All Sample Questions

Thyroid Dysfunction 1

Question

Question: A 25-year-old woman presents to her physician complaining of fatigue, cold intolerance, weight gain, and constipation. Physical examination reveals a slow heart rate, dry skin, and swelling around her eyes and face. Laboratory tests show decreased serum free T3 and T4 levels, and increased serum TSH levels. A biopsy of the patient's thyroid gland is shown below. Which of the following histological findings is most likely seen in this patient's biopsy?

Choices

A) Papillary structures with ground-glass nuclei

B) Enlarged follicles filled with a colloid substance

C) Granulomatous inflammation with giant cells

D) Hurthle cells

E) Lymphocytic infiltrate with germinal centers

Answer

E) Lymphocytic infiltrate with germinal centers

Explanation

The patient's symptoms of fatigue, cold intolerance, weight gain, constipation, slow heart rate, dry skin, and facial edema, along with decreased free T3 and T4 levels and increased TSH levels, are suggestive of hypothyroidism. The most common cause of hypothyroidism in iodine-sufficient areas is Hashimoto's thyroiditis, an autoimmune disease in which the body's immune system attacks and gradually destroys the thyroid gland. Histologically, Hashimoto's thyroiditis is characterized by a dense lymphocytic infiltrate with the formation of germinal centers. In contrast, the other choices represent findings in other thyroid conditions: papillary structures with ground-glass nuclei are seen in papillary thyroid cancer (Choice A), enlarged follicles filled with a colloid substance are seen in goiter (Choice B), granulomatous inflammation with giant cells is seen in subacute thyroiditis (Choice C), and Hurthle cells are seen in Hashimoto's thyroiditis but are not the most characteristic feature (Choice D).