De Quervain's thyroiditis - Figure 2. Sonographic presentation - natural course of the disease.

In most cases the disease affects initially one lobe but the contralateral lobe will be affected in most if not all of the cases even when the inflammation is stopped by steroids or ceases by itself.
In this case at first examination (first row) the left thyroid was painful whie the right was intact. 3 weeks later the latter presented signs of thyroiditis while the hypoechogenic areas decreased in the left lobe.