Discrepancy in test results on same dose - Thyroid UK

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Discrepancy in test results on same dose

Smorzando profile image
20 Replies

I’ve recently had two blood tests - one at the GP surgery, and one at home fingerprick test with Monitor My Health. They’ve come back with quite different results (for FT4, at least) despite being on the same dose, tests done at the same time of day under the same conditions (24 hrs after levo, T3 dose split the day before with last dose 10 hrs pre test).

9th June, GP:

TSH 0.05

FT4 13.1 (9-21) 34%

FT3 not tested

5th July, MMH

TSH 0.05

FT4 18.1 (12-22) 61%

FT3 5.8 (3.1-6.8) 72.97%

My dose is currently 75mcg levo 5 days a week, 100mcg 2 days a week (daily average 82mcg), plus 15mcg Lio (split into two doses, 10 in the morning, 5 at night).

Prior to this dose I was taking 82mcg Levo and 10mcg of Lio, test results on this dose (26th April) were:

TSH 0.36

FT4 16.7 (12-22) 47%

FT3 4.6 (3.1-6.8) 40%

I don’t really feel like my symptoms are improving all that much - perhaps slightly better since increasing my T3, but not much. I am so overwhelmingly tired a lot of the time that daily tasks feel like a massive struggle. My ferritin has a tendency to be low but when last tested was 59 so definitely improving and I continue to supplement with iron.

If anyone has any suggestions they would be very welcome; I am minded to increase my levo by 25mcg a week but to be honest I’m starting to strongly suspect that a lot of my problems are due to perimenopause (I’m 48) and I am wondering if I should explore HRT - I think my hesitancy is largely due to the daunting prospect of yet more hormones to try and balance, not to mention wrestling with the GP (!)

I know  Jaydee1507 posted on a similar subject recently and have found the discussion very interesting.

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Smorzando
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20 Replies
SeasideSusie profile image
SeasideSusieRemembering

Smorzando

A couple of thoughts about the difference in your results.

1) Presumably no change in brand of meds?

2) You have Hashimoto's and fluctuations in results are to be expected, and you are comparing results from tests done a month apart. It would be more of a concern if you were comparing NHS and MMH tests carried out on the same day.

This iron panel done in May is poor:

Ferritin 48.9 (13-150)

Transferrin saturation 23.7 (20-50)

TIBC 53 (45-81)

UIBC 40.4 (24.2-70.1)

Iron 12.6 (5.8-34.5)

Optimal iron panel levels according to rt3-adrenals.org/Iron_test_... are:

Serum iron: 55 to 70% of the range, higher end for men - yours is 23.69%

Saturation: optimal is 35 to 45%, higher end for men - yours is 23.7%

Total Iron Binding Capacity (TIBC) or Transferrin: Low in range indicates lack of capacity for additional iron, High in range indicates body's need for supplemental iron - yours is 22.22% so although your serum iron and saturation show the need to supplement iron your TIBC does not, but we often see this conflicting scenario

Ferritin: some experts say the optimal level for thyroid function is 90-110ug/L

What/how much iron supplements are you taking? Is it prescribed or are you self supplementing? Are you keeping an eye on full iron panel or just ferritin?

Smorzando profile image
Smorzando in reply to SeasideSusie

Thanks for your reply :)

No change in brand of meds, no. Yes, I have Hashimoto’s and I have had up and down results over the years which makes settling on a dose very difficult.

I agree iron/ferritin is low but I am not sure it’s 100% responsible for my symptoms (mainly being utterly exhausted a lot of the time, although it does fluctuate). I am taking 2 x ferrous sulphate a day, not prescribed, and as you saw I had an iron panel done recently, which I shall be repeating. The level of 59 was from the tests my GP did on 9th June. Ferritin was 33 back in February so the ferrous sulphate is obviously working, albeit slowly.

Do you think it is worth a slight increase in Levo (say, 12.5 or 25mcg per week), or should I be looking into HRT, or just persist with the iron in the hope that it might help? Or all three (!?)

SeasideSusie profile image
SeasideSusieRemembering in reply to Smorzando

Smorzando

Don't compare ferritin results from GP with the Medichecks iron panel, it just doesn't work. There have been past posts where there has been disparity with ferritin results when comparing them and it was taken up by one member with Medichecks, you can read about it here (check any links within the posts):

healthunlocked.com/thyroidu...

So it would be best to just stick to Medichecks when checking iron/ferritin status.

I really can't comment on HRT, it's not something I used so have no experience to draw on.

Your MMH thyroid results look pretty good for someone on combo meds. However, it is so difficult to say what's right for someone else. I'm on combo meds and need both FT4 and FT3 reasonably well balanced over half way through range, your results would be pretty good for me but many people on combo meds are fine with a low in range FT4 as long as FT3 is in the upper part of it's range. It really is a matter of gradual tweaking and fine tuning of each individual hormone to find one's sweet spot, and I realise that Hashi's can make this very difficult. If it's any help one would expect to see a higher FT3 than FT4 on combo meds but it's all very individual.

