A 51-year-old woman comes to the office due to progressively worsening fatigue, weight gain, and constipation for the past 6 months. The patient has had difficulty performing daily activities due to her fatigue. She has no significant medical history and takes no medications. The patient has no drug allergies and does not use tobacco, alcohol, or illicit drugs. Blood pressure is 110/80 mm Hg and pulse is 55/min. Physical examination shows mild, diffuse enlargement of the thyroid gland. Cardiopulmonary and abdominal examinations are normal. Biopsy of this patient's thyroid is most likely to show which of the following findings?

Question

A 51-year-old woman comes to the office due to progressively worsening fatigue, weight gain, and constipation for the past 6 months.  The patient has had difficulty performing daily activities due to her fatigue.  She has no significant medical history and takes no medications.  The patient has no drug allergies and does not use tobacco, alcohol, or illicit drugs.  Blood pressure is 110/80 mm Hg and pulse is 55/min.  Physical examination shows mild, diffuse enlargement of the thyroid gland.  Cardiopulmonary and abdominal examinations are normal.  Biopsy of this patient's thyroid is most likely to show which of the following findings?

Quizplus · Accepted Answer

11ec160b_3915_9673_9249_191ce333f647_MD0001_00 This patient has chronic lymphocytic (Hashimoto) thyroiditis presenting with hypothyroidism (eg, fatigue, weight gain, constipation) and a diffuse goiter. This autoimmune disease occurs predominately in women, has a peak incidence at age 45-65, and is the most common cause of hypothyroidism in iodine-sufficient regions such as the United States. In all forms of primary hypothyroidism, laboratory studies show low serum thyroxine (T4) levels and elevated TSH. Antithyroid peroxidase antibody levels are usually elevated, although they are not specific to Hashimoto thyroiditis and are also seen in other autoimmune thyroid disorders (eg, postpartum thyroiditis, Graves disease). If the diagnosis is uncertain (eg, thyroid nodularity), a biopsy can be performed to rule out malignancy. Characteristic findings of Hashimoto thyroiditis include a lymphoplasmacytic infiltrate with the formation of germinal centers. Residual follicles are often surrounded by Hürthle cells (large cells with granular, eosinophilic cytoplasm) representing follicular epithelial cells that have undergone metaplastic change in response to inflammation. (Choice A) Histopathology in papillary thyroid carcinoma shows branching papillary structures with concentric calcifications (psammoma bodies) and ground-glass or empty-appearing nuclei ("Orphan Annie eye" nuclei). However, papillary thyroid carcinoma typically presents as an enlarging nodule in a clinically euthyroid patient. (Choice B) Riedel thyroiditis is characterized by extensive fibrosis of the thyroid extending into the surrounding structures. The fibrotic gland is typically hard and fixed, often resembling a malignancy. (Choice C) Graves disease presents with hyperthyroidism associated with a diffuse goiter, exophthalmos, and pretibial myxedema. Microscopy shows hyperplastic follicles with tall, crowded follicular epithelial cells projecting into the follicular lumen; hyperactive reabsorption causes scalloping around the edges of the colloid. (Choice E) Subacute granulomatous (de Quervain/postviral) thyroiditis is characterized by the disruption of follicles and a mixed cellular infiltrate with occasional multinucleated giant cells. It typically presents after a viral upper respiratory infection with fever and a painful, tender thyroid. Educational objective: Chronic lymphocytic (Hashimoto) thyroiditis is a common cause of primary hypothyroidism. Histopathology findings include intense lymphoplasmacytic infiltrate, often with germinal centers. Residual follicles may be surrounded by Hürthle cells (large cells with granular, eosinophilic cytoplasm).

A 51-Year-Old Woman Comes to the Office Due to Progressively