TgAB very high

[Curious123]

Update. My latest bloods show the 100mcg levothyroxine has finally gotten me back into range:

TSH : 0.98 (0.4-3.5)

FT4 : 15.7 (9.0-19.0)

FT3 : 4.5 (2.6-6.0)

But my TgAB have shot up significantly to 173.2 (<4.1). TPO still negative at 2.4 (<5.6) and TSI not tested.

Any thoughts on very high TgAB? I am still waiting to see an endocrinologist.

[greygoose]

It means that the cause of your hypothyroidism is autoimmune thyroiditis - Hashi's or Ord's. You can expect antibodies to go up and down, they fluctuate all the time, it doesn't mean anything. And once you've had a positive result, there's not really much point in testing a second time.

Why would you want your TSI tested? That's for hyperthyroidism/Graves'. If you're taking 100 mcg levo, then you are hypo.

[Curious123 in reply to greygoose]

I had positive TSI earlier and went hyperthyroid initially.

[greygoose in reply to Curious123]

OK, I see. Very strange. What is your diagnosis?

[Curious123 in reply to greygoose]

It was postpartum thyroiditis but not sure if that is going to change now once I see a specialist. I also went hyperthyroid in Jul20 but managed to move thyroid and antibodies back to normal without thyroxine. The endocrinologist at that time deemed it a mild thyroiditis and said it wasn’t autoimmune. My TgAB antibodies were raised that instance but after the thyroid started normalising and only got to 10.5 so the 173.2 is a new ball game being >42 times the upper limit.

[greygoose in reply to Curious123]

I also went hyperthyroid in Jul20 but managed to move thyroid and antibodies back to normal without thyroxine.

Well, you didn't do it. It did it by itself. That's how autoimmune thyroiditis 'works', it swings between hypo and hyper as the immune system slowly destroys the thyroid. And if you have high antibodies, then it is autoimmune. Your endo is talking rubbish, as most of them do. But, you wouldn't take thyroxine for hyper, anyway. It's not a 'cure' for a wonky thyroid. It's thyroid hormone replacement - the thyroid hormone T4.

But, as I said before, if antibody levels are over-range, it's positive for AIT. The exact level of the antibodies is irrelevant.