A 32-year-old woman presents with painless goitre and hypothyroidism. Anti-TPO antibodies are markedly elevated. Histology of the thyroid shows dense lymphocytic infiltrate with germinal centres, atrophic follicles lined by cells with abundant eosinophilic granular cytoplasm, and interstitial fibrosis. The eosinophilic granular cells represent:
- A Squamous metaplasia of follicular epithelium
- B Hürthle cell (oncocytic) change due to mitochondrial accumulation ✓
- C Parafollicular C cell hyperplasia
- D Papillary carcinoma nuclear transformation
Correct answer: B. Hürthle cell (oncocytic) change due to mitochondrial accumulation
Explanation
Hashimoto thyroiditis is characterised by lymphoid germinal centres, atrophic thyroid follicles and Hürthle cell metaplasia, which is oncocytic change caused by massive accumulation of mitochondria within follicular epithelial cells, giving abundant granular eosinophilic cytoplasm. Squamous metaplasia may occur but is not the described granular cell. C cell hyperplasia is a feature of MEN2, not Hashimoto, and papillary nuclear transformation is not part of this entity.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.