A Rare Variant of Hashimoto's Thyroiditis

Abstract

Hashimoto's thyroiditis (HT) is the most frequently diagnosed thyroid disorder worldwide, characterized by hypothyroidy and thyroid autoimmunity. The fibrous variant accounts for a small number of cases. A 48 years old woman, with 20-years history of Hashimoto thyroiditis presented for a large recent goiter with compressive symptoms, in hypothyroidic state and with very high thyroid antibodies antithyroglobulin and antithyroperoxidase. Ultrasound and fine needle aspiration biopsy showed an enlargement of the thyroid gland with nonhomogeneous structure and trachea shifting posteriorly, Bethesda III. CT scan showed similar aspect of the thyroid gland with compression on the trachea and the left common jugular vein. Surgery was performed due to suspicion of malignancy and compression symptoms. Thyroidectomy was uneventful, but the patient developed hypoparathyroid symptoms postoperatively that resolved with high dose calcium, magnesium and vitamin D supplementation. The pathology report was consistent of Hashimoto's thyroiditis fibrous variant. This case report presents a rare case of the fibrous variant of Hashimoto's thyroiditis that is rarely taken under consideration in the preoperative setting as diagnosis is hard to establish with the usual algorithm of imaging and FNA biopsy. The multidisciplinary management in pre-and postoperative approach and evaluation are of utmost importance for successful management of such case.

Keywords: Hashimoto’s thyroiditis; fibrous variant; thyroidectomy.

Figure 1

CT scan images of the cervical region

Figure 2

Gross histopathology specimens

Figure 3

Histopathology identifies atrophic remnant follicles sometimes bordered by Hurtle cells (A), with interstitial fibrosis (B), surrounded by chronic inflammatory infiltrate (C), with secondary lymph follicle pattern (D). HE staining, A-20×; B-10×; C, D- 4×.