I had a goiter that originally caused my hyperthyroidism from lack of iodine in my diet (my mother thought non ionized salt was better), treated with RAI and I've been on 125mcg synthroid for the last couple of years, I just assumed my thyroid was pretty much dead and the chance of another goiter non existent... till my mother recently mentioned she had one, considering I've been using non ionized sea salt and probably no getting it anywhere else... one side of my thyroid does seem to have become a little bigger and I've experienced some weight loss and have been unable to gain (as in I'm at < than 100lbs these days, a loss of 15lbs), what should I be looking for in my tests? My doctor just looks at my THS and Free T4
A goiter is a swollen, inflamed thyroid and yes, it's possible for your thyroid to become swollen and inflamed more than once, for more than one reason...
What caused your hyperthyroidism 10 yrs ago? Apparently, you had some type of anti-thyroid medication, TT or RAI that caused you to go hypo? Are you currently taking replacement thyroid hormone medication?
Have you ever been tested for, either, Graves Disease or Hashimoto's? Graves Disease is always associated with hyperthyroidism. Hashimoto's is, typically, associated with hypothyroidism, but early stages are often characterized by periods of hyperthyroidism, which can switch back and forth between hypo and normal for years before you finally become permanently hypo...
The tests you need to diagnose Hashimoto's are Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TgAb). Thyroid Stimulating Immunoglobulin (TSI) is the definitive test for Graves Disease.
Hashimoto's and Graves Disease are, both, autoimmune conditions. Autoimmune conditions tend to run in families, though not every member of a family will get the same autoimmune condition. For instance, I have Hashimoto's and Pernicious Anemia, my son has Type I Diabetes and my daughter has Lupus. Once a person has one autoimmune condition, the chance of getting another are much greater than the general population.
Once you have an autoimmune disease, you have it for life, even though it may go into remission.
Both, too little and too much iodine can cause hypothyroidism...