B12 Deficiency - GP Only Carrying Out Total Serum Test

[RH27]

Hi I posted on the Thyroid forum to interpret my Medichecks result & thanks to this helpful website I was advised my Active B12 levels were low (57).

My Vitamin D levels were also low and my CRP high (10.06) so I consulted my GP who agreed to carry out more bloods. My bloods were taken a few months ago at my Dr's but came back "normal" & I didn't ask to see them.

I showed my Dr the Viapath article about testing for Active B12 as oppose to total serum test and he still refuses to do the Active test. He said if I am deficient it will still show in the total. To me this makes no sense but he hasn't took it on board and worried that my results will come back higher since it will be the total B12.

Does anyone have any advice on how I can approach this?

Many thanks

[Foggyme Administrator]

Hi RH27.

I've had a look at your Active B12 Results (posted in the thyroid forum), which are as follows: 57pmol/L (reference range 37.5-188) so, your Active B12 levels are within normal limits, are reported as normal, and are not flagged as being in the 'intermediate' (low needing possible further investigation) by Medichecks.

I think ThyroidUK told you that these results were low because the information to deduce this was taken from an entirely different lab's website (Viapath). It's not,possible to use the reference range from one lab to interpret blood tests done by another lab (they use different machines so the calibration is different and they may also use different units of measurement).

So...where to go from here...

1) Very few doctors offer the active B12 blood test so...go for the serum B12 and wait to see what the results are. With an Active B12 test within normal limits (as yours is) your serum B12 levels will likely be within normal range.

2) An MMA test could provide clarification about B12 status - but only if you have not taken any B12 supplements (even oral ones). If you have B12 deficeny, MMA will be raised. Very few GP's offer this test - in all likelihood you would have to get this done privately (it's quite expensive).

There is no gold standard test for either vitamin B12 deficiency or Pernicious Anaemia so it's important to note what symtpoms you have - and there are many cross-over symptoms between B12 deficiency and other medical conditions.

I note that Thyroid was reported as normal by ThyroidUK but your blood tests show that you have a vitamin D deficiency. You may find that your symptoms are due to the vitamin D deficiency, so these may well resolve once that deficiency is sufficiently addressed.

Also - your have a raised CRP - this is an inflammatory marker and indicates inflammatory process taking place somewhere in the body. May be due to infection...or could be due to underlying medical condition. Your GP may like to repeat this and then investigate further if it is still raised.

Note: the thyroid forum talk of 'optimal' levels for quite a range of vitamins and minerals - however, these 'optimum' ranges are perhaps relevant to those with thyroid conditions to aid thyroid function. They do not pertain to individuals with no thyroid issues, nor to the supplementing 'well' population , or indeed to those with B12 deficiency - excepting that supplementation is required according to relevant guidance and dosage requirements, where a proven deficiency exists 😉😀.

Think if this was me, I'd get GP to prescribe supplements for the vitamin D deficiency, have the serum B12 test (which will likely be normal), then return to possible B12 issues if supplementing vitamin D doesn't 'fix' you 😉😀. (i.e. perhaps consider MMA test).

It's important that you do not take any vitamin B12 supplements - oral or otherwise) until all vitamin B and/or MMA tests have been completed - it will skew results and you will not be able to determine if originally had a deficiency.

It is possible to have a vitamin B12 deficiency if serum B12 is within normal limits but perhaps not likely, given your Active B12 levels. But this you can post for advice about this if things don't resolve and you want to investigate further.

Good luck and post again if you have more questions about PA or B12 deficiency. 👍

[RH27 in reply to Foggyme]

Thank you for the advice and replying Foggyme. Feel even more confused now as I've had conflicting info on this site regarding the B12 results.

I understand different labs have varying ranges, hence the confusion about "normal ranges".

My symptoms included a wet sensation on the outside of my cheek, muscles twitching every day, forgetting everything, tinnitus etc. so put it down to the B12 as oppose to the Vitamin D. I'll see what happens with my GP when the bloods come back.

[Foggyme Administrator in reply to RH27]

RH37. This site - HU - has many different fora - and each has it's own speciality.

ThyroidUK - where you got your original advice about your B12 results, deals with thyroid issues . And I’ve outlined why their advice about B12 result, in your case, was inaccurate.

This PAS forum deals specifically with B12 deficiency and PA.

So...it’s not the case that you have conflicting advice from this site. You have asked the same question on two different fora one that deals specifically with B12 deficiency, and one that doesn't - hence the different answers.

Bit like asking a heating engineer to fix your car (for want of a another way to put it 😉😀). Both have expertise, just in different areas.

As above, get an MNA test to clarify B12 status if in doubt - or if the serum B12 test is indeterminate and your GP is not helpful.

Good luck with your GP and please remember that symptoms of B12 deficiency have many cross-over symptoms with other medical conditions.

Post here again if you want more advice about B12 deficiency 😉😀

[helvella in reply to Foggyme]

Which is why I so often redirect B12 questions from Thyroid UK to this forum.

[Foggyme Administrator in reply to helvella]

And we thank you for that helvella . As you know, I am a thyroid dunce so likewise, we to you 😉🙃🙃