USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

Which disorder is characterized by multi-nucleated giant cells, granulomatous inflammation, and preceded by a viral upper respiratory infection?

1. Empty sella syndrome

2. Hashimoto thyroiditis

3. Subacute granulomatous thyroiditis

4. Thyroid cancer

The correct answer is: Subacute granulomatous thyroiditis

The correct choice is indeed subacute granulomatous thyroiditis, also known as De Quervain thyroiditis. This condition is characterized by the presence of multi-nucleated giant cells and granulomatous inflammation in the thyroid gland, which typically follows a viral upper respiratory infection. In subacute granulomatous thyroiditis, the inflammation is a result of a viral infection, often associated with common respiratory viruses such as mumps, influenza, or Coxsackie virus. The immune response to these infections can lead to the formation of granulomas within the thyroid tissue, which is why multi-nucleated giant cells are noted in histological examinations. The other options presented do not match the clinical presentation described in the question. Empty sella syndrome pertains to a condition of the sella turcica, typically resulting from a pituitary disorder. Hashimoto thyroiditis is an autoimmune condition that primarily leads to hypothyroidism and features lymphocytic infiltration rather than granulomatous inflammation. Thyroid cancer involves abnormal growth of thyroid cells and does not typically present with the inflammatory changes seen in subacute granulomatous thyroiditis. Thus, the combination of being preceded by a viral infection and the specific histological findings of multinucleated giant cells