We performed an 131I thyroid imaging on a 26-year-old man who had the clinical features of thyrotoxicosis. Physical examination revealed no goiter, no palpable nodules, and no tenderness. The imaging showed decreased activity of bilateral thyroid lobes with depressed radioactive iodine uptake. The thyroid function test showed thyrotoxicosis. Thyroglobulin antibody and microsomal antibody were undetectable. ESR was 2 mm/h (normal 0-15 mm/h). While being confronted with this information, the patient admitted he was secretly taking L-thyroxine to cut down his weight. Reviewing the clinical history and data, the possibility of subacute thyroiditis was ruled out, and the results of tests confirmed the diagnosis of thyrotoxicosis factitia. As the similarities in thyroid function tests, 131 I uptake and scan, differential diagnosis between subacute thyroiditis and thyrotoxicosis factiti is important. We report here such a case. Key words: 131 I, thyroid uptake and scan, thyrotoxicosis factitia, hyperthyroidis
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.