Clinical data: a 35-year-old woman with hypothyroidism replaced with 100 ug levo-tiroxin was referred for evaluation of thyroid nodules.

Functional state: euthyroidism.

Ultrasonography: there were several circumscribed areas which in fact did not fit nodules. These are active foci of autoimmune thyroiditis.

Cytological report: benign Hashimoto's thyroiditis.