Which extrathyroidal manifestation is commonly associated with Graves' disease?

• A. Exophthalmos
• B. Goiter
• C. Hypertension
• D. Palpitations

Answer: (A)

Graves' disease often shows tissue changes outside the thyroid, and the most classic extrathyroidal sign is exophthalmos. The autoimmune process produces antibodies against the TSH receptor that not only drive overproduction of thyroid hormone but also activate orbital fibroblasts and adipocytes. This leads to inflammation and the accumulation of extracellular matrix components like glycosaminoglycans, causing edema and expansion of the orbital contents, particularly the extraocular muscles and fat. The result is forward displacement of the eye, or exophthalmos, along with possible lid retraction and double vision. While goiter can accompany Graves, and systemic thyrotoxic symptoms like palpitations and hypertension can occur, exophthalmos is the hallmark extrathyroidal manifestation that is most characteristic of Graves' disease.