How do I know.....

[Lilnicki]

If I have functional B12 deficiency rather than Pernicious anaemia...... Would symptoms be different ? .....or would blood test results be different ??

[Poppet11]

Short questions requiring unbelievably long answers.

The problems associated with identifying and testing for b12 deficiency seem to grow by the minute - the whole situation now would be funny if it wasn't so serious.

Okay, let's try a breakdown.

Pernicious anaemia - one cause of b12 deficiency. The diagnostic criteria appears to vary. It used to be a lack of intrinsic factor but now they are looking for intrinsic factor antibodies.

It was considered that pernicious anaemia was what happened when b12 deficiency became 'more serious.' Yet the phrase pernicious anaemia is very old and the diagnostic criteria has changed over the years, as has the knowledge of how the illness really progresses.

So, if you stick with the fact that pernicious anaemia means that the patient has a b12 deficiency caused by intrinsic factor antibodies (these antibodies simply prevent the individual absorbing b12 to one level or another) then you've got it about right.

To get a diagnosis of perncious anaemia, you need to test positive for instrinsic factor antibodies or parietal cell antibodies - whatever. These tests are notoriously unreliable.

People who don't test positive have a b12 deficiency of unknown cause (in most cases unless they have dietry restrictions) They eat well, so it's nothing to do with diet - it is the body malabsorbing b12 for another 'unknown' reason.

So, both categories are of a b12 deficiency. The damage the lack of b12 causes is, of course, the same. Which is why the light is finally dawning and the professionals are advising to throw the tests in the bin and treat the symptoms. Alright not quite in the bin. But most of the tests are worth diddly squat.

And then, even if you get it identified, because they still think they are dealing with anaemia (which they aren't) the doctors are quite happy to consider you treated when your b12 levels move into the normal range.

It's such a mess it makes your head spin!

[Lilnicki in reply to Poppet11]

Thank you.... That helps a lot

So if my FBC and serum B 12 are normal, and my intrinsic factor and parietal come back normal....., I could still technically have B12 d ?

So the tests I would then need are active B12 and MMA ?....... Think if they refuse to do those I will get done privately !

The neuro symptoms are still playing on my mind !

[Poppet11 in reply to Lilnicki]

Yes. The tests on the FBC are subject to interference - MCV to folate etc. The serum b12 test is not only set too low to identify neuro damage, but is affected if the patient is stressed and only measures the total amount of b12 in the blood - since only a proportion of that can be utilised by the body you can see how that can be affected. Parietal cell tests can be affected by other conditions, IFA test is very specific but bordering on useless. It is only about 45% accurate and it can be severely affected if the patient has had b12 in the recent past. It literally will throw up the opposite result. So if you have b12 on a Monday and have an IFA test on a Wednesday and you have got IFAs it will throw out that you tested negative for IFAs.

The active b12 again is not 100% reliable - there are no case studies available for the research. The MMA is considered possibly the most reliable but this too is not 100% and can be affected if you've recently had b12.

Homocysteine is affected if you had folate.

... and I've just knocked out the simplified version - you can see what a mess it is. How on earth anyone is supposed to get diagnosed before they end up in a wheelchair, I don't know. It's a wonder anyone gets diagnosed at all.

I even find myself feeling a bit sorry for doctors - when they find out all the problems where does that leave them? Oh, I know. Treat the symptoms!

[Gambit62 Administrator]

Simple version: The symptoms of PA are the symptoms of B12 deficiency. PA is not the only cause of B12 deficiency.

To add to complications - even if you have B12 in your system the body still has to convert it to a form that it can use - active B12 test is a bit better than whole serum because it is more specific about the form of B12 that it looks at.

Although people understand the way B12 is used by the body a lot better now than they did there are still a lot of grey areas that aren't really understood around how it is metabolised, particularly at the cellular level and if I have understood what I have read properly it is possible that some people really have problems at this level rather than other levels which, for them means that the whole idea of measuring the B12 they have is a bit of a nonsense.

Part of the reality is that the understanding of what is going on in detail is incomplete ... and the methodology for diagnosis hasn't really caught up with where current understanding is on how B12 works.

[Poppet11 in reply to Gambit62]

Although I don't think it's that one individual would have more problems in the grey area than in the deficient range - but that someone with, for example, a level of 260 might only have 30% active b12 available - so a more accurate figure would be 78. And someone with a level of 180 might be absorbing 50% so they would be around the 90 mark.

But the person who is at 180 would be classed as deficient and the person at 260 wouldn't.

That aside, you're quite right, because it really isn't understood no one understands the anomalies - and there are loads. There always has been. When people used to die of it (and they looked at both the anaemia and the clinicial neuro problems regarding cause of death) a few people were recorded as dying purely of the anaemia. They had no neuro symptoms in life. But when the spinal cords were dissected they were severely damaged!

And the haematologists today are still trying to establish a specific protocol for diagnosing and treating all of us - without communicating with us when we are alive or taking us apart when we are dead. Can't be done.

[Poppet11]

Nice post, Gambit (although I do think I set it up for you...-))

I thought of something else last night.

In most of the world now they rarely use the phrase pernicious anaemia, the term b12 deficiency is used no matter what the causation - Although sometimes people still recognise it as Biermers. They don't appear to focus on the causation - a b12 deficiency is a b12 deficiency. Maybe it is mainly the UK, and possibly the US, which are still hung up on the pernicious anaemia thing?

[Poppet11]

... and something else.

Even if the metabolic pathway was correct in that the anaemia presented first, or that the response time meant someone with cellular problems would reveal anaemia the next day - many of us never reveal the signs of the anaemia haematologically because that too can be affected by the folate and iron issues. And rarely do they test for iron specifically - they test for ferritin if anything (another accute phase reactant which also doesn't reflect iron circulating) and I've never been asked yet if I am taking supplements in the form of folate.

The end result of all this is that it is extremely difficult to get diagnosed for anaemia never mind a b12 deficiency and a diagnosis for PA - which is the only form doctors consider can be serious, is virtually impossible.

Take it from me, you can be very, very sick and half crippled and they will still say you are okay because you haven't tested positive for x, y, and z. And then they will tell you you're fine because your 'b12 levels are normal now!'

[Hidden]

IF antibody test is 100% conclusive for PA, if positive you have IFAbs positive PA, if you test negative then you are classified as IF Abs negative PA. The IF antibody test is notoriously unreliable, people have tested positive then negative etc.

See:

patient.co.uk/doctor/pernic...

"IF antibodies (IFAs), if present, are virtually diagnostic (100% specific) for pernicious anaemia. However IF antibodies have lower sensitivity with studies showing IFAs present in as few as 27% of patients. Therefore the absence of IFAs does not rule out the diagnosis of pernicious anaemia.

Gastric parietal cell antibodies (PCAs) are less specific but more sensitive for pernicious anaemia. Combining IFA's and GCA's increases the sensitivity to 73% while maintaining 100% specificity for pernicious anaemia.2

What ever your test results, your treatment should be the same.

I am (and most of the 7 in my family known to be or were on B12 treatment are) negative for all specific tests for PA, still no doubt we have a problem taking up B12 and am classified as PA (IF negative) and need life long treatment, so do (or did) the others in my family. It is not always known why you are B12 def/ dependent on B12 treatment.

Kind regards,

Marre.