Clinical data: a 48-year-old woman was referred for an evaluation of neck pain lasting for 3 weeks. She had subfebrility.

Palpation: both thyroids were painfully enlarged.

Functional state: hyperthyroidism with TSH undetectable, FT4 27.9 pM/L, sedimentation rate 68 mm/H.

Ultrasonography: the thyroid was composed of hypoechogenic areas in around 50% of both lobes. The vascularization was decreased.

Cytological diagnosis: benign subacute, de Quervain's thyroiditis.