The Endocrine System
All of the following are true about Hashimoto’s thyroiditis, except? (AIIMS Nov 2014)
|B||Increase in lymphocytes|
|D||Orphan Annie eye nuclei|
Pathological features of Hashimoto's thyroiditis
a. Gross features
i. Diffuse symmetrically enlarged thyroid
ii. Although the gland is symmetrically enlarged, the accentuation of lobulations may make the gland appear lobular on gross examination.
iii. Capsule is intact
iv. Cut surface is pale, yellow firm and lobulated.
b. Microscopic features
i. Atrophy of thyroid follicles (atrophic follicles)
ii. Extensive lymphoplasmacytic infiltrate with abundant small lymphocytes and plasma cells with destruction of follicles
iii. Oncocytic metaplasia (Hurthle cell metaplasia) →The surviving follicular epithelial cells are commonly transformed into large cells with abundant pink cytoplasm and are known as Hurthle cells.
iv. Oncocytic metaplasia (Hurthle cell metaplasia) is also known "oxyphilic change" in epithelial cells and is considered the hallmark of Hashimoto's thyroiditis.
v. Varying degree of fibrosis and foci of squamous metaplasia within atrophic follicles.
vi. Interstitial connective tissue is increased and may be abundant.