thyroid hormone, diffuse uptake on imaging, and often eye findings.

Goiter simply means an enlarged thyroid from various causes and does not define a post-viral inflammatory process.