Thyroiditis (Also called de Quervains disease) is an inflammatory precess that can affect all or part of the gland. It is thought to be of viral etiology however, this is unproven.

Clinically these patients present with the findings of hyperthyroidism similar to Graves disease. However, the thyroid gland is usually tender. This entity needs to be differentiated from Graves' disease before any treatment is provided. This is accomplished by Imaging and I-131 uptake. I-131 uptake is increased in Graves Disease (>30%) and decresased in thyroiditis (<8%)