Clinical presentation: a 52-year-old woman with fever and painful thyroid for a week. She suffered from upper airways infection two months before the present examination.

Palpation: both thyroids were hard and painful.

Functional state: mild hyperthyroidism with TSH-level 0.01 mIU/L, FT4 23.1 pM/L, We 68 mm/H, CRP 13.8 mg/L.

Ultrasonography: diffusely moderately hypoechogenic lobes with several circumscribed, even more hypoechogenic areas with blurred border.

Cytological and final diagnosis: subacute, granulomatous de Quervain's thyroiditis.

Suggestion: steroid therapy.