Graves' disease. Initial presentation with exophthalmos and solitary hot nodule

A 52-year-old man presented with left exophthalmos. A thyroid scan showed a right lobe hot nodule with suppression of the remainder of the gland. Thyroid function tests were normal. In less than two years, the patient had worsening of the exophthalmos. Thyroid indices then revealed hyperthyroidism and the thyroid image had markedly altered (with evidence of diffuse function). This change, initially showing a hot nodule and then diffuse thyroid overactivity, has been reported previously in three cases (all women). Characteristics of the disorder in these four individuals were reviewed. It is possible that the patients had two distinct diseases, separated temporally.