"Time to abandon the serum cobalamin level for diagnosing vitamin B12 deficiency"

This is an article from the journal of the American Society Of Haematology. Hope the link works as I went to it from a facebook link from Sally Pacholek: bloodjournal.org/content/12...

Quote: "The mass of accumulated data shows that serum cobalamin is an insensitive assay for B12 deficiency and should be abandoned."

They say that if this test was the only test relied on for diagnosis that patients "would" go untreated. I think this should say patients DO go untreated. They recommend the MMA test instead.

15 Replies

  • did you see the presentations at the PAS conference. This one by Dr Dominic Harrington was particularly pertinent.


    Note: think you will need to be logged in as a member on the PAS website for this to actually work

  • No, I would have liked to but I wasn't able to get to the conference and haven't actually joined the PAS - left it too late before the price increase - I have very little income and limited ability to travel due to years of struggling with the symptoms we all know and love (to hate)!

  • Hi Frodo respectfully, the cost of joining PASoc is the same as before - £20.00 only now it is for a one year membership which can be renewed annually should it be needed.

    I would willingly send you £20 if you PM me your address

  • That's really very kind of you, clivealive, but not necessary. I know it is still £20 - and I understand why payment is needed to keep PASoc going - it's the repeated annual payment that's a bit of an issue - once I'd joined I'm sure I wouldn't want to leave after a year.

  • Join now and come back to me in a year - if I'm still "clivealive"

    At least you'll have the benefit of twelve months membership.

  • What a lovely offer.

    I'm sure you'll still be going strong in a year, Clive :)

  • he talked about using 4 tests measuring markers of B12 deficiency - serum B12, active B12, MMA and homocysteine.

    he also made the point that reference ranges are set in a way that is trying to get a reasonable balance between identifying people who aren't deficient as deficient versus missing people who are deficient. the current serum B12 levels on serum B12 tend to miss 25%+ of people who are deficient, and will pick up 10-5% of people who aren't actually deficient as being deficient ... which all rather emphasises the importance of using symptoms.

    Serum B12 is a little more accurate but still has the same problems

    Basically its back to there not being a specific marker that definitively defines a deficiency - but a number of markers that need interpretation in context (ie the symptoms).

    Shame that GPs continue to think that interpretation is just about figures in test results.

  • Thanks.

    Re figures in test results - yes, absolutely.

    And the more legitimate sources that are available the better to make the case when someone highly symptomatic is dismissed as "normal" according to test results and refused treatment. The next hurdle being the individual treatment frequency requirements.

  • Have posted a link to this thread over on Thyroid UK. :-)

  • As I've said before, my personal view is that none of the tests; serum B12, MMA, Homocysteine and active B12 are infallible.

  • What about a combination of them? If serum and active b12 are both low and mma is high then that must be a pretty good indicator - yes?

  • I think a combination of tests is a good idea, Eaoz.

    Despite being highly symptomatic for B12 deficiency for many years, the majority of my tests have come back normal range/negative.

    When I started to self treat, some of my symptoms disappeared, some improved, some stayed the same.

    I feel that where a person is symptomatic for B12 deficiency and has had other possible conditions ruled out, consideration should be given to a trial of B12 injections even when MMA, Homocysteine, Active B12, serum B12 do not indicate an obvious problem.

    I think that there are relevant cases in the book "Could It Be B12" by Sally pacholok and JJ. Stuart.

    My feeling is that eventually other causes of B12 deficiency with be found besides those known about today, perhaps with advances in studying genes involved with B12 metabolism, folate metabolism, intrinsic factor production etc.

  • I agree, I don't believe any medical test is infallible either, Sleepybunny, the best they can be is an indicator, along with symptoms, as Eaoz says. The more informed we are about the tests used to give or deny diagnosis and treatment the better, as we are all aware now that "normal" results can be fairly meaningless.

  • My other half developed neuropathy. He also had restless legs and was referred to a Neurologist. Because he had high insteps and funny shaped toes he dx Charcot Marie Tooth Disease. He was also given Dopamine for the restless legs which was gradually increased with not a lot of improvement but worsening symptoms of periodic limp movements. He was then referred to the countries leading CMT specialist in London who ran nerve conduction tests etc. A year later he had a follow up with her and after more tests they decided he didn't actually have CMT but idiopathic neuropathy. Some months later I attended the Thyroid Conference and the PA lecture and nearly fell off my chair when I heard the list of symptoms for PA. I spoke to the lecturer afterwards who asked if he had ever been tested for B12 deficiency and of course he had not.

    The next day I called my GP and asked if I could start giving him B12 injections as a trial for his neuropathy and gave the reasons why along with studies I had found. She agreed as I could give them as I was doing mine anyway. I told her that if they worked she could stop prescribing the Dopamine which was more expensive than the B12!

    Now, a year later his RL and PLM are practically gone, just the odd night he will have a twinge. His neuropathy unfortunately has not improved so I suppose thats permeant damage.

    His B12 was around 250 but they don't re-test because he's now being regularly injected. Id like to know what could have caused this in the first place and why no one thought of it as a cause for the neuropathy before I did?!!

  • Yet another terrible, terrible story of misdiagnosis, fortunately with a fairly good outcome - but only because you were proactive and were forced to take matters into your own hands

    Why nobody thought of PA/B12 deficiency as a cause - with all the information that is freely available and the fact that Pernicious Anaemia and its symptoms have been known to the medical profession for a very long time - is a question we would all like to see answered.

    The unnecessary suffering caused by misdiagnosis is catastrophic. I should think only a small fraction of PA sufferers find their way to this forum, so presumably all those we do hear about are the tip of the iceberg.

    It's especially insane that dogs can be given weekly injections of B12 for long periods whereas people struggle to get diagnosis and treatment (no offence to dog lovers). Should we be getting appointments with the vet instead?

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