Smorzando profile image
Smorzando in reply to SeasideSusie

Thank you. I read that link (and the links within it) re the difficulty in reliable/accurate/consistent ferritin tests. Quite eye-opening, and alarming! I shall bear this in mind when next testing. I think, though, that given I don’t experience any improvement in exhaustion when supplementing with iron (and I have been on a fairly high dose since early Spring) then it is probably not the biggest factor.

Perhaps I should stick with my current T4/T3 dose for now and see where I am in another couple of months?

JenniferW profile image
JenniferW

My personal experience was that the menopause made my thyroid levels much more unstable. I can't wait for it to be over.

HRT helped with the menopause, but I needed to adjust my thyroid levels after the initial dose of HRT and then again after an increase. I supplement with Vit D and iron and have recently started taking magnesium glycinate, which is certainly helping with my anxiety, as does the HRT.

HRT helped me, but it doesn't stop your levels of oestrogen etc swinging around and therefore your thyroid hormones move around too, i.e. HRT is not a magic fix.

Smorzando profile image
Smorzando in reply to JenniferW

Thank you, that’s interesting and helpful. So, fluctuating estrogen levels cause fluctuating thyroid levels? Could that explain why my levels have been so variable, even on the same dose? (This isn’t the first time I’ve had this sort of large discrepancy).

Did you need to increase or decrease your thyroid meds after you settled on an HRT dose?

JenniferW profile image
JenniferW in reply to Smorzando

After I had started the menopause I got a phone call after a blood test from the doctor saying I was over medicated and needed to reduce the dose slightly, that confused me, as I wasn't expecting my thyroid problem to 'get better'. (It's Hashis). I didn't realise then that it was the menopause.

After I started HRT I had to increase my levo dose a bit and then again after the increase in HRT. I can't remember if I am back where I started before the menopause, but it certainly isn't far off :) It wasn't a big change in dose.

AS14 profile image
AS14

T3 needs serum iron to be optimal to work, its not just about ferritin.

If when taking T3 and you dont feel better or have a bad reaction, palpitations, anxiety, feeling shaky etc low serum iron or low cortisol are frequently the reason.

Your serum iron is much too low. You also need good cortisol.

This information can be found in Paul Robinsons book Recovery with T3, excellent book if youre struggling with T3, everything you need to know with the detail and good solid science behind it.

It can also be found on Stop the Thyroid Madness,they talk about the need for good serum iron and cortisol although their reasons why are in my opinion are flawed but regardless T3 doesnt work if these aren’t right

Optimal nutrients are crucial for good thyroid health, don’t under estimate just how much so. You can waste a lot of time and it can be very confusing missing these.

I cant comment on the discrepancy in the tests, but yes estrogen can affect thyroid levels. If you have too much estrogen ( estrogen dominace as I believe its called) can affect thyroid so can the wrong type or amount of hrt.

For systemic hrt patches should be used instead of tablets, and local estrogen, vagifem pessaries etc are fine but shouldn’t be used every day past the initial loading dose.

I dont understand all the science behind it, far more knowledgeable people on here could explain but I do know its true its happened to me twice.

As Seaside Susie said you need the full iron panel and Id recommend the saliva cortisol test. My preference is medichecks.

Smorzando profile image
Smorzando in reply to AS14

Thank you. To be honest I think I feel a bit more overwhelmed now, there is just so much to consider and to try and find a balance in it all feels like herding cats. I am very very tired and my brain isn’t firing on all cylinders.

I shall certainly take on board your advice about iron and other nutrients although with the doubts about the testing labs it is all rather confusing!

AS14 profile image
AS14 in reply to Smorzando

Youre welcome and yes it does feel over whelming to start with.

I wasted ages wondering why I couldnt get T3/ndt to work. I was so upset when it didn’t work, I knew I needed it but it was either making me more ill taking it or I didnt feel any better. Id have great looking FT3 levels but felt dreadful, couldnt understand it.

Long story how I figured it out, but after a combination of bad advice from an endo and not testing the full iron panel it delayed me for a very long time and left me very confused and down.

I knew I was missing something so I went looking and found Paul Robinsons books, website and fb page and read pretty much everything I could find in relation to T3/ndt .

Thanks to this I managed to fix my low cortisol very easily and I found the information on serum iron. Serum iron is rarely mentioned and had I not read the book I dont think Id if realised just how important it is.

I should point out Im not well at the moment, an unrelated health issue came up and derailed thyroid health but Im almost back to where I need to be to get back on track.

However for a while last year once I finally got serum iron high enough I started to feel better, I couldnt believe it to start with just felt symptoms start to ease , I literally felt like I was starting to wake up and come back to life for the first time in a very long time.

