B12 Serum Tests

[Sasla]

I've had 5 negative B12 serum blood tests, all negative over several years when I suffered and continue to suffer the symptoms of PAS. I am aware of these serum tests being unreliable, & persistent symptoms should be doubled checked with the modern Schilling test or Methylmalonic Acid or MMA Test. Anyone had similar diagnostic problems here in UK I began sub lingual B12 sprays and symptoms improved drastically. Was therefore surprised when GP took another serum B12 test, knowing I was supplementing with B12 spray.

[clivealive Forum Support]

Hi Sasla have you been tested for Intrinsic Factor Antibodies (I.F.A.)?

The fact that your symptoms improved using the B12 spray would indicate that some of it is getting into the cells and starting to repair the damage done to your nerves caused by the deficiency. Therefore don't be surprised if the latest test comes back high.

What treatment were you given for the "5 negative B12 serum blood tests"? I assume you mean that the results were below the bottom of the range as I'm not sure what you are saying.

Was your Folate level tested?

I am not a medically trained person but I've had Pernicious Anaemia (one of many causes of B12 deficiency) for more than 46 years.

I wish you well.

[Sasla in reply to clivealive]

Thank you so much for your helpful reply Clive. Fact is I've had symptoms of PA for many years, but the GP said the serum tests showed, I wasn't 'anaemic' b/c my haemaglobin was fine. Intrinsic Factor has not been mentioned or tested yet. Next GP appt 26/01/19 will hopefully clarify position. I'll mention the Folate & IFA tests & ask if there's been downward trend with my B12 serum tests. I'm rather concerned, that despite the permanent damaged that can occur, the tests for PA seem so 'hit and miss'.

In my case, the cause of my peripheral neuropathy, which prevents me walking for longer than few minutes before foot pain takes over from numbness, was thought to be my spinal-arthritis, 3 herniated lumbar discs & scoliosis which traps spinal cord & nerves.

However since taking the B12 supplements, since 3rd Nov 2018, I can now walk further in less pain, & less numbness. I told my Gp my symptoms had greatly improved, since B12 sprays, so I hope the last set of tests clarify what's happening, b/c it seems too much of a coincidence that things have improved dramatically since starting B12 sprays. Indeed, I understand B12 deficiency can actually cause spinal deterioration!

I'll post my next lot of test results & get back to you. Thanks again for your help, Clive.

Best regards

Sasla

[clivealive Forum Support in reply to Sasla]

I could well have been one of the last in my area to have a "Schilling" test - in fact I had two - one in 1968 which was "inconclusive" (although I was never told why) and the second in 1972 which proved positive for P.A.

It was not a pleasant experience. I was given a huge shot of Vitamin B12 and then had to drink a glassful of water with radioactive B12 in it and given a huge sterilized container in which I had to collect every single drop of urine over a period of (I think) 48 hours and cart that back to the hospital strapped to the back of my motorbike.

I believe the Schilling test was more accurate than the current I.F.A. test but ceased to be used because of the difficulty in getting hold of the radioactive isotopes used in the test.

My then young wife (of three years) in 1968 said she thought I glowed in the night whilst I was taking the test - but that's a different story

[Gambit62 Administrator]

interpreting serum B12, if that is the test you have had, is extremely difficult. It has a very large range which is where most people are okay but it is still possible for an individual to be deficient within that range - just because we aren't averages.

If you had serum tests and they showed a downward trend that would be a good indicator that you have an absorption problem.

Serum B12 isn't the most accurate test - measuring the same sample several times would produce results that vary by 20%- meaning that the same sample could give a result just inside the normal range when others results are below.

There isn't a modern equivalent of the schilling test which was actually a test to look at a number of different potential absorption problems to find out which one was actually going on. The current test for PA as a specific cause, is, as clivealive says, IFA but this isn't a very sensitive test so gives false negatives 40-60% of the time - though it is very specific meaning that it rarely gives false positives.

The problem is that you have to be a bit of a geek to know all these facts about tests and most GPs aren't geeks - they have a poor understanding of the limitations of the tests, of statistics and mistakenly think that the tests tell them all they need to know, rather than being aware that they are guides that can help to point them in the right direction.

If the spray is helping then suggest you stick with it.

[Sasla in reply to Gambit62]

Thank you so much for your speedy reply Gambit62. The info you provided is very helpful, as I'll now be able to have a more meaningful consultation with my GP on 26/91/2019, after which I'll post the findings of the last set of tests taken. It'll be interesting to see if Folate & IFA tests were requested by GP in view of the dramatic improvements since commencing B12 sprays from 03/11/2918. Thank you once again for the advice & being there.

Best regards

Sasla