Which histological finding is associated with Graves disease?

Which histological finding is associated with Graves disease?

• A. Scalloped colloid
• B. Lymphocytic infiltrate with germinal centers
• C. Fibrous tissue replacement
• D. Multinucleated giant cells

Answer: (A)

The key concept is that Graves disease causes diffuse stimulation of the thyroid by autoantibodies to the TSH receptor, leading to marked thyroid cell proliferation and turnover. Histologically, you see follicles lined by tall, crowded follicular cells with papillary infoldings, and the colloid within those follicles develops scalloped, irregular margins because it is being actively resorbed by the hyperactive epithelium. This scalloped colloid is a classic clue for Graves disease. In contrast, other patterns point to different thyroiditis: Hashimoto thyroiditis often shows lymphocytic infiltrates with germinal centers; Riedel’s thyroiditis features fibrous tissue replacing thyroid parenchyma; subacute (de Quervain) thyroiditis shows granulomatous inflammation with multinucleated giant cells.

The key concept is that Graves disease causes diffuse stimulation of the thyroid by autoantibodies to the TSH receptor, leading to marked thyroid cell proliferation and turnover. Histologically, you see follicles lined by tall, crowded follicular cells with papillary infoldings, and the colloid within those follicles develops scalloped, irregular margins because it is being actively resorbed by the hyperactive epithelium. This scalloped colloid is a classic clue for Graves disease.

In contrast, other patterns point to different thyroiditis: Hashimoto thyroiditis often shows lymphocytic infiltrates with germinal centers; Riedel’s thyroiditis features fibrous tissue replacing thyroid parenchyma; subacute (de Quervain) thyroiditis shows granulomatous inflammation with multinucleated giant cells.