Clinical presentation: A 35-year-old woman was referred for evaluation of a recurrent hyperthyroidism. The patient's first hyperthyroidism occurred 12 years ago when treated with medication for two years. Her recurred two months before the present examination. In contrast with the first attack of hyperthyroidism, at this time eye complaints have also appeared.

Palpation: no abnormality. Both lobes were a bit tender. There were no palpable nodules.

Laboratory investigations: TSH 0.001 mIU/L, FT4 44.3 pM/L, TSAb 7.0 U/L (normal value < 1.5).

Ultrasonography. The thyroid was echonormal and presented numerous more hypoechogenic areas. None of them fit to a nodule in pathological sense. The vascularization was moderately increased.

Summary of follow-up. The patient was treated by methimazole. Five weeks after starting of methimazole therapy, the FT4 level became normal. Despite steroid therapy her eye symptoms have not ceased. Therefore, surgery was advised.

Histopathology: Diffuse goiter. Chronic lymphocytic thyroiditis.