Now Ive felt the start of much better health I know I can start again sorting thyroid. Had I not read that book I honestly dont think Id figured out just how important serum iron is, theres a whole chapter on every nutrient needed and why each is important for thyroid.

Dont expect a doctor to figure this out , read and learn as much you can yourself and test everything advised. Im sure you’ll figure it out

The testing labs can be confusing in the end I stuck with one lab and kept did every test in exactly the same conditions. Its not perfect but I find it helps. My preference is medichecks for all tests.

Smorzando profile image
Smorzando in reply to AS14

Thank you very much for your advice and I am very glad to hear that you are getting back on track with your health 😊

Jaydee1507 profile image
Jaydee1507Administrator

It's confusing and bewildering for sure. There is a whole month though between the 2 tests so plenty of scope for change.

How long had you been on the same dose for each test?

How long have you been on Levo only before adding T3?

I think this is important as if you have been undiagnosed for a lengthy amount of time, then get just Levo which doesn't work and heal then by the time you get T3 added there is much healing to be done.

This is certainly the case for myself. Probably 30+ years of tissue healing plus I have a connective tissue disorder which will likely make healing slower. Do give yourself plenty of time and don't expect overnight miracles!

Like me you are thinking of exploring HRT. As you have read from my thread people do recommend doing that regardless of messing up thyroid levels. I know this is daunting, I am too but I'm hoping it will be worth it.

Personally I have lost a lot of physical strength and am also working (very slowly) to regain that with pilates. It's not just a question of getting hormones right.

Smorzando profile image
Smorzando in reply to Jaydee1507

Thank you :)

I’d been on that dose for around 6 weeks at the first test and 10 weeks at the second test.

I was on Levo only for around 10 months prior to adding T3; I do have the DIO2 polymorphism and despite dose increases my FT3 wasn’t increasing at all (in fact it was decreasing!)

Probably had been hypo for many, many years prior to diagnosis, for example TSH tested back in 2012 was 3.5 but didn’t start levo until early 2020 when TSH reached 11.

Good advice re giving it plenty of time, thank you, and like you I have also lost a lot of strength and stamina which is so frustrating as I lost so many years of my life due to severe mental health issues (2012-2017 especially).

Jaydee1507 profile image
Jaydee1507Administrator in reply to Smorzando

Much sympathy about the mental health issues and losing many years of your life. If only doctors could think outside the box!

I know when I tested too early at just 4 weeks after starting T3 my results were higher than when I retested 4 weeks later. This is months on from that and FT3 has risen back beyond where its been before. Healing really isn't in a straight line and you can only go on your latest results.

What vitamin supplements are you taking? These are also important to keep on top of.

Do try and make a gentle beginning to recovering strength in whatever way might suit you.

Smorzando profile image
Smorzando in reply to Jaydee1507

Thank you. It certainly is a marathon rather than a sprint!

I’m taking ferrous sulphate, B complex (the Pink Tribe liposomal one), 3000IU Vit D; magnesium citrate occasionally. Probably need to be more consistent with that one. I have never felt any benefit from any of these supplements that I could put my finger on but I persist as everyone says how important it is to keep levels good.

Jaydee1507 profile image
Jaydee1507Administrator in reply to Smorzando

Like you supplements appear to have made little difference although when I went up in dose of methylfolate I did feel a bit different. Thats the only one I did particularly notice but I do have the MTHFR variant.

These things are cumulative though and I think some of us more than others need to be extremely patient and just keep up the good work with faith that things will get better in time.

Insomania profile image
Insomania

FYI I had a false high ferritin result recently by medichecks inuvi lab.

I have iron deficiency anaemia, I have nhs iron infusions when my ferritin gets low and I’m (proudly!) maintaining iron now. I have quarterly iron panel by nhs. In between I got a medichecks full thyroid panel which included ferritin.

ferritin results

29th March NHS 183ug/L (10-291)

21st April Medichecks inuvi lab 239ug/L (30-150)

3rd July NHS 133ug/L (10-291)

Even if the range is incorrect, the number is also way off. As can see my ferritin NHS has actually gone down.

I’m now using TDL to test full thyroid panel.

helvella profile image
helvellaAdministratorThyroid UK in reply to Insomania

I suggest you consider contacting UKAS who are in charge of accrediting labs (and many other services). Note that they include complaints AND feedback. Your concern about the test could easily be regarded as feedback if you don't feel a formal complaint is required.

I have a complaint or wish to give feedback about UKAS or one of UKAS’ accredited organisations 01784 429015 customerfeedback@ukas.com

ukas.com/about-us/contact-us/

The registration for inuvi is here:

ukas.com/wp-content/uploads...

Insomania profile image
Insomania in reply to helvella

I did not complain or feedback to medichecks, is that necessary before contacting ukas?

helvella profile image
helvellaAdministratorThyroid UK in reply to Insomania

I'm sorry - I'm not sure - I have not read through the details.

I'd have thought it unlikely to be essential as that could present a barrier to reporting.

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