EH up, never expected that.

[Polo22]

Managed to actually get a GP face to face appointment this morning.

That's a result in itself. So , went ready to argue my case for repeat testing, testing PTH, IF, .

Started discussion by stating I was not criticising the practice, or individual GP's because I understand it is a very specialised topic but.....this is what I want. Showed her results from BlueHorizon, she pointed out B12 result was high, I pointed out it was same range but different units of measurement, and explained how to convert Thanks SeasideSusie. Shocked she listened, expressed some concerns, discussed them , told her I was self injecting, raised eyebrows, but explained the improvements I was experiencing. So came away with barrage of blood forms, PTH, IFA, B12 and Folate, Ferritin, Iron studies, LFT, RP, Vit D, Full Blood Count, HbA1c, Calcium profile, and the infamous TFT3,

So now going to book blood tests , she said she was willing to increase thyroxine but just wanted bloods done first to have baseline.

[Alanna012]

Wow what a great result Polo22. Well done for speaking up for yourself! Amazing that's about a billion tests you got ordered there!

Can I ask about how you convert between the different measurements for B12 please?

You could potentially do this as a job, you know, shadowing thyroid patients as an advocate.....new vocation for you 🙂

Now me, they get defensive straightaway. I do have a bit of a school teachery voice so I don't know if that's what it is..but I never get anywhere, although I've tried. Even me being sickly obsequious doesn't go down well and putting it on doesn't last long in any case....they see through me lol....

[SeasideSusie Remembering in reply to Alanna012]

Alanna012

Because the recommendation for B12 level comes from the book "Could it be B12?" by Sally M. Pacholok:

"We believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".

"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."

then we need to be careful that we are using that unit of measurement when looking at the B12 result.

ng/L is also often used and this is the same as pg/ml so no conversion is required.

Blue Horizon private test and some GP tests use the unit of measurement pmol/L so this needs converting to pg/ml and we do this by multiplying the pmol/L result by 1.355 to give the pg/ml result, eg

450pmol/L x 1.355 = 609.75pg/ml

[Alanna012 in reply to SeasideSusie]

Brilliant thank you SeasideSusie!!

Right so doing this with my last BH result on a calculator I get:

686.985

(507×1.355)

I see I need to retest, as I was just saying on another thread as I supplement with B Complex, but not B12 separately.

[SeasideSusie Remembering in reply to Alanna012]

Yes, that's correct and 686.98 is a pretty good level. You do not need a separate B12 with that level, only if it was quite a bit less than 550pg/ml.

However, Total B12 (which is what BH test) is not the best test as it measures the total amount of B12 that is both bound and free (active) and it's the free/active B12 that is available for the cells to use, so the Active B12 test is the better test and we suggest 100 plus is a good level, anything below 70 would suggest testing for B12 deficiency.

[Alanna012 in reply to SeasideSusie]

Thank you Seaside, honestly you and the other mods and contributers are a blessing on these threads.

I'll carry on doing what I'm doing then, as I think my last active B12 was just above 100... possibly 112 or something in that range. Mind you I might have been supplementing up to a week beforehand.

For future reference when supplementing, how far away should you stop before testing?

[SeasideSusie Remembering in reply to Alanna012]

If you were taking a separate B12 supplement then you'd carry on up to and including the day before the test, then the result is measuring what your supplement is achieving and you'd know if you need to adjust the dose.

With B Complex you need to stop that 3-7 days before any blood test as the biotin it contains can cause false results when biotin is used in the testing procedure, which most labs do use.

If all you are taking is a B Complex then it is maintaining a good B12 level for you.

[Alanna012 in reply to SeasideSusie]

Thanks again!

No I was using a B12 supplement only before, then read you need the other supporting B's so switched to complex.

I will have to retest to see how effective the B complex is.

I didn't realise it would make a difference until now.

[tattybogle]

The difference between the TSH on these two tests is surprising ,... just to clarify .. how long ago was the first one .....and was that when you were on 125mcg ,or was it on 150mcg and this is the test that led to the dose reduction ?

"Eventually agreed to reduction. My last lot of numbers was 0.81 mu/L serum TSH, 22.3 pmol/L serum free T4. .... I currently take 125mcg, test was done about 10 am, I normally take meds about 06.30 maybe 7 am. I usually don't take meds before testing "

recent blue horizon tests:

TSH 8.9 [0.27 - 4.20]

T4 total 106.0 [66 - 181]

Free T4 17.2 [12.0 - 22.0]

Free T3 3.11 [3.1 - 6.8]

[Polo22 in reply to tattybogle]

It was last June (June 21) had been on 125mcg for some time, 1 or 2 years prior on the 150mcg. Maybe I forgot and didn't leave a long enough time between test and last dose, head has been all over for some time. I was meticulous with timings this time , plus GP test no Free T3.

[tattybogle in reply to Polo22]

'time of last dose' won't affect TSH result ..... it only affects fT4 result. so it's not that .

So if both TSH 's are on 125mcg it's even more ???? to get 8.9 now .

[Polo22 in reply to tattybogle]

??? No idea then