text: Subacute thyroiditis. With subacute thyroiditis the thyroid stimulating immunoglobulins should be negative, and if a radioactive iodine uptake scan is performed it usually won't be elevated, as the reading will usually be low. Plus, the person most likely won't have any thyroid eye disease symptoms. In addition, the symptoms of hyperthyroidism usually are temporary, as they usually last from two to four months, and is then usually followed by a period of hypothyroidism. I talk about this condition in greater detail in an article I wrote entitled "Natural Treatment Methods For Subacute Thyroiditis".
  Toxic multinodular goiter. This condition involves the presence of hyperthyroidism along with a goiter and multiple thyroid nodules. Most people with toxic multinodular goiter will also have negative thyroid stimulating immunoglobulins, although occasionally I'll work with someone who has both Graves' Disease and toxic multinodular goiter. But this is uncommon, as most people with this condition will have negative thyroid antibodies, won't have the symptoms of thyroid eye disease, and if they have a radioactive iodine uptake scan this usually will reveal low readings. I spoke more about this condition in an article I wrote entitled "Multinodular Goiter and Natural Treatment Methods".