Clinical presentation: a 64-year-old woman was referred for an evaluation of clinical symptoms suggesting hyperthyroidism.

Palpation: no abnormality.

Hormonal investigation: indicated euthyroidism with TSH-level 2.98 mIU/L. Anti-TPO was elevated 306 U/mL.

Ultrasonography: there were small hypoechogenic areas in both lobes. The largest one contained hyperechogenic foci.

Cytology: lymphocytic thyroiditis.