De novo Graves' thyroid eye disease after radioiodine treatment for toxic nodular thyroid disease.

It is well known that radioactive iodine treatment (RAI) for thyrotoxicosis in Graves' disease can precipitate worsening of thyroid eye disease (TED), particularly in susceptible patients. Less commonly, it has been associated with de novo development of TED in those with Graves' disease without a history. Prophylactic steroid treatment has been shown to reduce the incidence of this phenomenon in those with risk factors.Here, we describe a patient with thyrotoxicosis due to nodular thyroid disease rather than Graves' disease and normal baseline thyroid-stimulating hormone receptor antibody (TRAb) levels and no other risk factors for TED, who subsequently developed new onset TED associated with thyrotoxicosis and elevated TRAb levels following RAI.