Hypothyroid Hashimoto's Thyroiditis with Scintigraphic and Color Flow Doppler Sonography Features Mimicking a Hot Nodule

Abstract

We report a 59-year-old woman who had Hashimoto's thyroiditis (HT) with hypothyroidism. A solid hypervascularized nodule in the right lobe was detected by color flow doppler sonography (CFDS). Thyroid ^99mTc pertechnetate scintigraphy revealed a hot area in the right lobe. After three months, thyroid function tests also revealed hypothyroidism and ¹³¹I scintigraphy was similar to the previous scintigraphy. No nodular or hypervascularized lesion in the right lobe could be identified at the sixth month of L-T4 substitution therapy. In conclusion, HT may present as a single hot nodule and hypothyroidism. Imaging findings of HT should be carefully evaluated for the precise diagnosis.