Hashimoto to Graves

[Doodi1]

Hi All,

I have been lurking as a member for >8years following a diagnosis of Hashimoto's thyroiditis. I have been managed with varying doses of levothyroxine, follow a gluten-free diet and supplement with B12, Fe and Vit D oral sprays. Having gained weight during Covid, I decided to make a conscious effort to loose the weight gained and joined WW, walked everywhere and exercised at the gym x3 weekly. I was fastidious with all 3 and lost 12kg (loss of approx. 15% in body weight). 10 months in to my WW journey on a routine blood test my Tsh measured < 0.02 ....... fast forward, repeat blood tests, dose reduction of thyroxine, I was referred to a lovely private endocrinologist (recommended to me by a member on this forum) who ran blood tests and an ultrasound of gland. I was diagnosed with sub-clinical hyperthyroidism, cause unknown, as had tested negative twice for Graves antibodies, no obvious nodules on scan and no history of prior illness. I have been monitored 3 monthly over an 18 month period with my endo, who again requested antibody test. My latest results as follows,

Free Thyroxine (T4) 22.9 pmol/L (10.8-25.5)

Free Tri-iodthyroxine (T3) 6.9 pmol/L (3.1-6.8) High

Tsh <0.02 mlU/L (0.27-4.2) Low

Thyroid Peroxidase Antibody >600 (>50kU/L) Positive

Tsh Receptor Antibody 1.16 (0.00-0.39 U/L) High

My diagnosis is - Previous Hashimoto's hypothyroidism with spontaneous conversion to sub-clinical hyperthyroidism, now showing mildly positive Graves' antibodies.

Currently on no meds for thyroid and will continue to be monitored. I feel extremely well and have maintained the lifestyle changes.

My question to the members, has anyone experienced conversion from Hashi to Graves and if so what were your outcomes and timelines. I understand from reading that I could convert to frank Graves, become euthyroid or return to hypo (which given my labs and scan I suspect).

Thanks in advance!

[PurpleNails Administrator]

I suspect eventually you may return to being hypothyroid.

You have 2 autoimmune issues occurring here. With Hashis the immune system attacks your thyroid causing damage, now initially that can cause a temporary rise but you had sufficient damage you needed hormone replacement.

The TPO are clearing up the debris left by the damaged so that how we can conclude you have hashis.

With Graves the thyroid is being stimulated, had you had a fully working / healthy thyroid there’s a strong chance the levels would reach dangerously high levels, but as your working with a damaged thyroid the levels so far haven’t risen very high.

They might go higher & if they become continuously high your would need antithyroid medication. If it holds within range you might not need to start medication at all.

Graves has good chance of going into remission, generally 18 months & doctors look to definitively treat it but many go longer and have excellent prospect of remission. Time lines are not something anyone can predict.

Once your thyroid isn’t being over stimulated then it likely it will return to pre graves state ( ie hypothyroidism)

You may feel very well (possible even better than being on levo) with fractionally high FT3. The issue you may find long term is the down regulation of your TSH.

As someone your had elevated FT3 untreated for a long time (abnormal results were missed by doctors) my TSH never rose again.

This becomes an issue as doctors treat by TSH and yours isn’t going to be reliable & you need to be treated by FT4 & FT3 levels.

[Doodi1 in reply to PurpleNails]

Thanks for your response. So far I have always had FT4 and FT3 checked alongside TSH with my endo. Agree with the concerns of long term suppressed TSH. I have had 2 satisfactory Dexa scans for bone density as there is a history of Osteoporosis in my family.

[HealthStarDust]

Are you perchance on any antidepressant or other medication that can mess with thyroid?

[Doodi1 in reply to HealthStarDust]

No to antidepressants. The only other prescribed meds is HRT, oestrogen patch and oral progesterone.

[HealthStarDust in reply to Doodi1]

That’s interesting as the other hormones do have an impact on the thyroid. I don’t know much about it but I ref it often in the forum.