Are blood test very acurate ? I put it to the t... - Thyroid UK

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Are blood test very acurate ? I put it to the test.

Iperry1 profile image
11 Replies

I have had a under active thyroid for 20 years. I take 250mg of thyroixine daily.

The problem I have got is from time to time I go back down hill and find my symptoms re-appear. I aske for another blood test and they allays say its fine.

So frustrated with the answer I decided to try a experiment. I dropped my dose by 50mg per day for 4 months. Then I went back to the doctors for another blood test. Sure enough the reply was the usual ''yes your result are fine"

So then I uped my does back to 250mg per day. Waited 4 months and went back for a blood test. Yes, the result came back normal.

This means a difference of 50mg can't be detected by a blood test or the results are read different every time or none can be arsed.

The doctors told me the levels don't change for 6 weeks however I waited four months and they still could not pick up a different result.

Feels like they are just not interested.

I have just asked for another blood test then will send in the result. Also what is t3's and will they check them with a normal blood test.

Thanks

Ian

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Iperry1
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11 Replies
greygoose profile image
greygoose

Ian, you can't make any assumptions without seeing the blood tests for yourself. One should never, ever take one's doctor's word for anything! It is totally possible that there were huge differences in the results but as each time they were 'in range' the doctor interpreted that as 'fine'. They don't know any better.

Get copies of all your blood tests and have a look for yourself. if you don't understand them, post them here, someone here will be able to help you.

But have you had your antibodies checked? Sounds as if you are having Hashi's swings, and the only cure I know to that is a suppressed TSH. Get your results and see for yourself.

Hugs, Grey

Iperry1 profile image
Iperry1 in reply togreygoose

Thanks for your help.will look into the points you have raised

poing profile image
poing

If you get copies of those results, then I bet that you'll find quite the results of those blood tests are quite different, even though they were within the "normal" range. The normal range is very wide -- too wide.

PR4NOW profile image
PR4NOW

Ian, the blood tests have a low 'index of individuality'. In case you missed it here is a link to a presentation that explains the concept. You need to download both pdf's, the slide notes and the presentation and open them side by side so you can read the notes as you look at the slides.

aacc.org/resourcecenters/ar...

It is not surprising that both tests would be in the 'normal' range. As Grey and poing said you need to get copies of the tests and see what they actually say. T3 is the active thyroid hormone that is used at the nuclear receptors. T4 is the prohormone that needs to be converted to T3. From what has been said on the site getting a T3 or a FT3 test from a doctor can be difficult, also getting a TPO Ab for Hashimotos can be difficult, both can be useful. PR

Jackie profile image
Jackie

Hi They can alter but are normally accurate. However, for anything life threatening or even lots of things. If test bad, then you have a repeat a week later. For thyroid you need a Free T3 test and the other tests as it could well be them, Graves disease, unusual but can cause swings.If you do not feel well now and nothing to account for how you are, then it is time to find a good Endo yourself, then ask GP to refer you.

Best wishes,

Jackie

Not sure if you know, to refer to any post, click on" Reply to this" under that post, or we do not know.

Iperry1 profile image
Iperry1 in reply toJackie

Hi,hanks for your reply.

I am going to,get some new bloods done and try and find a private Endo. Got to be worth putting the bill on a credit card than living with this.

Stourie profile image
Stourie in reply toIperry1

Hi Ian you should still go back to your doctors and get copies of all your blood results.

Jo xx

Jackie profile image
Jackie in reply toIperry1

Hi Good but do careful research to make sure they are good, do not rely on GP. Consultants will write to GP to do all tests and of course they do for drugs etc anyway. So, if you ask the Endo, you will only have to pay for the consultations, unless you choose top pay for the tests etc. Makes no different as they are only paid for the consultations, normal practice, I see This is a consultant so of course they work in the NHS too unless retired, not a private doc.lots.

Best wishes,

Jackie

valerie profile image
valerie

Ask on here for a list of good endocrinologists in your area as so many are bad....Valerie

shaws profile image
shawsAdministrator

louise.warvill@thyroiduk.org has a list of NHS Endos and private doctors if you email her.

I browsed my medical records to find I had a very abnormal TSH and borderline T4 blood test in 2009. It had been starred and highlighted in my records, but I was never told about this until the end of 2010. NEVER EVER let the Drs fob you off. I request a print off of all my bloods now and keep a copy. I also log them all in Excel in graphical format as it depicts the changes a lot better than the Drs 'graph' software which flattens it all really badly so it all looks normal..... And you can plot T4 vs T3 etc.

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