2 CASES OF GRAVES-DISEASE WITH PRESENTATION OF UNILATERAL DIFFUSE UPTAKE OF RADIOISOTOPES

We present two cases of Graves' disease whose initial thyroidal scinti scan with 99mTcO4- (Case 1) and I-123 (Case 2) showed unilateral diff use uptake of radioisotopes. Initial diagnosis was possibility of mali gnancy in Case 1 and Graves' disease or Plummer's disease in Case 2. B oth cases underwent right hemithyroidectomy. Histopathology of the res ected thyroid gland in both showed hyperplastic columnar epithelium an d infiltrative lymphocytes which was compatible with Graves' disease. Twenty seven (Case 1) and eight months (Case 2) after operation, both presented with thyrotoxic symptoms associated with enlarged left lobe, increased serum free thyroid hormone concentrations, suppressed TSH c oncentration, increased thyroidal I-123 uptake in the remaining left l obe, and positive thyrotropin receptor antibodies. Both cases were suc cessfully treated with methimazole. It was concluded that initial radi oisotope uptake as well as scintigram in rare subgroup of patients wit h Graves' disease could be simillar with that of non-autoimmune autono mous goiter (Plummer's disease),