A Case of Thyroid Hemiagenesis Associated With Graves' Disease and Follicular Neoplasm

Thyroid hemiagenesis is a rare congenital anomaly in which the thyroid lobe fails to develop, and the occurrence of thyroid hemiagenesis with other thyroid diseases is possible. Here, we report a case of thyroid hemiagenesis with Graves’ disease and follicular neoplasm. Our patient, an 81-year-old female, was admitted with general weakness and weight loss over the previous month. Laboratory testing showed elevated free T4, suppressed TSH, and elevated TSH receptor antibody levels. A 99mTc thyroid scan showed absent uptake in the left lobe and a cold nodule on the isthmus of the thyroid gland. Ultrasound imaging showed an oval-shaped thyroid nodule on the isthmus and diffuse enlargement and hypervascularity of the right lobe. We performed ultrasound-guided fine needle aspiration, and cytologic analysis showed evidence of a Hurthle cell follicular neoplasm. To date, this is the first reported case of thyroid hemiagenesis associated with Graves’ disease and Hurthle cell follicular neoplasm. J Med Cases. 2015;6(8):385-387 doi: http://dx.doi.org/10.14740/jmc2189w