Normal active b12 and serum b12 - does that mean I don't have pernicious aneamia?

[gemini4378]

Hello,

I have recently come across pernicious anemia, I am 34 and have distil myopathy - nerve damage and muscle wasting in my legs (unknown cause) and I also have tinnitus, psoriasis, underactive thyroid and a life long struggle with mood and tiredness. I was excited to find this website as I was hoping it could provide me with some answers but my Serum b12 is 674 ng/L (normal range 180 - 900 ng/L) and my active b12 is 146 pmol/L (normal range being = 25.1 - 165).

My question is, does this conclude that I don't have pernicious anaemia?

I'm tempted to get further tests but they are expensive and don't seem to be very conclusive.

Thank you in advance for your help.

[fbirder]

That's right you don't have PA.

Your B12 levels are way above the average.

[wedgewood in reply to fbirder]

But what are we to understand by the term “ Functional B12 deficiency ? “

[fbirder in reply to wedgewood]

A functional B12 deficiency is totally different from PA.

A functional deficiency means that there isn't really a deficiency in the vitamin under question - there is plenty of it in the body, but it cannot fulfil its function.

The best example of a functional deficiency is that caused by the Folate Trap - b12science.com/B12Science/D... where a real deficiency in B12 results in a functional deficiency in folate.

All the folate in the body gets trapped as methyltetrahydrofolate, because B12 is needed to convert that to tetrahydrofolate. There is lots of folate in the blood, but it's all in an unusable form.

With a functional B12 deficiency there is plenty of B12 in the blood (it is getting absorbed properly, hence no PA). But something is preventing it from doing the jobs it is supposed to be doing in the cell.

The simplest functional deficiency is caused by a mutation in the gene that codes for the transcobalamin protein. Children with two copies of this mutation cannot get enough B12 into their cells. They have all the symptoms of a deficiency. It's a very serious problem and often results in early death in infancy.

There are hundreds of other processes in the body that may not work properly, causing a functional deficiency.

The presence of a functional deficiency can be detected by: some symptoms of a B12 deficiency, the presence of high levels of B12, and high levels of MMA or hCys. Methylmalonic acid and Homocysteine are chemicals used up in the two reactions mediated by B12, If the B12 isn't doing a proper job then one, or both levels of MMA and/or hCys will be increased.

But that's still not going to tell you what the problem is - why the B12 isn't doing its job properly.

[wedgewood in reply to fbirder]

I really appreciate you giving me such a comprehensive answer . It’s helped me enormously as a complete non-scientist to grasp the meaning . Thank you very much .

[Gambit62 Administrator]

The results strongly imply that you don't have B12 deficiency. That doesn't entirely rule out the involvement of B12 but that would be genetic and would be off topic for this forum.PA is an auto-immune disorder that affects absorption of B12, eventually leading to a B12 deficiency. The only real way of being sure that you don't have an absorption problem is to check serum/active b12 levels over time to see if the are dropping

[Foggyme Administrator]

Just a thought gemini4378…

I see you have psoriasis and hypothyroidism (Hashimoto’s). Both of these are autoimmune conditions and autoimmune conditions tend to arrive in 'clusters' - once you have one autoimmune condition, others may arise too (though this is not a given).

It looks like B12 deficiency is unlikely so because of your history of autoimmune conditions, it's worth asking your GP to run blood tests to screen for autoantibodies, just in case another autoimmune condition is evolving.

If any of your autoantibodies are raised, then onward referral to a rheumatologist would be required so that they can undertake more investigations and bloods tests (the tests a GP can do are quite limited in comparison and will not be able to identify any particular condition - just that there may potentially be one and that further investigations are necessary - hence a referral).

Interestingly, at one stage I thought my B12 deficiency was out of control again - may symptoms reoccurred after being well controlled for some time. To cut a long story short, I eventually had autoantibodies screened, was referred to a rheumatologist, and ultimately diagnosed with lupus. I'm certainly not suggesting that this is what you have, just that there are many underlying conditions that can cause symptoms that appear to be identical to those in B12 deficiency, so worth investigating other possibilities. And with a history of autoimmune conditions, then that would be a good place to look - even if only to rule out other autoimmune conditions.

Very best of luck and I hope you find some answers soon x