Thyroid antibodies

[StitchFairy]

I was going to purchase a self test and thought I'd include antibodies this time. Just out of curiosity to see if I still have any, having been on thyroid medication for many years now. I know NHS won't do this for me.

But disappointed to find Monitor My Health only offer testing for TPO. Not helpful for me as I've always been negative for TPO and positive for TGab. Medichecks do both but are much more expensive.

So presumably it's more common in hypothyroidism to have TPO antibodies than TGab? Anyone know why?

[SlowDragon Administrator]

Most autoimmune thyroid patients have just high TPO or high TPO AND high TG antibodies

But a significant minority of autoimmune thyroid patients ONLY have high TG antibodies and struggle to get diagnosed

NHS refuses to test TG antibodies unless TPO antibodies are high

So yes you would need to use Medichecks or Blue Horizon to test

[StitchFairy in reply to SlowDragon]

Thanks. I know when I was first diagnosed many years ago, GP said antibodies were off the chart. But in those days I was clueless, so I don't know whether they were TPO, TG or both!

[SlowDragon Administrator in reply to StitchFairy]

probably both ….or NHS wouldn’t have tested just TG antibodies even then

[helvella]

A review paper which might have some interest - and onward links if you wish to go further.

Utility of Antibodies in the Diagnoses of Thyroid Diseases: A Review Article

Gupta A1,

Kumar S1

Cureus, 20 Dec 2022, 14(11)

Thyroid Peroxidase Autoantibody

It is one of the first thyroid antibodies identified. It was later discovered that this antibody targets Thyroid Peroxidase (TPO), and these antibodies are used to diagnose AITD. The production of thyroid hormones is carried out by the trans-membrane protein TPO, which is found in the apical membrane of thyrocytes, and antibodies to TPO lead to AITD.

Thyroglobulin Specific Antibodies (TgAb)

More than 90% of those with HT have TgAb, which is also detectable in small amounts in the serum of those with GD. Twenty percent of people with normal thyroid function in the general population also have TgAb, which is most likely a sign of a sub-clinical AITD.

Full paper freely accessible here:

europepmc.org/article/PMC/P...

[StitchFairy in reply to helvella]

Dec2022! A very timely paper, thank you!